Jobs to do in the garden in May

Close up of an early summer border with alliums, poppies, geraniums and cosmos

Image: Canva

The garden is really racing ahead and it’s a job to keep up with it. Getting on with tasks now will enhance your summer displays, but don’t forget to give yourself some time to relax outside and just enjoy it! 

Bedding

Close up of woman putting out pink petunias ready to plant them

Summer bedding is perfect for plugging gaps in borders
Image: Shutterstock

Spring bedding will be fading and it’s time to switch to summer varieties. If you live in cold parts of the UK and you don’t have a greenhouse or cold frame then you will need to resist the temptation to buy these frost-tender plants too early. Tender bedding plants need to be gradually acclimatised to outdoor conditions after purchase, but you can save yourself the hassle with our Garden Ready plants which have already been hardened off for you. Our pre-planted hanging baskets are also great time-savers.

Greenhouse

Greenhouse in a garden with doors and vents open

Open up the doors and vents in your greenhouse as much as possible
Image: Canva

It can get really hot in the greenhouse so ventilate it as much as possible. Invest in a maximum /minimum thermometer and keep an eye on temperatures. Ideally, you don’t want them to climb above 80 °F or 26 °C. When a greenhouse gets too hot plants stop growing, become stressed and succumb to pests and disease. Aphids, whiteflies and red spider mite will quickly take hold and multiple rapidly in these high temperatures.

In an overheated greenhouse small seedlings can be frazzled incredibly quickly. Seedlings which have just been pricked out are especially vulnerable and it’s important to have a cool, shady spot for them somewhere. Cool down your greenhouse and protect your seedlings by painting some greenhouse shading on the glass. I tend to paint shading onto one side of my greenhouse, which I use for seedlings, but leave the other side for my sun-loving succulents. The other way to cool an over-heating greenhouse is by ‘damping down.’ This simply means flooding the floor with water which will cool the greenhouse quickly by evaporation.

Feeding

Close up of person putting granular fertiliser around a young tree

New trees and shrubs will appreciate a spring feed with granular fertiliser
Image: Shutterstock

Container plants

At this time of the year winter rains have washed a lot of nitrogen out of the soil and plants may start to look hungry and exhibit yellow leaves. Specimens which have been permanently growing in containers will have used up all the nutrients in their compost and can struggle to put on new, leafy growth. Top dress them with a balanced fertiliser which includes trace elements such as Vitax Q4.

Bedding

When potting up seasonal containers and hanging baskets, professional gardeners always incorporate slow-release fertilisers into the compost. This saves an enormous amount of time on applying liquid fertilisers. Liquid feeds can be useful as a top up but are more wasteful as much of the feed simply drains out of the pot. They also tend to result in inconsistent feeding, promoting surges of soft, sappy growth. Try using a controlled release product such as Incredibloom instead – it will continue to feed your plants for about 7 months.

Roses

Feed hungry roses with a proprietary rose feed now. These contain high levels of potassium to promote flowering.

Pelargoniums (Geranium)

Pelargoniums will also benefit from a flower-boosting high potash feed. Avoid giving them nitrogenous feeds, which will encourage the production of leaves over flowers and create soft growth which is more vulnerable to fungal diseases.

Plant supports & ties

Close up of lilac delphiniums inside rusted metal plant support ring

Tall plants like Delphiniums are best supported early on
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Herbaceous borders

Plants are growing rapidly and it’s important to get them supported as quickly as you can. If you are like me, you probably tell yourself this every year, promise to do it next weekend, and then, before you know it, the plants have shot up, the first rain storm hits and everything falls over into a mess! It’s a wise idea to purchase some supports early on so you can avoid getting yourself into this pickle.

Climbers

All your other climbers, such as climbing roses and clematis, will need regular tying in. Sweet peas left to trail along the ground not only grow poorly but are targets for slugs and snails so tie them onto their canes or obelisks early on. I prefer natural jute twine as it’s biodegradable and blends in unobtrusively. Tie the twine in a figure of 8 allowing room for the plant stems to expand. I like to put the string around the plant stem first and then wind it around the support twice. That way you can hide your knots on the back of the support and the tie won’t slide up and down.

Watering

Close up of person pouring bucket of water around root ball of newly planted tree

New trees and shrubs should be ‘puddled in’ on planting and watered frequently during dry weather
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Springs have become increasingly dry and the recent weather has been warm but windy. This combination of high aerial temperatures and wind really licks the moisture out of plants and can quickly desiccate them.

Before you plant new plants, soak the root ball by plunging them into a bucket of water. After planting, water them regularly in dry weather. It is best to give plants a generous soak at longer intervals rather than frequent but sparse watering which only encourages surface rooting. Once the root balls of containerised plants have dried out underground they tend to repel water and can remain surprisingly dry after watering attempts, so aim to keep them moist.

Pruning

Close up of gardener sawing off a thick, low stem from a Ribes (flowering currant)

Cut out a proportion of the old stems from early spring flowering shrubs such as this Ribes (flowering currant)
Image: Annelise Brilli

Early spring-flowering shrubs

Prune established spring- flowering shrubs such as forsythia, Ribes (flowering currant), Spiraea ‘Arguta’ (bridal wreath), Exochorda (pearl bush) and Kerria japonica. These shrubs flower on growth produced in the previous year and so they need to pruned immediately after flowering.

You can take out up to one third of the oldest stems, cutting them back to a shoot/bud near the base. Pruning out the oldest stems will encourage the formation of new ones so that the wood is continually renewed. With Kerria japonica you can cut back all the previously flowered stems.

You can also trim back the top of stems to keep them tidy but bear in mind that these shrubs have an arching habit which you don’t want to ruin. Always try to prune them back to a convenient shoot lower down rather than leaving stubs.

Japanese Quince

Chaenomeles (Japanese quince) has a twiggy rather than arching habit. Shorten the new growths to encourage the formation of lots of short, flowering spurs.

Evergreen shrubs

Inspect evergreen shrubs and prune out any frost damage.

Pyracantha

Wall trained pyracanthas can be pruned back now, reducing outward-facing shoots to a few inches and removing completely any shoots growing into the wall. This will inevitably remove some flowers but it will promote the formation of short spurs which will become crowded with future flower buds and berries.

Dahlias, cannas and other tender perennials

Close up of dahlia tuber with lots of soft new shoots

Dahlia tubers should be shooting well by now
Image: Shutterstock

Harden off your tender plants which you have been overwintering in a frost-free place. Plant them out when all danger of frost has passed. This is always a gamble but generally you should be safe by the end of the month.

If you don’t see signs of growth on your tender perennials don’t give up on them too soon -they are slow into growth. All the top growth of tender Salvias may completely die off but don’t throw them away in haste – many varieties will re-sprout from the base.

Chelsea Chop

Crowds at the Chelsea Flower Show which takes place in May

The Chelsea Flower Show is a reminder to do the ‘Chelsea Chop’
Image: Shutterstock

Enjoy the Chelsea Flower Show which runs from 24-28th May this year, and use it as a reminder to try out a pruning technique called ‘The Chelsea Chop’.

If you want to keep your herbaceous perennials shorter, sturdier and more compact, you can chop them back by up to a half in late May or early June. This pruning technique will produce plants with shorter, self-supporting stems and more (but usually smaller) flowers. Not all perennials will respond to this treatment but those which do include: Asters, Echinacea (coneflower), Helianthus x laetiflorus (perennial sunflower), Hylotelephium (Sedum), Monarda (Bergamot), Nepeta (Catmint), phlox and rudbeckia.

Seed sowing

Close up of hand sowing seeds into seed drills in soil

Sow flowering annuals in rows the same way as you would with vegetables
Image: Canva

  • The soil is lovely and warm now and hardy annuals can be sown directly into the ground. Rake the soil well to make a fine tilth and sow them in rows. Sowing in rows makes it much easier to distinguish between your flower seedlings and weed seedlings. Once the seedlings have grown and you have thinned them out, you won’t notice that you originally sowed them in straight lines.
  • Thin out/pot on any annuals sown earlier.
  • It’s a bit late now to sow most tender annuals – best to buy them as ready-grown plugs.

 

Close up of deep red flower of Erysimum 'Scarlet Bedder'

Biennials such as Wallflower ‘Scarlet Bedder’ can be sown this month
Image: Canva

Don’t forget to sow biennials for next years bedding plants. Wallflowers like the sumptuous ‘Scarlet Bedder’ and dainty forget-me-nots will make fabulous partners for next year’s tulips. Pansies sown now will provide vibrant colour in the winter, whilst Bellis perennis ‘Pomponette’ will grace window boxes and border edges with bright pom poms next spring. For cut flowers, you can’t beat clove-scented Sweet Williams (Dianthus barbatus).

Close up of a pale pink foxglove flower spike

Foxgloves are cottage garden staples and great for bees
Image: Canva

If you are looking for some flowers for the wildlife garden, foxgloves will provide plenty of food for foraging bees. They should be sown now on the surface of trays of fine compost or in a patch of spare ground. The tiny seeds are like dust and shouldn’t be covered – they won’t come up if you do! Sweet Rocket (Hesperis matronalis) will also attract pollinating insects with its sweetly fragrant blooms.

Lawns

Close up of a drop spreader on a lawn

A drop spreader is a useful tool for fertilising large lawns
Image: Shutterstock

Fertilise

Apply spring fertiliser to lawns. If you only have a small to medium family lawn ecofective Lawn Feed is an organic treatment which will treat up to 150 square metres and is safe for pets and children.  For large lawns, Sportsmaster Spring & Summer is a high nitrogen, slow-release formula which you can use all growing season.

Try to keep your use of weedkillers to a minimum. Remove deep weeds by hand or spot treat them. If you are going to resort to chemicals, it is much more effective to use a separate fertiliser followed by a weedkiller product, such as Weedol, rather than a combined treatment. Fertilising first boosts the grass in its competition with the weeds, enabling it to quickly grow into gaps after treatment. Meanwhile the weeds will put out more leafy growth, which will absorb more weedkiller.

Mow

Keep mowing your grass every week, gradually reducing the height of cut as the weather gets warmer. Better still – stop mowing and weedkilling altogether! And join in with No Mow May – see below.

Pest control

Close up of a ladybird larva on a stem. The six-legged larva is pale grey with yellow spots.

Avoid using chemical pesticides which are not only harmful to your enemies but also your garden allies such as this aphid-munching ladybird larva
Image: Canva

  • All this warm weather means that pests are rapidly multiplying. Use environmentally friendly sprays such as ecofective Bug & Mildew Control to keep on top of aphids, black fly and red spider mite.
  • Order biological nematodes to control a range of pests which rapidly emerge in spring including slugs and vine weevil.
  • Whitefly in greenhouses can quickly become a real problem, so introduce the parasitic wasp, Encarsia formosa, before pest populations build up.
  • Treat roses with a preventative anti-fungicidal spray before blackspot, rust and mildew take hold.

Clematis

Close up of gardener using plastic coated twine to tie in clematis stems

Keep tying in clematis but use natural twine, which biodegrades, rather than this plastic coated wire.
Image: Shutterstock

  • Regularly tie in clematis to its support.
  • Clematis montana does not need regular pruning but if it’s getting out of hand in a confined space you can trim it back now and remove any dead or diseased growth.

Plant propagation

Close up of persons hand with pair of secateurs cutting a soft stem tip

Softwood cuttings should be about 3-5 inches (7.5-12.5cm) long
Image: Canva

  • Take softwood cuttings from hardy perennials, shrubs and tender perennials such as pelargoniums and osteospermums. Although softwood cuttings should be pliable, the very softest growth will often wilt quickly and is less successful. Wait until the material has firmed up slightly and gives a little snap when you bend it.
  • Once they have finished flowering, cut back and divide spring flowering perennials such as Pulmonaria (lungwort), Doronicum (leopard’s bane), Brunnera (Siberian bugloss) and primulas.

Rock plants

Close up of mauve and magenta aubretia plants cascading over a border edge

If you don’t prune aubretia after flowering it will become straggly and bare at the base
Image: Shutterstock

Spring flowering rock plants such as alyssum, arabis and aubretia should be cut back hard now to keep them trim and tidy.

 

Early spring bulbs & flowers

Close up of person's hand about to snap off immature seed pod of tulip

Dead head tulips and daffodils so that they don’t waste energy on developing seed.
Image: Annelise Brilli

  • Continue dead-heading daffodils and tulips but leave the foliage intact for at least 6 weeks after flowering. It is not worth doing this to ‘bedding’ tulips, which decline after the first year, but some tulips, such as Darwin hybrids, are reliably perennial and will continue to flower again next year.
  • Once the foliage is yellow, lift congested daffodils which didn’t flower well this year and replant them.
  • Fading spring bulbs which you want to keep for next season can be lifted and transplanted elsewhere to make space for summer bedding. Feed all your spring bulbs now, preferably with a low nitrogen, high potash feed.
  • Pulmonaria (lungwort) and Brunnera (Siberian bugloss) invariably get mildew at this time of the year. Simply cut all the foliage off and give them a good water and they will reward you with healthy new foliage.

 

Wildlife Gardening

Close up of a golden yellow pot marigold flower with a bee in the centre

Plants such as this Calendula (pot marigold) are important sources of food for foraging insects
Canva

  • Buy or sow insect attracting summer plants such as Nicotiana, (tobacco plant), Calendula (pot marigold), cosmos, sunflowers, salvias, heliotrope, Agastache (giant hyssop), wallflowers, Lobularia maritima (alysum).
  • Gently clear the pond of pond weed leaving the debris on the side so pond creatures can easily crawl back in.
  • “Join legions of gardeners and say “no” to the mow this May to help our bees, butterflies, wildlife and us!” says Plantlife. You don’t have to do much. Nothing in fact. Just relax in a garden armchair and let the wild flowers in your garden provide a feast for hungry pollinators. You might be amazed at what pops up in your lawn when you stop mowing. Instead of telling yourself that there’s nothing you can do to help the planet, do just this one simple thing and help to reverse the drastic decline in our insect populations.

 

 

The 10 Best Plants for April

Close up of pink cupped shaped flowers of Chaenomeles x superba ‘Pink Lady’ borne on bare stems

Chaenomeles x superba ‘Pink Lady’
Image: Canva

April is an exciting time and there is plenty to do in borders:

  • As perennials emerge, look out for losses and gaps and plan how you are going to fill them. Get new perennials in as soon as you can and sow drifts of hardy annuals into warm soil.
  • Hoick out any weed seedlings whilst they are still small but keep a careful eye out for those self-sown seedlings which you want to keep such as foxgloves. You can move these seedlings into the best positions, watering them well after transplanting them.
  • Lightly trim Mediterranean shrubs such as lavender, phlomis, santolina and Helichrysum (curry plant), nipping them back by 2.5cm-5cm to remove any frost damaged growth and keep them compact.
  • Plant up all summer flowering bulbs by the end of the month including gladioli, Anemone coronaria and lilies.
  • Once early flowering shrubs are over you can prune them if needed, this includes forsythia, Chaenomeles (Japanese quince) and Ribes (flowering currant).

1. Lamprocapnos spectabilis (Dicentra spectabilis)

Close up of Dicentra spectabilis flowers - pink heart shaped flowers hanging off horizontal stem

Lamprocapnos spectabilis (formerly Dicentra spectabilis)
Image: Canva

If you don’t yet have a corner of your garden dedicated to the spring, then now is the perfect time to plan and plant one. Whatever space you have, it’s so important to squeeze out every season of interest and Dicentra spectabilis is the perfect place to start as it’s a model spring beauty. Its only drawback is that the plant boffins have changed its name, so I now have to remember to call it by its clumsy new moniker of Lamprocapnos spectabilis. Also known as Bleeding Hearts, this plant is a real heart warmer as it is one of the first perennials to emerge, synchronising with spring tulips and providing an opening act before the main summer performance. Its fresh green, lacy foliage is beautiful in itself, and goes well with the unfurling fronds of other ferns.

The heart-shaped flowers dangle on arching racemes and their unusual shape has also earned it the nickname of ‘Lady in the bath.’ Peel back the outer petals of the flower to reveal the naked lady within! I love the plain pink form, but there are also the cherry red hearts of ‘Valentine’, whilst the simple white of ‘Alba’ will lift a dark, shady corner.

Although Lamprocapnos spectabilis is reported to need reliably moist soil, I have successfully grown it in dry silt. A native to China, Korea and Japan, its natural habitat is in rock crevices and it copes in drier soils provided it is given a shady spot. Once flowering is over, cut the whole plant down to the ground and it will remain dormant over summer, happily giving up space to summer flowering perennials and not caring if it is completely swamped by them. Lamprocapnos spectabilis doesn’t develop a woody crown so it can be left in situ for years, quickly bulking up into impressive specimens.

2. Epimedium ‘Frohnleiten’

Close up showing raceme of bright yellow, four-petalled epimedium flowers

Epimedium ‘Frohnleiten’
Image: Canva

You will want to reserve the sunniest south and west facing parts of your garden for the main summer display, but East and North East facing borders which receive sun for some but not all of the day are perfect for spring plants, as are dry spots beneath trees and shrubs. Epimedium provide excellent ground cover in these conditions, quickly forming spreading colonies. Epimedium ‘Frohnleiten’ is a lovely form. The flowers are tiny, and in other cultivars can disappear, but with ‘Frohnleiten’ they are a bright sulphurous yellow and stand out beautifully against the foliage. The foliage is evergreen but will be looking tatty by early spring. Cut it all off in March and you will be rewarded with new heart-shaped leaves decorated with fine green veining against a rusty red background.

Close up of heart-shaped foliage of Epimedium 'Frohnleiten' with rusty red colouring and acid green veining

The foliage of Epimedium ‘Frohnleiten’ offers equal interest to its flowers
Image: Canva

 

3. Euphorbia x martinii ‘Ascot Rainbow’

Close up of lime green flower bracts with red eyes of Euphorbia x martinii 'Ascot Rainbow'

Euphorbia x martinii ‘Ascot Rainbow’
Image: Thompson & Morgan

Euphorbias or spurge are such valuable plants. Their chartreuse coloured flower bracts last for many weeks and they have the ability to really make other colours sing. Many are also evergreen, providing all year colour and structure. Euphorbia x martinii ‘Ascot Rainbow’ is a real stunner, and makes a striking combination with brightly coloured tulips. Its evergreen leaves are beautifully variegated with gold edges and develop pink tinges during cold weather. The lime-green flower bracts are splashed with darker green patterning and have a dark red eye.

 

4. Erysimum ‘Bowles Mauve’

Close up of deep purple 4-petalled flowers of Erysimum 'Bowles Mauve'

Erysimum ‘Bowles Mauve’
Image: Canva

The upright, lime green flowers of Euphorbias really make other colours pop. Combine Euphorbia x martinii ‘Ascot Rainbow’ with the phenomenally long-flowering Erysimum ‘Bowles Mauve’.  This ‘perennial’ wallflower will survive the winter but it becomes horribly woody. However, cuttings strike with such ease and it is so floriferous that it’s definitely worth putting up with this drawback.

5. Brunnera macrophylla ‘Jack Frost’

Close up of the tiny, pale blue, forget-me-not flowers of Brunnera macrophylla

Brunnera macrophylla bears airy sprays of pale blue forget-me-not flowers
Image: Canva

The pretty blue forget-me-not flowers of Brunnera macrophylla ‘Jack Frost’ associate well with the sulphur yellow of Epimedium ‘Frohnleiten’ and its silver patterned leaves continue to provide interest long after the flowers have finished. You could even pair its silvery tones with a dark purple heuchera, such as ‘Plum Pudding.’

Close up of heart-shaped leaves of Brunnera macrophylla 'Jack Frost' showing green leaves with silvery white colouring between leaf veins

Brunnera macrophylla ‘Jack Frost’ has handsome foliage
Image: Canva

6. Pulmonaria ‘Raspberry Splash’

Close up of Mauve and raspberry flowers and silver spotted lanceolate foliage

Pulmonaria ‘Raspberry Splash’
Image: Terra Nova Nurseries

Pulmonarias produce early flowers which provide an important source of food for hungry bees awakening from hibernation. Pulmonaria ‘Raspberry Splash’ bears clusters of tubular, mauve to raspberry pink flowers on long stems above rosettes of silver-spotted leaves. As with all Pulmonarias, after flowering the leaves often get mildew but this is easily remedied by simply cutting them down to the ground. Water well and the plant will quickly bounce back with a fresh crop of lovely new leaves.

7. Ribes sanguineum ‘King Edward VII’ 

Close up of dark pink pendulous flower clusters of Ribes sanguineum 'King Edward VII'

Ribes sanguineum ‘King Edward VII’
Image: Dreamstime

The two shrubs which I enjoy most at this time of the year are the flowering quince, chaenomeles, and the flowering currant, ribes. I am constantly popping out to admire my Ribes sanguineum ‘King Edward VII’ which is covered in pendulous raspberry-red blooms that never fail to impress me. The bees love it too. If you fancy something a little different, plump for Ribes x gordonianum. The flowers are bi-coloured a subtle pink and creamy yellow which is exquisite.

8. Chaenomeles x superba ‘Pink Lady’

Close up of cup-shaped pink flowers of Chaenomeles x superba ‘Pink Lady'

Chaenomeles x superba ‘Pink Lady’
Image: Canva

Striking an oriental note is Chaenomeles x superba ‘Pink Lady’ with its gorgeous candy-pink blooms set off with golden anthers. With bold, cup shaped flowers adorning dark, twiggy stems, Chaenomeles are bursting with spring impact. They offer a palette which includes reds and pinks at a time when the garden is often dominated by blues and yellows. Chaenomeles look wonderful trained onto walls or trellis which shows off their blooms, but they can also be grown as free standing shrubs or even used as flowering hedges.

9. Exochorda x macrantha ‘Niagara’

Exochorda x macrantha 'Niagara' shrub covered with abundant pure white flowers

Exochorda x macrantha ‘Niagara’
Image: Van Son & Koot

Meanwhile, just around the corner, I’ve been coveting my neighbours Exochorda x macrantha ‘Niagara’ which is already smothered in masses of white blooms. ‘Niagara’ is a much improved version of the old cultivar, ‘The Bride’ with more compact and manageable growth which is perfectly suited to smaller gardens.

10. Viburnum ‘Kilimanjaro Sunrise’

Close up of white lace-cap flowers of Viburnum 'Kilimanjaro Sunrise'

Viburnum ‘Kilimanjaro Sunrise’
Image: Van Son & Koot

The viburnums are also just starting to unfold their buds including one of the best selections, Viburnum ‘Kilimanjaro Sunrise’. Other forms of Viburnum plicatum have a very broad habit which is hard to accommodate in smaller gardens, but this one grows neatly upright, its tiered branches clothed in abundant lace-cap flowers which are prettily blushed with pink. This is a hard-working shrub which really earns its place, as in the autumn it rewards again with fiery red and orange tinted foliage. For the same qualities but in an even smaller package, plump for Viburnum plicatum ‘Watanabe’, which will happily grow in a pot or narrow border.

Given some sun, all three of these shrubs are easy-care plants and will even tolerate heavy clay. Like all early flowering spring shrubs and climbers, they are able to flower so early because their flowering wood grew last year. For this reason, any pruning should be carried out directly after flowering.

I shall definitely be treating my spring garden to an Exochorda x macrantha this year –  which April flowers will you be plumping for? Whatever you choose, after planting keep an eye on the watering – our springs are becoming increasingly warm and dry. Give your new plants a good soaking every one or two weeks until they become established.

Slug and Snail Control: The Ultimate Guide

Slug on leaf

Image: Canva

The sight of tender shoots pushing through warming spring soil lifts the heart of every gardener. After weeks of anticipation the garden is finally moving. We rush to the greenhouse and start frantically sowing, gleefully admiring trays brimming with new seedlings. Hoes and rakes are joyfully unleashed from dark sheds, the soil is tilled, seeds are scattered. At the end of the day, as sunlight rakes across our tired but satisfied brows, visions of perfect lettuces, juicy peas and drifts of flowering annuals dance before our eyes. Spring – the season of optimism! 

But behind that optimism is a hidden anxiety. There is something nasty lurking under the leaf litter at the back of your mind. And suddenly, in one damp night, swathes of innocent baby seedlings are ruthlessly massacred, eager buds nipped off in their prime, precious young shoots ripped to shreds. Yes! Those monstrous molluscs have returned: Slugs and snails.

Spring into action against slugs and snails

Tray of tomato seedlings

These seedlings are soft and leggy and provide excellent fodder for slugs and snails
Image: Canva

As temperatures rise, slugs and snails emerge from hibernation where the ability to super-cool their bodies has protected them from freezing. Meanwhile, generations of eggs laid in the autumn are busy hatching throughout April and May. All of these animals emerge with raging appetites and, as the spring garden serves up a banquet of soft and succulent food, who can blame them for gorging at the feast?

From 1 April 2022 it is now illegal to sell and use metaldehyde slug pellets. So, whether you like it or not, this particular weapon can no longer be part of your armoury against the gardener’s number one enemy. British gardeners have been using some 650 billion slug pellets per year – and there is no doubt about it – they worked. Sadly, they worked rather too well. Only a small amount of metaldehyde is needed to poison or kill non-target animals and as the pellets included a bait, every animal which occupies your garden – birds, frogs, toads, newts, hedgehogs, slow worms, mice, even your pets – was at risk.

The good news is that there are many alternative and safe slug and snail deterrents. But which actually work? Being prepared in advance of the enemy is crucial – so let’s examine the options – both silly and sensible – and whilst we’re at it, take a closer look at these much-maligned molluscs, delving into dark, damp corners to uncover some of their slimy secrets.

Hand to hand combat

close up of booted foot about to squash a large orange slug

Some gardeners are more ruthless than others!
Image: Shutterstock

Post-war gardeners were made of stern stuff. My mum would pluck a slug from the ground, confront it eyeball to eyestalk and then abruptly slice it in two with her secateurs. I don’t count myself as a squeamish gardener, but this is a bit too much for my stomach. Neither am I that fond of her other strategy: the nightly ritual of slug-stalking with a salt cellar which the following morning would leave hazardous pools of slug-gloop along the path awaiting my young unshod feet.

I am however partial to the satisfying scrunch of crushing snails beneath my boot. But I confess to being a cowardly killer, as I prefer not to look too closely at my victims as they flinch under my boot. As well as their eyes, snails have light sensing cells dispersed all over their outer skin which enables them to quickly react to the hovering shadow of a murderous hand or boot. Other suggested molluscan murder methods include collecting them all in a bucket. Exactly what you do with your bucket of slugs and snails afterwards I do not know or care to contemplate.

Close up of slug with clutch of translucent eggs

Slugs lay up to 200 eggs per square metre
Image: Shutterstock

Are these methods effective? Well, they certainly satisfy the gardener’s thirst for revenge. But do they make any significant dent in the population of molluscs which are busy consuming your garden? The problem is, although you may not find these molluscs attractive, they find each other positively irresistible. Both slugs and snails are hermaphrodite, which is a distinct advantage for such slow animals that might otherwise have difficulty bumping into the ‘right’ partner; and both enjoy very elaborate courtship rituals which can go on for hours. In fact, gastropods have voracious appetites for love as well as food and can boast of very adventurous sex lives, so adventurous that the next time I look a snail in the eye both of us might blush. All this romance means that the average garden has 20,000 slugs and lay as many as 200 eggs per cubic metre. So I’m afraid you may have won the battle, but the slugs have definitely won the war.

Create a slug zone

Close up of gloved hand holding a slug and in the background a bucket of slugs surrounded by tomato plants

Slugging it out with a bucket load of slugs is not for the faint hearted
Image: Shutterstock

One suggestion I have come across on the internet is to ‘deliberately attract slugs’ to an area of your garden away from your target plants and then to go out and collect them at night. Gardeners World suggests “using something they’re attracted to – old veg leaves, dried cat food, bread rolls, oats or bran”. To me, this sounds like a very good way of attracting rats as well as molluscs and given that rats have a considerable speed advantage, I suspect that both slugs, snails and the gardener are likely to end up disappointed by the results.

It also raises the same tricky problem encountered above –  what do you do with your bucketful of slugs and snails? One traditional solution has been to lob them over the neighbour’s fence. If you are having a boundary dispute with your neighbour this will probably give considerable satisfaction, until that is, those cunning slugs and snails find their way home. Unfortunately, scientists have discovered that snails are equipped with a homing instinct. This means they need to be hurled at least 20 metres away to ensure they won’t find their way back – a feat which would require the arms of an Olympic shot putter.

I’m left with a sinking feeling that this project is doomed to backfire – the neighbour is enjoying a garden freed of slugs, snails and rats whilst I’m saddled with a bucketful of slimy slugs and snails and a cold walk in the night to dispose of them.

 

Beer Traps

Research by Garden Organic found that slugs enjoy beer but turned their tentacles up at red and white wines, Cava, cider, orange squash and water
Image: Shutterstock

Beer traps are a well-known traditional slug and snail deterrent but they are a method which I definitely can’t advocate. Slugs and snails can sniff out fermenting beer from long distances and will be attracted to your boozy garden often without actually drowning in the beer, so you are likely to end up with a bigger population of molluscs than you started with. Meanwhile, a host of other beneficial insects will also be attracted to your traps and meet a sticky end. Personally I think it’s a waste of beer. Let’s move on!

Eggshells, sawdust, coffee grounds, wood ash, human hair, grit, etcetera, etcetera

Close up of person holding trowel and scattering wood ash between rows of lettuce

Disappointingly, natural home-made barriers such as wood ash are less than useless on slugs and snails
Image: Shutterstock

Sorry, but all of these methods are perfectly useless. This is because slugs and snails are equipped with a super power: slime! Acting as both an adhesive and a lubricant, this slime has miraculous elastic properties and the ability to change its consistency when pressure is applied. Get slug slime on your skin and you will find it a devil to wash off due to its supreme stickiness and impressive ability to hold water. Scientists have even taken inspiration from slug slime to develop medical glues which will bond wet tissues and stem bleeding. Even hedgehogs find slug slime troublesome to deal with. This video by Julia from The Hedgehog Diaries shows a hedgehog de-sliming its slug meal by rolling it on the ground!

Dr Hodgson of Exeter University has discovered that snails use up to 30 percent of their energy in slime production and reports that ‘snails move in convoys, piggy-backing on the slime of other snails to conserve energy’. Slime not only assists movement but is also designed to prevent injury when molluscs move over rough surfaces. Their sublime slime means that slugs and snails can happily glide across razor blades and they will be laughing off your puny human efforts to deter them with mere eggshells.

Wool pellets

Close up of grey slugs making slime trails across a piece of wood

Slime is a super power! But wool pellets are an effective weapon
Image: Shutterstock

Put aside your eggshells and coffee grounds and try wool pellets instead. If you find wool jumpers itchy, then so do slugs! Wool fibres are highly hygroscopic, meaning they absorb moisture. This, plus natural sands and grits in the wool and salts from sweaty sheep, sucks up slime and causes irritation to the slugs so they crawl off in search of easier food.

After placing them around the base of the plant the pellets are thoroughly watered. This causes them swell and bind together forming a dense matt which isn’t disturbed by wind or rain. Although wool pellets are quite pricey the mat will last for up to 12 months and has the bonus of acting as a mulch which will supress weeds and retain moisture, breaking down naturally in the soil to slowly release nutrients.

I planted out a lot of sunflower seedlings last year and tired of watching each one being felled by marauding molluscs I tried wool pellets. I’m pleased to report that they were a resounding success. They need to be piled up in a wide, thick barrier ( at least 4inches (10cm) wide and a few inches deep) so are good for protecting individual specimens such as hostas, delphiniums, sweet peas and lupins but not so useful for long rows of seedlings.

Grazers G2 slug and snail repellent

Bottle of Grazers concentrate and a bottle of Grazers ready to use spray

Grazers is available as a concentrate or a ready-to-use spray
Image: Thompson & Morgan

Grazers offer a range of organic pest-deterrents in a liquid form which are based on calcium, with different formulations tailored to different pests. I’ve certainly had success using Grazers to deter rabbits and pigeons, so their slug and snail formula looks a promising bet. What I have found is that for Grazers to be successful you need to apply it thoroughly and repeat spray at intervals. How often you need to re-apply will largely depend on rainfall, time of year and growth rates so it varies from several days to a few weeks. Fast growing young plants with soft tissues which are subject to heavy spring rains will need more frequent applications. If you are only treating one or two plants then a handheld sprayer is fine but keen gardeners would be well to invest in a pressure sprayer for this task. This allows you to make up a tank of mix and then grab it and speedily spray your vulnerable plants whenever required.

The calcium contained in Grazers is absorbed through plant leaves and stems into plant cells. It doesn’t kill slugs and snails but makes plant tissues distasteful so they will seek other food sources. It takes a little while for the calcium to be absorbed and moved through the plant, so if you are transplanting vulnerable young plants from the greenhouse to their outdoor positions, it’s a good idea to treat them with Grazers for a few days prior to doing so. Price wise, Grazers is a relatively economic option, but it obviously requires more labour than putting down wool pellets. However, it’s better suited to large areas of crops or ornamentals.

A note on gastropod grazing habits

Not for nothing are slugs and snails known as ‘gastropods’ –  literally an ‘eating foot’. These animals have evolved into highly efficient munching machines and they are not easily put off their meals. Grazers is the only commercial product which makes plant tissues distasteful to them. Both slugs and snails are equipped with a ribbon-like tongue called a radula which is covered in thousands of tiny teeth, neatly arranged in rows. In fact, the garden snail has about 14,000 teeth! By grinding the radula against its horny jaw, the slug or snail rasps at its food. This causes the ragged abrasion of plant surfaces which is characteristic of slug and snail damage. It also enables them to grind their way through tougher foods like your potato tubers. They may lose a few teeth in the process, but new ones quickly regrow in their place. Once past the mouth food enters a holding bay or ‘crop’ so slugs and snails can happily ‘eat on the run’, bolting down your entire tray of seedlings, rapidly followed by seconds and pudding before retreating beneath the tray to digest dinner at leisure, in the dark and hidden from predators.

 

Organic-approved slug pellets

Close up of slugs covered in blue pellets

Even organic-approved slug pellets should be used sparingly, not like this!
Image: Shutterstock

What’s in organic slug pellets and how do they work?

Numerous brands of organic-approved slug pellets are available including:

All of these products are based on ferric (iron) phosphate which is bound to a cereal-flour based bait. Iron phosphate affects the metabolism of calcium in the gut of slugs and snails causing them to stop feeding and die within three to six days. Any uneaten pellets will slowly break down releasing phosphate and iron which will be taken up by plants as nutrients.

Effect on earthworms

These pellets are harmless to mammals but there is one downside – they can be harmful to earthworms. As well as ferric phosphate, the pellets contain chelating agents which are toxic to earthworms that consume them, causing them to feed less, lose weight and die. The power of humble earthworms in maintaining a healthy soil ecosystem is not something to be casually dismissed, so it is essential that gardeners use these pellets responsibly.

Application

I wince when I see people pour gluts of pellets all over the place as this really isn’t necessary – the pellets are baited and so will attract slugs and snails to them. These molluscs are equipped with incredibly sensitive taste and smell organs in their lips and tentacles which can detect minute chemical traces in their environment. Slugs and snails find potential mates by sniffing out and following mucus trails and will back track along their own scented trails to find their way home. So, if you are going to use organic slug pellets, do so sparingly, just using 4 or 5 in an area the size of an A4 piece of paper.

 

Nematodes: a slug’s nemesis

Magnified image of a translucent nematode worm on a blade of grass

Magnified image of a nematode worm
Image: Canva

What are nematodes and how do they work?

Professional gardeners have been using living organisms to control pests, known as ‘biological control’, for many years. They are now readily available to amateur gardeners, and if you haven’t tried them yet then you are definitely missing a trick! Nematodes are microscopic worms which are naturally present in the soil and act as parasites on other living organisms. The great thing about them is that they are host-specific and so non-target species are left unharmed.

Close up of slug with swollen mantle having been infected by nematodes

Slugs infected by nematodes develop a swollen mantle
Image: Ion Colino – http://areitzsoroa.blogspot.co.uk/2010_12_05_archive.html, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=55026740

There are nematodes for a whole range of pests and they all have distinctly unpronounceable and forgettable names. Phasmarhabditis hermaphrodita is the one for slugs, conveniently sold under the moniker ‘Nemaslug’. These tiny worms with a big name are certainly the slugs nemesis. They enter the slugs body through its breathing pore, multiplying rapidly and causing them to develop a swollen mantle. The sick slug immediately goes off its food and often remains underground. So, although it takes between 7 to 21 days for it to keel over and die, damage to your precious plants is immediately reduced. Once the slug dies the nematodes tuck in and feed off its remains. They go on to produce another generation of hungry slug-killers which travel through the soil to hunt down new slug hosts.

Application and timing

Nemaslug is effective but it must be applied correctly and timing is crucial. The sachet containing the nematodes is mixed into water and applied onto the soil using a watering can or garden hose applicator. The soil temperature needs to be consistently above 5°C but you also want to apply it as early as possible in the spring to catch the first generation of young slugs before they turn into larger adults which are more resistant to infection. One application provides up to 6 weeks of control so, several applications are needed during the growing season. As Nemaslug is a live product with a shelf life, (it has to be stored in a refrigerator on receipt), the packet includes a small calendar to record applications and remind you when to order your next batch.

Good against slugs but not snails

Close up of brown lipped snails on plant stems

Nematodes attack all slugs but are not very effective on snails, such as these attractive brown-lipped ones
Image: Canva

Nemaslug is effective on all pest slug species and grey field slugs are especially susceptible which is good news as they are the most damaging of all garden slugs. However, if snails are your biggest enemy then Nemaslug won’t be much use. Although nematodes can kill snails, they tend to evade infection due to their largely surface-dwelling nature.

Being ugly, slimy and homeless, slugs have few fans, and seem to come in for the most blame. Meanwhile the snail, with its ingenious and pretty armour, its shy ‘peak a boo’ behaviour and the fact that the shell provides a convenient and dry hand hold for curious humans, has a slighter cuter reputation. However, of the 30 plus species of slugs in Britain, only 4 are really garden pests feeding off living plant material, the remainder prefer munching on dead organic matter. If you have a limey soil, point the finger of blame at snails instead. They prefer calcareous soils which provide the necessary calcium to build their shells.

Not so effective on heavy soils

Nemaslug is more effective in freely draining soils than heavy clays, as these allow nematodes to easily move about and find their hosts.

Harmless to earthworms

Nemaslug has the advantage over organic pellets in that it continues to work well in wet weather and numerous experiments have demonstrated that it is completely harmless to earthworms along with insects and other organisms.

Slug and snail control: A military strategy

Use a combination of methods

In the war against slugs and snails it pays to have a co-ordinated strategy, employing all of your cultural, chemical and physical controls to defeat these resilient garden adversaries. Don’t rely on just one of the methods above, which all have their advantages and disadvantages, but use them in tandem. Use an early application of nematodes to protect vulnerable root crops, such as potatoes, across a wide area of ground. Apply Grazers to leafy veg such as brassicas. Meanwhile, protect your ornamentals with Ferric phosphate and wool pellets.

Grow your seedlings on

Grow seedlings on until they have reached a reasonable size and their stem and leaf tissues have toughened up a bit before planting them out. Greenhouses can quickly get too hot in spring sunshine even when the ambient temperature is cold. Seedlings raised in excessively warm conditions grow very soft and leggy – perfect food for slugs and snails. Ventilate your greenhouse as much as possible to keep temperatures at a reasonable level and harden off seedlings in a slug-protected area (see below) before they go outside.

Concentrate your efforts

Pay especial attention to your nursery areas where seedlings and young plants are placed and concentrate your efforts on these zones, using Ferric phosphate pellets sparingly to protect them.  Reduce any hiding places in these areas by keeping them tidy and removing debris and leaves. Pay attention to crop margins which are adjacent to nearby cover such as hedges or long grass.

Check your seed trays

Slugs and snails love to hide beneath seed trays and pots so check underneath them everyday.

Don’t use high nitrogen fertilisers too much

Slugs and snails will go for soft juicy growth which is exactly what high nitrogen fertilisers promote. Aim instead for slow, steady growth. Where necessary use organic slow-release fertilisers or specialised feeds such as Chempak Low Nitrogen (good for firming up vegetables and vulnerable plants such as lupins and delphiniums), or Chempak High Potash (to encourage flowering rather than leaf and stem growth).

Water in the morning

This will enable the ground and foliage to dry out before foraging molluscs come out at night.

Be vigilant during wet weather

After every bout of rain check and renew your slug and snail defences where necessary.

Encourage wildlife

Close up of a thrush with a snail in its beak

Slugs and snails are a necessary part of a thriving ecosystem. Look after your allies in the war against them
Image: Shutterstock

All of the animals listed below eat slugs and snails, so it makes sense to recruit them as your allies. Our wildlife gardening guides provide plenty of tips for encouraging them into your garden.

  • Hedgehogs
  • frogs
  • toads
  • newts
  • slowworms
  • birds
  • ground beetles
  • centipedes
  • shrews
  • mice

Avoid the plants most vulnerable to slugs and snails

Close up of blue, white and mauve delphinium flower spikes

Sluggish gardeners who don’t have the energy for a war against gastropods may prefer to avoid susceptible plants such as these delphiniums
Image: Canva

If slug and snail warfare isn’t your thing, then don’t bother with the plants listed below :

  • Beans
  • Celery
  • Clematis
  • Dahlia
  • Delphinium
  • Doronicum
  • Gerbera
  • Helenium
  • Hollyhock
  • Hosta
  • Hyacinth
  • Lettuce
  • Lilies
  • Lupin
  • Pansy
  • Peas
  • Potato
  • Primula
  • Soloman’s Seal
  • Sweet peas
  • Tulips


Slugs and snails are here to stay!

Close up of slug coming out of the spout of a watering can

Molluscs have been around for 500 million years, which has given them ample opportunity to perfect the art of annoying gardeners
Image: Canva

There is no way of completely eradicating slugs and snails and if we could, our gardens would be in a terrible mess. Slugs and snails are primary consumers, munching through organic matter, fungi and algae and making it available to smaller organisms. Without them, we would literally be surrounded by rubbish. Think of them as one of nature’s dustmen, indiscriminate but efficient. They also form an important part of the garden eco-system, providing food for all sorts of animals. Concentrate your efforts on young seedlings and the most vulnerable plants, and accept that slugs and snails will always love your garden as much as you do!

Magnificent Magnolias

Pink magnolia flowers against a blue sky

Get out into gardens now and enjoy the spring performance of magnolias in full bloom
Image: magicflute002/Canva

Cossetted within their velveteen coats, the buds of magnolia trees are just beginning to unfurl their voluptuous, vase-like blooms and wow crowds with a spectacular spring performance. If you’ve ever gasped in awe at a magnolia in full bloom but dismissed them as too difficult to grow yourself, then think again. Modern cultivars are increasingly versatile and reliable, with many being suitable for smaller gardens and even container growing.

Ancient Beauty

Dinosaurs tramping amongst dull ferns and horsetails were probably the very first creatures to appreciate the beauty of magnolias!

Magnolias are a very ancient genus and botanists believe that the very first flowers to evolve on earth were similar in appearance to the magnolias we see today. These first flowers evolved before winged insects and were pollinated by beetles which were attracted to the flowers by their fragrance, edible petals and pollen. Millions of years later modern magnolias still have deliciously fragrant flowers, with scents of lemon, honey and vanilla. Not only beetles enjoy their edible flowers but also humans – the buds are valued in Asian cuisines for their unusual perfumed, gingery flavour.

The Ice Age swept away the European magnolias leaving them stranded in the Americas and Asia. In South America, magnolias have been appreciated as garden plants since the Aztec Civilisation, when the creation of pleasure gardens was a popular pastime for the nobility. Now teetering on the edge of extinction, Magnolia dealbata was cultivated by Aztec gardeners who valued the tree not only for its beauty, but also its medicinal uses. Scratch the bark of a magnolia and you will discover that it has a lovely balsamy smell, an indication of the complex compounds which have been used in traditional medicine for thousands of years.

It wasn’t until the 17th century that the first magnolias were introduced into Europe from eastern North America. All of the American species are later flowering, and include Magnolia grandiflora; an impressive evergreen species with huge, cupped flowers.

Large white cupped flower of Magnolia grandiflora against background of dark green leaves

Magnolia grandiflora was one of the first magnolias to be introduced to Europe
Image: Rixie/Canva

At the beginning of the 20th century magnolias became even more exciting. Two intrepid plant hunters, Ernest Wilson and George Forrest, returned from China with a magnificent cache of Asian magnolias. After these species were brought back to Britain, breeders began creating wonderful hybrids such as Magnolia x soulangeana, which is now one of the most popular magnolias in UK gardens.

Magnolia Myths

Towering conical shaped Magnolia campbellii tree

Don’t be put off by huge specimen magnolias, there are plenty of varieties for small gardens
Image: Magnolia campbellii, susipangrib/Canva

There are numerous myths surrounding the cultivation of magnolias which deter people from growing them. They have an undeserved reputation for being difficult, only growing on acid soils in very warm locations and taking decades to flower before reaching huge proportions which can’t be tamed by pruning. As a result, they have become associated with large country gardens in southerly locations where towering specimen trees of Magnolia campbellii flaunt their blooms dangerously early in late winter, thoroughly intimidating ordinary gardeners in charge of small plots in cooler climates. Let’s challenge some of these magnolia myths and make a place for these sublime shrubs in even the humblest gardens!

Magnolias aren’t too big for your garden

Magnolia stellata

Magnolia stellata
Image: Shutterstock

You don’t need to own a country house to grow a magnolia! There are plenty of options for small gardens and even container growing.

Magnolia stellata is the perfect candidate. Forming multi-stemmed shrubs, they are easily accommodated in small gardens and patio containers. Their open, starry flowers with gently drooping petals come in pink or white. They look gorgeous dappled with spring sunshine.

Magnolia 'George Henry Kern', pink goblet shaped blooms

Magnolia ‘George Henry Kern’
Image: Dreamstime

For small magnolias with the more classic, goblet-shaped blooms, both Magnolia ‘Satisfaction’ and ‘George Henry Kern’ are rewarding choices, providing delicately pink-flushed flowers which contrast with a paler inside.

Magnolia 'Susan'

Magnolia ‘Susan’
Image: nickkurzenko/Canva

Magnolia ‘Susan’ also possesses the typical upright flowers, but the form is slender and vase-like with the petals artfully twisted. ‘Susan’ is an RHS award-winner and it’s impossible not to fall in love with the deep purplish pink of her flowers.

Magnolia liliflora 'Nigra'

Magnolia liliflora ‘Nigra’
Image: Ian Redding/Canva

But if you are one of those people who falls deeply for darker tones, then the slender, lily-shaped flowers of Magnolia liliflora ‘Nigra’ will have you swooning whilst Magnolia ‘Genie’ flaunts the same romantic colours but in a more voluptuous silhouette.

Magnolia 'Genie'

Magnolia ‘Genie’
Image: Dreamstime

 

All these choices are excellent for pots. Growing magnolias in containers allows you to position them close to a window where you can appreciate their spring flowers indoors. Containerised magnolias can also be used as the focus of a stunning spring patio display surrounded by pots of early-flowering bulbs such as crocus and daffodils.

Magnolias don’t all need acid soil

Whilst many magnolias do need acid conditions, there are worthy choices for those of us who garden on neutral or alkaline sites, providing the soil is moist and you prepare your planting hole with care, enriching the planting mix with some organic matter.

Magnolia x soulangeana

Magnolia x soulangeana
Image: johnandersonphoto/Canva

Living on the South Downs, I am surrounded by gardens with wonderful specimens of Magnolia x soulangeana which are happily thriving on shallow chalk. An RHS award winner, Magnolia x soulangeana slowly grows into a broad tree with a domed crown and elegantly spreading branches which carry masses of flowers in spring. The large blooms are carried with great poise, like goblets held upright to toast the spring, and are available in pink or white. Magnolia x soulangeana defies the reputation which magnolias have for being difficult, as this is a thoroughly unfussy tree.

Magnolia stellata and its relative Magnolia kobus will both cope with alkaline conditions, as will the hybrid between the two: Magnolia x loebneri. Both Magnolia x loebneri ‘Wildcat’ and Magnolia x loebneri ‘Mags Pirouette’ are compact varieties suited to smaller gardens. ‘Mags Pirouette’ is distinguished by the pleasing form of its double, white flowers, with its outer petals longer than the inner ones.

Other magnolias suited to neutral to alkaline soils are Magnolia grandiflora and Magnolia wilsonii.

Magnolias don’t take decades to flower

Magnolia 'Fairy Cream'

Magnolia ‘Fairy Cream’
Image: Van Son & Koot

If you want to grow one from seed, then yes, you may be waiting for up to 40 years, but established potted plants on grafted rootstocks will reward you with blooms within 3 to 5 years. Some are even faster than that. Magnolia ‘Fairy Cream’ is renowned for its vigorous growth, producing spring blooms on relatively young plants. It’s also usefully petite and an ideal specimen for a small border or container.

Magnolias don’t only flower in the spring

Magnolia grandiflora is often admired in the gardens of large estates where their huge, glossy, evergreen leaves sparkle on the vast, sun-baked walls of stately homes. In late summer and early autumn it is decked with large creamy-white flowers with an intoxicating, citrusy fragrance. Fortunately, those clever plant breeders have come up trumps again – with a cultivar for those of us who don’t have a mansion but are lucky enough to have a south or west facing wall in a sheltered position.

Magnolia grandiflora 'Alta'

Magnolia grandiflora ‘Alta’
Image: Shutterstock

Magnolia grandiflora ‘Alta’ makes a fabulous specimen tree. Its narrowly columnar habit means that it’s much more easily accommodated than the species, only spreading to a comfortable 1.5 to 2.5 metres. The handsome, glossy leaves are also slightly narrower than the species but have the same coppery, felted undersides. However, there are no compromises when it comes to flowers, and in late summer Magnolia ‘Alta’ produces luscious, cup-shaped blooms of pristine white.

Magnolia wilsonii

Magnolia wilsonii
Image: Frank Matthews

The plant hunter, Ernest Wilson, gave his name to the rare Magnolia wilsonii which flowers in May and June. This AGM winner has more bashful blooms than the upward-facing flowers of most magnolias. The flowering heads of Magnolia wilsonii nod down shyly, but peer up into them and a prominent central green cone surrounded by crimson stamens is revealed as well as intense perfume. These pristine flowers are nature at its most simple and stylish.

Better still, both Magnolia grandiflora and Magnolia wilsonii don’t demand acid conditions and will happily grow in gardens with neutral to alkaline soils.

Magnolias aren’t all pink or white

Magnolia 'Yellow Bird'

Magnolia ‘Yellow Bird’
Shutterstock

For the past 30 years, breeders have been chasing after the elusive yellow magnolia. Only a few disappointing American species have shades of yellow in their unspectacular blooms and these are all late flowerers. But magic tricks by clever growers have eventually turned up alchemist’s gold – transforming these yellow American plain janes into Asian spring beauties with stunning primrose-yellow blooms. Due to their American parentage, both Magnolia x brooklynensis ‘Yellow Bird’ and Magnolia ‘Daphne’ flower slightly later than other spring magnolias in April/May, so the flowers are at much less risk of frost and cold winds and therefore longer lasting.

Don’t Miss the Magnolia Season!

Magnolias are a seasonal spectacle which is not to be missed. Grasp the opportunity to get out and visit open gardens in March and early April to enjoy these divas. But be inspired not intimidated by them and plant one in your garden this spring. You won’t regret it!

Top Tips for Magnolias

  • They like moist soils which don’t dry out in summer and are good for heavy clays. However, Magnolia x soulangeana and Magnolia stellata will tolerate drier soils.
  • Mulch them regularly during the first few years to maintain a moist root ball.
  • They are hardy trees but avoid cold winds and frost pockets.
  • They are best in a position with full sun, although they will tolerate some light shade.
  • As with all trees and shrubs avoid planting too deep. When you have finished the root flare should be fully visible.
  • To encourage the development of strong roots, provide a low stake which is no more than 1/3 the height of the tree.
  • If rabbits are a problem, provide a rabbit guard. Rabbits are drawn to magnolias because of their strong smelling sap.

Houseplant Doctor : Answers to Top Houseplant Questions

A stethoscope, pencil and notepad and some leaves on a table

Image: Shutterstock

From crispy leaves to soggy succulents, our Houseplant Doctor gives expert answers to your top houseplant questions.

How often should I water my houseplant?

Brass watering can with Peperomia houseplant

Image: Thompson & Morgan

There is no fixed rule because how often you need to water your houseplant depends on a host of environmental factors (light, temperature, time of year) and the individual species. Bear in mind that overwatering is often more fatal than underwatering as most plants have natural strategies to cope with short periods of drought but are less able to survive flooding. If you find watering a chore there are plenty of dry loving plants which cope well with neglect. For more information on watering see our Houseplant Watering Guide.

Why have the leaves of my houseplant gone yellow?

Dracaena houseplant with yellowing leaves

Leaf yellowing can often be caused by overwatering
Image: Dracaena from Thompson and Morgan

Observe whether it is the leaves at the top or bottom which are showing signs of yellowing.

The lower leaves of your plant may occasionally go yellow and drop and this is quite a normal part of the plant growth process. However, if a lot of the leaves are affected then environmental factors are to blame. Often, lower leaf yellowing is a sign of incorrect watering, most frequently overwatering. Tip your plant out of its pot and check the root ball. If necessary, dry it out thoroughly by standing it on a bed of newspaper.

When the upper leaves of a houseplant go yellow this can be an indication of nutrient deficiency caused by watering with hard water or by lack of nitrogen in the compost. Nutrient deficiencies are often indicated by a distinct pattern of discolouration known as ‘interveinal chlorosis.’ This means that the leaf veins remain dark green whilst the tissue between the veins yellows or becomes pale. Treat your houseplant to a liquid feed and see if the problem improves.

If the leaves have gone yellow on the side which is away from the window, then lack of light could be the issue. Turn your plants regularly or find them a brighter spot.

How do I choose the right plant?

An arrangement of lots of different houseplants

There are so many different houseplants to choose from it can be difficult to know where to start
Image: Thompson & Morgan

Firstly, decide on where you are going to put your houseplant. If you have a bright room which is south or west facing, then your choice is unrestricted. But if you want a plant for a north-facing room which doesn’t get direct sunlight, you will need to be more careful and choose plants which can cope with lower light levels. For more information see our Houseplant Lighting Guide.

Secondly, make a realistic assessment of your level of gardening experience and how much time you have. There are a vast number of easy to maintain plants, see our Top Ten Easiest Houseplants. Once you have decided on the environment and level of maintenance then you can get creative about decorating with plants.

Should I water my plant from above or below?

Close up of a lilac and white African Violet

Some houseplants, such as this African Violet, are happier being watered from below
Image: Saintpaulia ‘Anthoflores Edith’ from Thompson & Morgan

There are some houseplants which are much happier with bottom watering. This includes dry loving species which are prone to root and stem rots such as cacti and succulents. Other plants do not like water on their leaves or crowns including Saintpaulia (African Violet), Gloxinia (Sinninga speciosa) and Cyclamen.

With these plants you should always seat the pot in a saucer. After filling the saucer with water leave the plant for about half an hour to absorb the water. Don’t leave them to sit in water for long periods and allow the plant to drain fully after watering.

The majority of other houseplants are fine with watering from above.

Which houseplant can I put in a dark room?

Aspidistra plant in white pot on table in living room

Aspidistra are able to cope with low light levels
Image: Thompson & Morgan

Plants can’t survive without light but Aspidistra elatior (Cast Iron Plant) is especially tolerant of low light levels as its natural habitat is the deep, dry shade of the forest floor. Low light levels will slow down plant growth so you can compensate for this by treating your plant to a lighter spot for at least some of the growing season.

What are the easiest houseplants to grow?

A mixed arrangement of houseplants

Low maintenance houseplants back row from left: Zamioculcas zamiifolia and Monstera deliciosa
Front from left: Aloe vera, Aloe zebrina, Echeveria, Sansevieria trifasciata, Spathiphyllum ‘Torelli’
Image from Thompson & Morgan

The three top bombproof houseplants are Aspidistra elatior (Cast Iron Plant), Sansevieria (Mother in Law’s Tongue) and Zamioculcas zamiifolia (ZZ plant). All of these will tolerate a substantial amount of neglect and you can read more about them and other low maintenance plants in my Top 10 Easiest Houseplants.

7. How do I know if a plant needs repotting?

Person potting up a Sansevieria on a table

Image: Thompson & Morgan

It’s important not to repot your houseplant unnecessarily as it could result in plants becoming overwatered. Generally, houseplants enjoy being quite snug in their pots. Be especially careful with dry loving species such as cacti and succulents and plants which have naturally shallow root systems. If your plant is growing happily, leave it alone!

When repotting is needed, it will become difficult to water your plant. The root ball will be so congested that water and liquid fertiliser fails to penetrate. Roots will also poke out of the drainage holes which might make it difficult for you to release the plant from its pot. Growth is slowed down or halted.

Tip your plant out of its pot and examine the root ball. The plant is pot bound if the root ball is very dense, with roots circling round and round the pot so that there is little compost visible in the bottom third.

Do any potting up early in the growing season when your plant is in active growth and will have time to expand into its new pot long before winter dormancy. Bear in mind that potting up will cause your plant to grow larger. If this isn’t wanted, then lightly trim the bottom of the roots instead. When you do pot up don’t reach for an extra-large pot. Choose a container which is only 1-2cm in diameter larger than the existing pot. Moderate your watering regime afterwards as until the plant roots have expanded into their new pot they will be surrounded by a layer of wet compost. Be sure to use the correct compost for your plant type; most houseplants enjoy a free-draining medium.

Why has my houseplant grown tall and spindly?

This is most likely a problem with lack of light. Other tell-tale signs are uneven growth, with the plant stretching towards the light and small pale leaves. It is a common problem in the winter when your home remains warm due to central heating which encourages active growth at a time when there isn’t enough light to support it.

Where possible, move your plant into a lighter position. In the winter, you can encourage your plant to go into a resting phase by watering it less and keeping it in a cool spot. For more answers to houseplant questions on lighting see our Houseplant Lighting Guide.

Why have are the leaves of my houseplant gone brown at the edges?

Houseplant with brown leaf margins

Image: Thompson & Morgan

If just the edges or tips of the leaves have gone brown, this is normally a problem with dry air or draughts. Move your plants away from radiators and mist them regularly or stand them on a bed of pebbles in a tray full of water.

Also check for any watering issues. See Overwatering or Underwatering below.

Why is my houseplant suddenly dropping leaves?

Person shovelling up leaves which have dropped from Ficus benjamina plant

Ficus benjamina can sometimes drop their leaves
Image: Ficus benjamina from Thompson & Morgan

This quite often happens when you bring a new houseplant home or when you move a plant from one room to another. Ficus benjamina are especially prone to leaf drop.

It indicates a sudden change of conditions, the most common being variations in watering, light and temperature.

Overwatering or Underwatering

Firstly, check the potting compost and if necessary, tip the root ball out of its pot to have a good look at it. Feel the compost and assess the moisture level. If the root ball is soggy then you have overwatered, it. Quickly remedy this by standing the bare root ball on some newspapers. Keep refreshing the damp newspaper until the root ball has sufficiently dried out. Unfortunately, overwatering can cause irreversible damage. In future, avoid leaving your plant to sit in water. Take care to ease off watering during the winter months when the plant is not actively growing.

If the root ball is very dry it may be that you have underwatered it. Try to maintain a consistent level of water during the growing season whilst allowing the top few centimetres of compost to dry out between waterings.

Changes in Light

Too little light can cause the lower leaves to drop and is a common cause of leaf drop in Ficus benjamina. Try to provide as much light for your plant as possible, particularly during the winter. For more answers to houseplant questions on lighting, see our Houseplant Lighting Guide.

Changes in Temperature

A change in position, room, seasons or temperature can cause leaf drop. This frequently happens with new plants which have transferred from a warm and humid greenhouse environment to a cool, dry home. Other stressors include turning on the heating in winter, placing plants near radiators or in drafts.

Try to find a position for your houseplants where the environment is consistent. Newly bought plants may take a while to acclimatise and should gradually recover by themselves providing their other needs are met.

Why has my succulent/cacti gone rotten at the base and keeled over?

Rotten cactus in a pot

Image: Shutterstock

This is normally caused by overwatering. Unfortunately, it indicates that the roots have rotten and the damage is irreversible. However, with succulents you may be able to trim the stem back to healthy material and repot it to grow new roots.

Vine weevil grub

Vine weevil grub
Image from Thompson & Morgan

Another frequent cause of this problem with succulents is vine weevil grubs – particularly if you have left your plants to stand outside in the summer months and then brought them back under cover for the winter. These grubs eat all the roots leaving a hollow stem and the whole rosette becomes detached from the soil. When you remove the rosette, you should be able to spot C shaped, creamy bugs about 10mm long with brown heads. As above, trim off all the dead and damaged parts and a few of the leaves so you have enough of a stem to re-anchor the plant and pot it up into a new container. The rosette will grow new roots. If vine weevil is a frequent problem, avoid the use of pesticides and treat your plants with biological nematodes which parasitise the vine weevil grubs.

We hope we have answered your houseplant questions, if you would like more information on houseplant care, view our other Houseplant Blogs.

To find the perfect houseplant for your space, and plenty of top growing advice, head over to our houseplant hub page.

 

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