Clematis

Clematis are extremely popular climbing vines and for good reason. Vigorous growth and spectacular flower displays. They attach themselves by means of twining leaf stalks, so are perfectly suited to grow on walls, trellises and covering old tree stumps.

Planting

There are a few important things to know before you start to grow your own clematis.

Location

If you have a sunny or part-sunny location, then you have a perfect spot to grow any variety of clematis. But, if you have a shady location, consider a spring-blooming variety for better blooming.

Support

Your vine will need some support to grown on, so plant it next to a trellis, tree trunk or open framework. In perfect conditions a clematis’ roots should be shaded and cool while its top growth is in full sun. You can do this by planting it behind other shrubs or by planting bedding plants in front of your clematis.

Soil

Clematis need rich, loose, fast draining soil to grow their best. Where soils are strongly acidic add lime, and if your soil is neutral or alkaline add bone meal.

Depth

When planting your clematis, the crown (base of the plant) should be planted 15cm below ground level. This ensures that you have multiple rooted stems on your plant, should anything happen to one vine there will be lots more coming up from the base to compensate. Only bury stems that are ripe (woody, brown, and hard). If the plant is young and the wood is not ripe enough, the hole should still be dug deep enough to bury the crown by 15cm. As the wood hardens through the summer months, the hole can be filled in.

Feeding

In February or early March, well-rotted manure or well-rotted compost makes an ideal feeding mulch. The mulch should be placed on the soil to a depth of 8cm (3”) and diameter of 50cm (20”). Never place any of the manure or compost on the main stem or leaves of the plant as this will cause damage. Liquid fertilizer is an alternative to manure and compost, just make sure to use a well-balance general feed. This can be applied during watering from April until the end of July. It is important to stop fertilizing before flowering starts. If you fertilize your plant while it’s flowering, the flowers will mature faster, and the show will be over too soon.

Pruning

In the first winter after planting a new clematis, right before the spring growth starts, all clematis types should be pruned back to three sets of leaves. This gives you a nice bushy plant in the future.

There are three main types of clematis that need different pruning. When planting a new clematis make sure to check which pruning group it belongs to, and if you’re not sure, please ask one of our knowledgeable nursery staff members.

EARLY BLOOMERS - GROUP A

These clematis flower on old wood, as in the previous season’s growth, so should not be pruned unless necessary. They bloom in the spring on vines formed last year, so if you prune any later then June (or do a severe cut back) you will be cutting off potential flowers. If you need to prune for some reason then do it immediately after blooming.

MID-SEASON BLOOMERS - GROUP B

These clematis bloom on both old and new wood, the previous season and the current season’s growth. Pruning on these varieties is optional. However, if they are frozen back to the ground they will bloom later in the season than they would have, had they not been pruned. This is true for all clematis in this section with the exception of double flowering varieties, which have an indefinite number of petals giving it an unusually full look. These will only have double flowers on old, hardened wood (previous season’s growth). Also these double flowering varieties can lack some of the vigour and free-flowering attributes that the singles have. So there are benefits to both types.

LATE-SEASON BLOOMERS - GROUP C

These clematis bloom on wood grown and hardened during the current season. They should be pruned hard during dormancy, down to three pairs of leaves on each stem. If they’re not pruned they will still bloom. However, all the flowers will appear above last season’s growth so your clematis can look quite top-heavy. A good option is to prune half the plant back, which will give you a nice tall plant but with blooms on both top and bottom.

Click here to download a printable PDF.

Favorites

The following clematis varieties come highly recommended by our nursery staff members.

Clematis ‘Blue Ravine’
A popular introduction from the UBC Botanical Garden that features soft-violet coloured flowers with contrasting darker veins. Flowering starts in May or June and lasts into September. On average it can grows 20-25cm (8-10”) a year, reaching a mature height of  2-2.5m (6-9 feet). Plant in full or partial sun. A great clematis for containers and good for cut flowers.

Clematis ’Jackmanii’
Quite possibly the most popular clematis of all time. Easy to grow, with gorgeous displays of deep purple 10-14cm (4-6”) flowers. Flowering starts in mid-June and lasts through to August. Growing from 3.5-6m (12-20’), it can grow in full-sun, part-sun or even shade.

Clematis ’Nelly Moser’
For over 100 years ‘Nelly Moser’ has been a coveted clematis. The large 18-23cm (7-9”) flowers are a pastel mauve-pink with a distinctive carmine bar running down each petal. Flowers appear in May or June and last until September. Growing up to 2.5-3.5m (8-12’) tall, it likes partial sun to shade.

Clematis ‘The President’
One of the most reliable choices, it has been popular in gardens for over 100 years! With large, 15-20cm (6-8”), purple-blue flowers that don’t fade in the sun, this a great ground cover or a climber for arbors, fences or entwined into tall shrubs. Flowers appear in May and last into September. Growing 2-3m (6-10’) tall, plant it in full sun.

Clematis ’Ville de Lyon’
A favourite since the turn of the century. The flowers have a carmine edge that fades into a lighter “throat” with large yellow stamens. These unique blooms are small, 10-15cm (4-6”) if pruned hard or larger, 12-18cm (5-7”) if pruned lightly. Flowering starts in June and lasts through to September. Growing 2.5-3.5m (8-12’) tall, plant it in full or part sun. A great clematis for containers and good for cut flowers.

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