Knowing what to do with clematis in June can be a game-changer in your climbing plant. Get the care right this month, and you’ll be rewarded with bigger and better blooms and a generally healthier plant.
Even if you are already familiar with the basics of growing a clematis, these garden jobs to do in June are essential when it comes to ensuring a healthy and vigorous plant. ‘June is a really important month for clematis as many varieties are either coming into flower, finishing their first flush or putting on lots of fresh, new growth,’ says Richard Barker at LBS Horticulture. ‘In June, focus on making sure your clematis has plenty of light; that their roots are kept cool and moist; that they receive consistent watering and that they have good support. The flowering of the plant will almost always suffer if one of those things is missed.’
1. Keep watered
Warm weather and prolonged dry spells are the enemy of clematis in June. So regularly watering a clematis in hot weather and throughout the rest of the summer is essential.
‘If there’s one thing I’d tell gardeners in June, it’s don’t let your clematis dry out. They’re thirsty plants and can struggle if the soil becomes too dry, particularly during periods of warm weather. Regular watering will help keep the plant healthy and encourage stronger growth and more blooms,’ says Dobbies’ plant buyer, Nigel Lawton.
Watering is especially important for potted clematis in June. ‘Most varieties of clematis are happy in containers, especially more compact varieties. However, because plants in pots dry out quickly, check container-grown clematis regularly and water whenever the compost begins to dry out, this may be needed daily during warmer spells,’ says Paul Parker, CEO of plants and perennials specialists at J. Parker’s.
‘Regardless of whether you’re growing in a pot or the ground, during a heatwave, a good tip is to soak the soil around your climber as well as watering at the base, enough for water to reach the deeper roots.’ Watering too sparingly is one of the most common watering mistakes, especially in hot weather.
2. Mulch
Tied into the importance of watering is mulching. Laying a fine layer of bark mulch – like this from Amazon – around the base of the clematis in June will reduce evaporation and help the soil retain water.
‘For the best results, think about creating the conditions clematis enjoy in nature – cool, moist roots and plenty of sunlight on the stems and flowers. Mulching around the base is a great tool in achieving this,’ says Nigel Lawton, plant buyer at Dobbies.
3. Feed your clematis
In June, clematis will be working overtime, creating beautiful blooms and putting on plenty of new growth. ‘Their vigorous growth makes them incredibly hungry plants, especially in the summer months. In June, feed clematis plants every one to two weeks using a high potash fertiliser to achieve the best flowering displays,’ says Paul Parker, CEO of plants and perennials specialists J. Parker’s.
However, Julian Palphramand, Head of Plants at British Garden Centres, urges restraint. ‘If the plant is growing well, a light feed can help it carry on flowering, but don’t go overboard. Too much fertiliser, especially anything high in nitrogen, tends to give you lots of leafy growth and fewer flowers. It’s also worth checking that the stems are properly supported and gently tying in any growth.’
Vitax stocks a variety of specialist Clematis feeds, including this concentrated fertiliser, available on Amazon. Bronte also offers a lower-maintenance slow-release fertiliser, also on Amazon, ideal for those who struggle to maintain a regular plant feeding schedule.
3. Deadhead and lightly prune to encourage more blooms
Knowing how to prune clematis is one of the main challenges of growing this beautiful plant. There are three different types of clematis, each with its own pruning schedule. If your clematis falls into type one or two, then it is one of the plants you should prune in June.
Group one plants don’t need pruning, but this clematis will still benefit from deadheading.
‘For a group 2 clematis, which includes many of the large-flowered varieties that bloom in May and June, then you can lightly prune it after the first flush of flowers has faded, but don’t cut it back hard,’ advises Richard Barker at LBS Horticulture.
Instead, deadhead the spent flowers for a second bloom. ‘To do this remove the spent flowers and trim back to a strong pair of buds or a healthy side shoot just below the faded bloom. This helps tidy up the plant and can encourage fresh growth and a second flush later in summer,’ advises Richard.
You shouldn’t prune group three clematis in June; these are some of the best plants to prune in January.
4. Tie back before stems harden
Clematis are vigorous climbers, especially in June, so keeping on top of these fastest-growing climbing plants is essential.
‘Clematis can grow very quickly at this time of year, but the stems are delicate and can snap off easily in any wind. To help prevent this, use some soft garden twine and tie stems loosely to one of the best plant supports, spreading them out rather than letting everything bunch together,’ says Nigel Lawton, plant buyer at Dobbies.
This soft bio-stretch twine, from Amazon, would be ideal for securely tying the stems in without damaging them.
‘Tying in the new growth gives the plant much better coverage and protection, improves airflow, and helps you get flowers across the whole support rather than just at the top,’ explains Nigel.
Tying in the growth in June, when the stems are new and more malleable, is also much easier than when they have hardened and become woody later in the season. ‘A neglected clematis can quickly become a tangled mass of stems, whereas regular tying in will help create a much neater display and ensure flowers are spread evenly across the plant,’ adds Richard Barker at LBS Horticulture.
5. Pest control
You should always keep a weather eye out for pests or problems, but June is a good time to be extra vigilant.
‘Check for any issues such as sudden collapsing stems, pest infestations, slugs and snails. If you do notice anything, then make sure to remove any dead, damaged or diseased growth and keep the area around the base clear to maintain good airflow,’ says Richard Barker at LBS Horticulture.
Aphids are a particular problem and will destroy buds and new shoots if kept unchecked. Thankfully, a simple soapy water spray is one of the easiest ways to get rid of aphids and is very effective. Alternatively, you could use ladybirds to control aphids.
Add to basket
Amazon
RocketGro Organic Magic Mulch
This mulch has rave reviews on Amazon, and impressed our Senior Digital Editor Jenny, when she used the Rocket Gro Mulch on her garden earlier this summer
Amazon
Divchi Steel Garden Obelisk Climbing Plant Support 1.9m
Try growing any potted clematis plants up an obelisk for a striking display around a front door or on a patio.
Niwaki
Niwaki Sentei Secateurs
Make pruning and deadheading a delight rather than a chore with these goregeous secateurs.
If you care for your clematis well now, you should be rewarded with another flush of blooms and strong growth over the summer.
Read the full article here