Salvias are amongst the most rewarding plants I grow and some the easiest to propagate. Having amassed a collection over the years, I’ve been busy taking cuttings of my half hardy species as an insurance against any winter losses and to rejunvenate old plants. They root very easily – so do have a go and build up your own collection of these fabulous, long-flowering perennials.
Why grow half-hardy Salvias?
The first time I saw Salvias I was instantly hooked. Their flowers are distinctly lustrous and jewel-like, due to the tiny, light-reflecting hairs which cover their surfaces. This lends them an extraordinary depth of colour and they excel in velvety purples, indigo and maroons. If you prefer cooler colours, there are plenty of worthwhile choices, such as the new introduction, ‘Pink Amistad’. The range of colours and habits makes them versatile plants, suitable for everything from cottage borders to tropical schemes, and they are excellent in containers too.
Salvias are also some of the longest flowering plants I have in my garden. Keep them well fed, watered and regularly deadheaded, and many will bloom from June/July until the first frosts. Once established, they are drought tolerant and flourish on freely draining soils, although in a very hot, dry summer they will cease flowering earlier. In which case, trim them, give them a good water and wait for a second flowering in late summer.
Added to all these excellent attributes, Salvia flowers are loved by pollinating insects. Every summer I keep a keen eye on my Salvia ‘Royal Bumble’ whose sweet nectar is a favourite tipple for visiting hummingbird hawk moths. On sunny days, this day-flying moth whizzes around the garden, stopping to hover in front of the flowers, sipping the nectar with a long proboscis just like a hummingbird.
If all of this isn’t enough, Salvias also have fragrant foliage, with some, such as Salvia ‘Cerro Potosi’, being deliciously fruity.
When I first began gardening, half-hardy salvias were rather unusual and considered a little difficult due to their tender nature. There are now a plethora of cultivars available and given sunny, well-drained soil, I have found that many of these will reliably over-winter. Salvia ‘Amistad’ will even successfully overwinter outdoors in my clay soil. However, some are short-lived and like ‘Amistad’ become woody and decline as they get older. Don’t be too quick to throw them out though – Salvias are slow into growth and can look a bit sorry for themselves in the spring. Be patient and wait until the weather warms up to start them into growth.
Leave shrubby salvias with their top growth over the winter as this will give them some protection. When they begin shooting in spring, prune them back to a low framework. I normally find that the thicker stems of Salvia ‘Amistad’ die completely – in which case just cut them right down and new growth will emerge from the base.
The most tender species will need to be over-wintered in a greenhouse. They’re good candidates for patio containers, which can be easily moved under cover at the end of the winter.
How to take Salvia cuttings
- Regular pinching out of shoots from spring onwards will generate plenty of material for cuttings
- Avoid additional fertilising in an attempt to stimulate new growth for cuttings. This results in soft, nitrogenous shoots which do not root as well.
- Cuttings should be ‘turgid’ when they are taken – in other words, the plants cells are fully swollen with water. Try to take them first thing in the morning, preferably on a dull day. Water them well the day before if they showing any signs of water stress.
Harvesting cutting material
- Avoid soft tip growth – it wilts quickly, doesn’t root readily and produces weak plants.
- Avoid thin, weak growth and older, woody growth
- Select strong, actively-growing shoots which are still flexible but will snap when bent sharply.
- Look for non-flowering side shoots. If this isn’t possible, always remove the flower buds.
- When you are harvesting cutting material, cut just above a leaf node. This will leave the original plant tidy without any stubs which will die back. The material should have at least two leaf joints and be longer than the final cutting, which will be trimmed back just before insertion.
- Immediately place the cuttings in a plastic bag with a label
- Ideally trim and pot up cuttings straight away. If there is a delay, they can be stored in the refrigerator for a couple of hours. Chilling cutting material assists its survival and rooting success.
Inserting cuttings & aftercare
- Prepare pots of compost with a freely draining medium – I recommend a 50:50 mix of perlite and peat free compost.
- Trim the cuttings with a sharp knife or secateurs just below a node. The cutting can be anything from 5cm-10cm long and should have two or more leaf joints or nodes.
- Remove the leaves from the bottom of the cutting.
- Salvias don’t require rooting hormones as they root very easily
- Insert several cuttings into each pot, label and date them
- Water them well
- Place the cuttings inside a clear, polythene bag
- Put the cutting somewhere in good light in a cool environment – not in direct sun or a hot, greenhouse. Adequate shading is essential during summer.
- Check the cuttings regularly for moisture levels and to remove any dead leaves. Ventilate them if fungal growth is occurring.
- Cuttings should root in 3-4 weeks.
- When they are well rooted transfer them into individual pots with good quality peat-free compost. Grow on in frost-free conditions over winter, ready for planting out next spring.
Taking cuttings of salvias will rejuvenate your stocks with young vigorous plants and because they root so easily you’ll have plenty to give to friends too. Kickstart your collection by browsing our salvia plants online.