Clematis is a beautiful addition to most any space, growing up mailboxes, trellises, gutters, telephone poles, fences, boxwoods, and roses. It’s a flowering vine that is easy to grow, super showy, and requires little to no maintenance from the gardener. If you want to grow it, but are finding the instructions confusing, start here to learn how to grow clematis and, most especially, how to prune it.
But for fun, let’s start with the pronunciation of the word… Even Merriam Webster can’t decide!
Choosing Your Clematis
Like hydrangeas, knowing which clematis you have is key to taking care of them. Clematis are divided into three groups, based primarily on bloom time, so if you plan on mixing your clematis, choose from the same grouping. That allows for easier pruning.
If you know the name of your clematis, but don’t know which of the three groups it’s in (and therefore, when it’s expected to bloom), click here to find yours. If you’re already growing clematis and you don’t know its name, watch for a couple of seasons to see when your clematis vines bloom—that’s a tell-all.
BUT, don’t allow this grouping concept to overwhelm you. It’s no different than understanding that most spring-flowering shrubs bloom on old wood (azaleas, rhododendron, weigela) and summer shrubs bloom on new wood (hydrangea limelight) and so forth. To keep it simple, watch to see if most of the new growth is on last year’s vine. If so, prune it lightly and shape. If most of the new growth comes from the bottom of the plant, you can cut it back to 12″ to 18″.
Clematis Groupings
Clematis are grouped by number (1, 2, 3) or letter (A, B, C) and pruned according to type. This is the biggest thing the gardener needs to understand, and to know which group their clematis vine is in.
Clematis armandii
Group One: Blooms in early spring on old wood (last season’s wood). These are generally the armandii, montana, and alpina varieties. Typically, they require damaged stem removal or thinning every few years, and that’s it. If your clematis is blooming in early spring, you should prune it right after blooming, so you do not lose your blooms for next season.
Clematis ‘Nelly Moser’
Group Two: Generally blooms in late spring, on old AND new wood. These are the ‘Nelly Moser,’ ‘Henyrii,’ and other large-flowered clematis. You want to prune them in late winter or early spring when the buds begin to swell. Cut just above the buds.
Clematis ‘Jackmanii’
Group Three: Blooms in late summer and only on new wood. ‘Jackmanii,’ shown above, is unusual in that it flowers on both old and new wood, putting it in groups two and three. This means you can prune it lightly right after blooming, and prune it to the ground for rejuvenation every few years. When pruning it hard in the fall or early winter, expect its blooms to be reduced until the plant has time to reestablish.
‘Duchess of Albany’ is an example of a pure Group Three clematis, and therefore can be cut to the ground in spring, where it’ll sprout back from the crown.
When you purchase your clematis, the tag should tell you which group your flowering vine is in. If it does not, keep the tag for identification and check this list so you know how to prune it.
If you need (or want) a refresher on pruning these beauties, here are step-by-step instructions.
Make sure you give your clematis a trellis, fence or wire cage so it can climb.
You’ll Need a Trellis or a Supportive Shrub
Who doesn’t need a little support? Clematis use their leaf stems to climb, and these stems coil around the nearest object, just like pea vines do. But the leaf stems are short, so they can only wrap around something up to 1/4″ wide.
If clematis stems can’t find anything to grow onto, the end stops growing and dies back. If your clematis has gotten bushy and top-heavy, tie up those stems in early spring, as clematis vines are brittle and break easily. Use a wire mesh to aid in climbing when placed near a mailbox, pole, and fence. You can also use a simple trellis to lean against walls or stick into your containers.
Shrubs such as boxwoods are an excellent way to provide support, too, especially for clematis in Group Three (which grows on new wood). Why? When it’s time to prune the boxwoods, it’s time to cut the clematis back to 12″ to 18″ as well. The dark green of the boxwoods also makes a lovely backdrop for the bright flowers of the clematis. Or mix them in with climbing roses for a show-stopping scene.
Planting a ground cover like this sedum, or other perennials or shrubs will help to keep the roots of your clematis cool.
Planting Clematis
- Put them in a sunny to part-shady location, although most clematis flower more prolifically in full sun.
- Plant with the roots of your clematis in a cool, shady spot (the shade of nearby shrubs does the job nicely), or if that isn’t possible, be sure to mulch the roots well to help keep them cool.
- The soil should drain well as clematis do not like wet feet.
- Clematis do not want to be moved, so think of this spot as permanent.
- Use a balanced fertilizer (10-10-10) once monthly during the growing season.
Clematis ‘Guernsey Cream’
Clematis may be the show-off of the garden, but it doesn’t ask for much in return. With just a little understanding of its bloom group and a supportive place to climb, this flowering vine will reward you with a stunning display year after year after year. Don’t let the pruning guidelines intimidate you; once you know when your clematis blooms, the rest is simple. Whether it’s winding up a trellis, mingling with roses, or adding a surprise pop of color to a mailbox post, clematis is a reliable, low-maintenance companion for any sunny to part-shady spot. So plant one, give it a place to climb, and let it do what it does best: put on a show.
