How to grow petunias from seed

Petunia ‘Mirage White’ F1 Hybrid from Thompson & Morgan

Grow your own stunning petunias from seed this year
Image: Petunia ‘Mirage White’ F1 Hybrid from Thompson & Morgan

There’s a real sense of satisfaction in growing your own show-stopping display of petunias from seed. And the good news is that sowing petunia seeds isn’t difficult at all. Follow the advice from T&M’s petunia expert, Kris Collins, and produce a bumper supply of strong and healthy seedlings. Here’s our quick and easy guide to germinating petunia seeds.


How to get the most from your petunias

Petunia ‘Pegasus Wine Splash’ from Thompson & Morgan

Petunia ‘Pegasus Wine Splash’ petals are attractively flecked with burgundy
Image: Petunia ‘Pegasus Wine Splash’ from Thompson & Morgan

Petunias are hugely popular bedding plants that you can order as plugs or garden-ready plants. Alternatively, you can sow your own petunia seeds as a cost-effective way to replenish hanging baskets and fill your garden with colour. 

Here, T&M’s resident expert, Kris Collins, shares a few simple tips to increase the flower power and longevity of your petunias. 

Why grow petunias?

Petunia 'Frills & Spills™ Susanna' from Thompson & Morgan

Buy scented petunias to add an extra dimension to your displays
Image: Petunia ‘Frills & Spills™ Susanna’ from Thompson & Morgan

Petunias are something I turn to every spring in order to get my garden ready for summer. I couldn’t be without them in my hanging baskets. Trailing types, covered in masses of fragrant trumpet blooms, such as Petunia ‘Easy Wave Ultimate Mixed’, are perfect for lending that luxurious feel to your summer garden.

Most commonly used in container displays, there are actually many varieties that work well in border plantings too. Prolific growth smothers weeds and traps moisture in the soil, whilst also providing a carpet of colour.

Petunias require very little specialist upkeep. As long as you’re prepared to water regularly and remove spent flowers as they go over, you’ll be in for a season of scent and colour right through to autumn.

Which petunia should I choose for my space?

Petunia ‘Back to Black’ from Thompson & Morgan

Petunia ‘Back to Black’ produces gorgeous velvety black flowers
Image: Petunia ‘Back to Black’ from Thompson & Morgan

When it comes to choosing your petunias, firstly consider where you want to grow them. Grandiflora types, like Petunia grandiflora ‘Cascade Pink Orchid Mist’ F1 Hybrid, are best saved for basket and container displays – the large blooms are better shown off at height, and will be less prone to weather damage and mud splash.

For a show-stopping petunia bedding display, multiflora types including Petunia ‘Frenzy Mixed’ are the best option. They have smaller flowers and more of them, creating a carpet of colour that will shrug off a summer shower.

How often should I water my petunias?

Petunia 'Surfinia' Collection from T&M

Keep hanging baskets out of direct sun to reduce water loss
Image: Petunia ‘Surfinia’ Collection from T&M

Watering is very important for healthy petunias. In the height of summer you may need to water containers and baskets twice a day, but at least every other day in an average British summer.

For those that work long hours and have less time for watering, it’s a good idea to move petunia hanging baskets and small containers to a shady spot during heatwave conditions, keeping them out of the afternoon sun until you can get home to give them a drink.

Alternatively invest in an auto watering system to reduce your workload and keep your baskets evenly moist.

Do petunias need deadheading?

Petunia ‘Trailing Surfinia White’ from T&M

Keep petunias blooming by removing wilting flower heads 
Image: Petunia ‘Trailing Surfinia White’ from T&M

Remove spent flowers as often as possible. Don’t just clear away the spent petals, but make sure to remove the entire flower head otherwise seed pods will form, the plant will think it has achieved its objective, and flowering will start to reduce.

Should I feed my petunias?

Petunia ‘Trailing Surfinia Purple’ from T&M

Petunia ‘Trailing Surfinia Purple’ produces electric flowers and long trailing stems
Image: Petunia ‘Trailing Surfinia Purple’ from T&M

Feed your petunias using a specialist petunia fertiliser for the best results. Add the fertiliser to the compost mix before planting containers and baskets and it will feed your plants for the whole season.

We’ve seen some excellent results with petunias in our technical trials for Incredibloom. Our one-off granular feed, applied at planting time to soils or composts, encourages up to 400% more blooms and provides everything your plants need for up to 7 months – covering the whole growing season.

Can I train my petunias?

Petunia 'Trailing Surfinia Blue' from Thompson & Morgan

Train your petunias by pinching out young growing tips
Image: Petunia ‘Trailing Surfinia Blue’ from Thompson & Morgan

Pinch out the growing tips of your plants during the early stages of growth, and do this two or three times before planting out to encourage side shooting. This will lead to much more compact plants with many more flowers.

By mid-August, some petunia varieties may start to look a little tired and straggly. To encourage a second strong flush of blooms to last well into autumn, cut the whole display back by a third and offer a general purpose liquid feed. Within a week or so the plants will start to bush out again and fresh new flowers will soon follow. Within 2 weeks, just in time for your August Bank Holiday garden parties, the display will again be in full bloom with no sign that it has been pruned.

If you’re growing your petunias from seed, aim to sow plants 10-12 weeks ahead of safe planting. So if you’re generally safe to start planting out bedding plants in your area from the 1st week of June, aim to sow your seeds in the first week of March. I’ll be looking at sowing petunias in more detail before then, so stay tuned!

We hope you’ve enjoyed this post and found our top tips helpful! If you think we’ve missed anything let us know! For even more info, visit our petunias hub page for lots more resources to help you grow and care for petunias.

Hanging basket habits revealed

Nurserymans Choice Hanging Basket Mixed Collection from T&M

A vibrant display of hanging baskets can make your garden in summer pop!
Image: Nurserymans Choice Hanging Basket Mixed Collection from T&M

A recent Thompson & Morgan survey has revealed some surprising habits, when it comes to summer hanging baskets.

Love them or loathe them, nothing sets up the garden for summer like a vibrant display of hanging baskets. Thompson & Morgan, the UK’s leading mail order supplier of seasonal basket plants, asked the nation’s gardeners how they use hanging baskets to best effect. The findings were most interesting…


Suffolk train stations back in bloom

Ipswich Station Thompson Morgan, ActivLives' gardeners and Jackie Station Manager at Ipswich

The T&M team, ActivLives’ gardeners and station manager Jackie at Ipswich Train Station

Colour has returned to Ipswich and Stowmarket train stations thanks to a partnership between train operator Abellio Greater Anglia, local seed and plant specialist Thompson & Morgan and Ipswich-based charity ActivLives.

In a repeat of last year’s amazing hanging basket displays, volunteers and young learners from ActivLives have been busy growing baskets of Thompson & Morgans’ best selling Begonia ‘Apricot Shades’. This year they’ve added Begonia ‘Fragrant Falls’ to the mix, to provide scent as well as colour to the platforms.

Begonia 'Fragrant Falls' & Begonia 'Fragrant Falls' at Ipswich Station

Begonia ‘Fragrant Falls’ & Begonia ‘Apricot Shades’ from T&M at Ipswich Station

Not only will the baskets brighten up the journeys of everyone who passes through the stations on the London to Norwich mainline, the project has provided local young people with valuable horticultural experience. Participants from a number of organisations, including WS Training, Talent Match and Seetec, take part in training programmes at ActivLives’ two garden projects in Ipswich to gain skills for work.

The ActivLives team planted up the baskets back in April. They have since tended the Begonia blooms at the glasshouses in the walled garden at Chantry Park, bringing them into peak condition for display at the train stations.

Ipswich Station Thompson Morgan with ActivLives' gardeners

Ipswich Train Station with Thompson & Morgan Blooms

Thompson & Morgan’s Horticultural Director, Paul Hansord said:

“We were pleased with last year’s baskets, but ActivLives has outperformed themselves this year, with bigger and better baskets for real impact. Planted in incredicompost® and fed with incredbloom® at planting time, these baskets look stunning and will continue to perform right through to autumn. Requiring minimal care from station staff – spent flowers simply fall off to be replaced by fresh new blooms. The addition of Begonia ‘Fragrant Falls’ should really lift the spirits of workers on their daily commute and provide a warm welcome for visitors and tourists passing through both stations.”

For help and information on growing and caring for your own begonias, visit our begonias hub page for a wealth of resources.

Getting the best from your fuchsias – our growing secrets revealed

Fuchsia ‘Dollar Princess’ from T&M

Fuchsias need some attention to ensure they stay blooming all summer long
Image: Fuchsia ‘Dollar Princess’ from Thompson & Morgan

Fuchsias require very little care to put on a fantastic show, but for the best displays it pays to learn a few simple tricks and tips. Take a quick look at the T&M horticultural team’s trade secrets, and make sure your favourite fuchsia plants look their best all summer long.

Best growing conditions for fuchsias

Fuchsia ‘Delta’s Sarah’ (hardy) from T&M

The unusual blue flowers of ‘Delta’s Sarah’ increase each year given the right conditions
Image: Fuchsia ‘Delta’s Sarah’ (hardy) from Thompson & Morgan

For a fantastic fuchsia display this summer, here’s how to get the conditions right:

  • Plant in fertile, moist, but well-drained soil, with shelter from cold, drying winds. Ahead of planting, work plenty of rotted compost or manure into the area with some slow release fertiliser.
  • In patio containers and window boxes use a 50:50 mix of multipurpose compost and soil-based John Innes No.2 compost. Again, add some slow release fertiliser ahead of planting.
  • In hanging baskets, stick to multipurpose compost to keep the weight down, but add some Swell Gel to reduce watering needs in the height of summer.

Best places to plant different types of fuchsia

Fuchsia ‘Sparkling Giant’ Collection

Trailing fuchsias are perfect for hanging baskets and window boxes
Image: Fuchsia ‘Sparkling Giant’ Collection from Thompson & Morgan

Depending on the type of fuchsia you prefer, follow the ‘right plant in the right place’ rule to get the most from these elegant blooms:

  • Use hardy fuchsia varieties for permanent planting – use as specimen shrubs or seasonal floral hedging.
  • Use trailing fuchsia varieties in baskets and containers at height or as seasonal ground cover.
  • Use upright fuchsia varieties in patio containers and window boxes or as gap fillers in the border.

How to grow on fuchsia plug plants

Fuchsia ‘Elma’ (hardy) standard from T&M

Train a fuchsia into a standard or buy one that’s been started for you
Image: Fuchsia ‘Elma’ (hardy) standard from Thompson & Morgan

Young fuchsias are frost-tender and need to be grown on in warm, frost-free conditions before planting out at the end of May or early June. As soon as your plug plants arrive, pot them on into small pots or cell trays filled with multipurpose compost and wait until it’s warm enough to plant them out.

Early training:

  • Pinch out the soft stem tips once the plugs have put on three leaf sets – simply remove the tip and top pair of leaves with scissors, snips or fingers. This encourages bushier, compact plants and more flowers.
  • Pinch out 2 or 3 more times once each of the resulting side shoots has developed three pairs of leaves – the first flowers will start to bloom 5-8 weeks after the last pinching.

Later training:

  • The early training above will create a bush.
  • You could experiment and create a fan or espalier, similar to fruit tree training. This is best done with hardy varieties and done over several years to create a truly impressive flowering wall shrub.
  • It’s easy to train a standard fuchsia (long bare stem with a lollipop canopy), but it can take 18 months to achieve. For more in-depth instructions, see our full article on growing a fuchsia standard.

On-going maintenance:

  • Feeding: Fresh compost should supply enough nutrients for 4-6 weeks of growth. Start to offer a balanced liquid feed after this time, once or twice a month through the season. Alternatively, for fuss-free feeding with impressive results, mix our long lasting Incredibloom® plant food with your compost at planting time for 7 months of controlled feeding.
  • Watering: Keep compost and soil moist at all times. In the height of summer, baskets and small containers may need watering twice daily – do this early morning and late evening to avoid scorching the foliage.
  • Deadheading: Look for faded blooms every time you go past your plants – the more you remove, the more your plants will bloom.

Try a little tenderness!

Fuchsia aborescens from Thompson & Morgan

This tender fuchsia bears large panicles of scented pink flowers, followed by purple fruits
Image: Fuchsia aborescens from Thompson & Morgan

While there are some fantastic hardy fuchsias available it’s usually the tender varieties that provide the most impressive floral displays. You can overwinter container plants in a frost-free location for re-using the following year – but you might not need to! Tender varieties are getting tougher and tougher and you may find they’ll survive winter in your garden soil with little to no protection.

Experiment this year with one of your favourite plants – leave it in place at the end of the season, cutting it back by a third and mulching around the base. With luck you’ll be rewarded with re-growth next spring. If not, you can always reorder fresh plug plants in spring for guaranteed success next summer. If you’re looking for more help with growing and caring for your fuchsias, there are links to plenty of handy resources on our fuchsias hub page.

Author: Kris Collins


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