This is perhaps the question we get asked more often than any other single question at the nursery, so we thought we’d try to explain….
Dead or Alive?
It’s sometimes hard to know!
Well of course if you look closely you’ll see that the Clematis in the picture is well and truly alive, but hampered by a lot of dead looking growth. Clematis are without doubt one of the UK’s most popular climbing plants, and with a tiny amount of know how, it’s so easy to know how to look after each type. So here goes….
The early ones
We call them ‘Group 1’
OK, so there’s a little bit of science, I promise it won’t be super-boring.
Group 1 Clematis always flower at the beginning of the year. These clever little sausages make all of their flowers, inside the stems of the plant, the preceding Summer. They’ll get their flowering out of the way in April & May, they’ll have a little rest to recover themselves, and then they’ll work hard to produce their flowers before Winter comes. You can’t see them but I promise you, they are there, sitting in the wings, waiting to wow you when they emerge in the Spring.
If you can remember that, then common sense will tell you how to prune them. If you prune them in the Winter, and you prune hard, you’ll have a lovely Clematis the following year that is, well, very very green. No flowers….because you’ve chopped them all off!
If you prune it in August or September, because it’s got too big and you really can’t deal with it, guess what….you’ll get hardly any flower next year because you’re pruning it a the precise time its beavering away to make them all.
If you prune in Spring, it’s the same as pruning in the Winter….bye bye lovely flowers.
So, there’s one time to do it, without compromising your display for the following year…..PRUNE STRAIGHT AFTER FLOWERING.
That way, as the plant recovers from pruning by producing new shoots, it’s still got all Summer to work on producing new flowers too. Does that make sense?
We should add that if you’re happy with the size of the plant and it’s not outgrown its’ stay, you do not need to prune it. Plants don’t get pruned in the wild, after all. It’s a great way to control the size of your plants when gardening in a confined space, but it’s not essential, especially if it’s a youngster and you actually want it to gain in size.
That’s Group 1’s….prune immediately after flowering, as hard as you like, if you need to.
The ‘Dinner Plates’
We call them Group 2’s
Now these are the Clematis everyone knows and loves as traditional Clematis. The flowers can be enormous. They can be double or single. And they normally flower between mid May and late June, although that’s not set in stone.
Group 2’s are very much like Group 1’s, in that they produce their main crop of flowers for May/June, the preceding season. So in lots of ways, they are very much the same as Group 1’s….prune them hard in Winter or Spring, and you’ll end up with lovely, healthy green plants, with almost no flower.
For this reason, the advice is pretty much the same….PRUNE IMMEDIATELY AFTER FLOWERING.
There are a couple of subtle differences though. Whereas Group 1’s you can pretty much prune as hard or as soft as you like, we do recommend always pruning a Group 2 back to around waist height, give or take.
Why? Well, couple of reasons for this. Since they don’t have the enormous vigour of some of the Group 1’s, waist height gives the plant a good chance to produce ample growth the following year so that when it flowers, those lovely flowers are positioned in a perfect position for you to enjoy them….at around 4-8 feet. Any taller and you won’t appreciate them….let alone the leafless twigs at eye level, needed to transport water to the flowers doing their thing above your head….they’ll be topheavy and ugly.
When pruning to waist height, also take out any really small, thin, weedy stems….the more you prune out weak growth, the more the plant will respond by producing strong growth instead.
The other lovely lovely thing about Group 2’s, is that after your waist-high pruning, your plants will most likely reward you with a second flush of Summer flowers. Now they won’t be big dinner plates, and if you’re growing older double varieties, they’ll most likely just be single, but flowers are flowers, right? They will enhance your walls and trellis beautifully, as a ‘thank you’ for looking after them!
Which leaves one group left….
The late Summer ones
We love them to bits!
Now you don’t need to be a super duper detective to know that these are called the Group 3’s! And they work quite differently from the Group 1’s and 2’s.
Why? Easy….they do everything in a single season. No forming flower buds the previous year. They’re the sprinters of the Clematis world and they want to grow quickly, before they give you a jaw dropping late display of flowers.
What that means is that they start into growth in Spring, grow nice and fast with long supple stems, to gain as much height as they can before they erupt into flower in mid-late Summer. If you’ve never grown these before, give one a go. It’ll add yet another season to your early and mid season Clematis and be flowering into August and September without question!
They also happen to be the easy peasy ones to prune. You just grab them by the scruff of the neck in January or early February, and cut THE WHOLE PLANT back to about 6 inches (15cm) from the ground. Brutal, effective, and oh so satisfying! The plant will love you for it, and you’ll never be left with old, brown, dead stems which really don’t look appealing.
Easy, eh?
Pruning when planting
As a one-off….
Any plant, once planted, will benefit from pruning to some degree. Talking about this often causes frowns on otherwise happy faces, but I promise you that if you can de-stress a plant in it’s first few weeks after planting, the long term success of that plant is pretty much guaranteed.
What do you think is the most stressful time in a plants’ growing year? Well, it’s when the plant is trying to provide as much water and nutrition as it can…..and that’s at flowering time. Ironically, that’s the time that most people buy their plants…..and its the very same time you want to minimise stress on your new purchase.
The easiest way to do this…. and please don’t hate me…..is to chop all the flowers off when you plant it. In fact the easiest thing to do, is to chop the whole plant back to around 12 inches (30cm) to allow if to settle down, recover, and most importantly, recover with renewed vigour, more shoots, and a much better chance of success. The flowers you’ll lose in year 1, will be repaid indefinitely in all of it’s future years. And clematis will give you 20 years of joy if they like where they are…often far longer!
So, prune it confidently at planting time, and while we’re talking about planting, you can plant it deep. Look at the picture above, and you’ll see it’s being planted perhaps 4-6 inches (10-15cm) deeper than it was in the pot. As far as planting like this goes, Clematis really are the exception; we wouldn’t recommend this with any other plant.
You see, they like their roots cool, and deep planting helps. As long as the soil at the bottom of the planting hold is well dug over and not compacted, those big golden bootlace roots will venture down to the cool soil, and keep the plant very very happy.
It’s also said that deep planting helps avoid the dreaded Clematis Wilt disease, although contrary to popular belief, it’s really only the Group 2’s which suffer from this, neither Group 1 or 3 Clematis are susceptible. So deep planting is a great idea for the big flowered Group 2’s, it’s not quite as important for the others.
I hope this helps make it a little simpler. Try to hold on to your plant labels in a safe place so if you’re not sure which one you’ve got, you have a record somewhere at home. And if you lose your labels, don’t fret….you can easily determine which group you have, by the time of year that it flowers.