How to grow clematis – 5 things you need to know for stunning climbing displays every year

Gardeners learn how to grow clematis for a reason: it grows quickly, it’s easy to care for, and it flowers prolifically.

It's actually one of the best fast-growing plants you can grow for privacy – it’ll cover a trellis or obelisk in no time at all, producing tons and tons of attractive blooms in an array of shapes and colours.

I’ve thrown together a guide on how to grow clematis, with planting, feeding and pruning tips from the experts, to help you establish the climber in your garden.

What you'll need

1. Planting

Clematis is vigorous. It’ll spread at speed, which is great news if you’re looking for garden screening ideas – but you’ll need to bear its ultimate size in mind when it comes to planting. Clematis montana 'Mayleen', which you can buy at Thompson & Morgan, is actually known as 'mile-a-minute clematis' because it grows so fast – but it's also scented, and one of the most beautiful.

Clematis is a climber, so you’ll need to plant it next to a support of some kind. My mum used a slinky to grow her clematis (the results were amazing), but you could also buy an obelisk, like this twin pack of decorative obelisks from Argos. Or, simply grow it next to a wall or fence.

‘Position clematis 30 to 45cm away from the base of the wall or fence, so that the roots will be kept clear of the rain shadow, so they can access sufficient moisture,’ says Lucie Bradley, gardening and greenhouse expert at Easy Garden Irrigation.

If your wall or fence doesn’t already have one, Lucie says you should attach a trellis or wire so the clematis can climb.

'Plant clematis in a sunny position, as they flower poorly in shade, but keep their roots cool and shaded with tiles, stones, or similar mulching materials,' adds Annelise Brilli, Thompson & Morgan's horticultural expert. 'You can also plant shallow-rooted perennials or bedding plants around them.'

2. Watering

Clematis are thirsty plants, too – and according to Lucie, they’ll need even more water during their first two years of establishment.

‘It’s best to deep water clematis so that the ground is thoroughly wet up to about 30cm deep,’ Lucie says.

There’s always the question of whether you should water your garden in the morning or at night, and when it comes to clematis, Lucie backs one timeframe in particular.

‘Water early in the morning, using a watering can or hosepipe to direct the water to the base of the plant without wetting the foliage,’ she advises.

3. Feeding

Since clematis is a flowering plant, it’ll need plenty of nutrition to keep its displays looking their best. You can actually buy clematis-specific fertilisers, like Vitax Clematis Feed, from Amazon.

The first form of feeding comes during planting – Lucie says it’s best to prepare the ground with organic matter like well-rotted manure or compost before planting. You could even add fertiliser, like Envii Climbers Biofertiliser from Amazon, to the planting hole to encourage stronger, healthier roots.

Lucie recommends mulching around the base of the plant every spring, and then feeding the plant with a balanced fertiliser every three months.

‘To attain the best blooms, use a fertiliser high in potassium – such as a tomato feed – just before they are due to flower, as this encourages bud formation and results in richer, more vibrant colours when the blooms open,’ says Lucie. Levington Tomorite, which you can also order from Amazon, is a popular choice.

4. Pruning and training

There isn’t really a straightforward answer when it comes to the best time to prune clematis – it depends on the type of clematis you have, and it’ll fall under one of three clematis pruning groups.

Your plant’s flowering period will give you a good idea of which pruning group it belongs to – some flower during the summer, for example, while others flower during the winter.

Clematis does an easy job of training itself along a wire or trellis, but it's best to have supports in place from the very beginning.

'Erect supports before planting your clematis,' advises Annelise from Thompson & Morgan. 'Though the old brown stems look spindly and unremarkable, they soon produce vigorous shoots that need prompt tying in.'

FAQs

It's also worth learning how to grow jasmine, if scented climbing plants are your thing.