Regular pruning of clematis helps encourage strong growth, beautiful blooms, and keeps the plant in check. If left unpruned, clematis can turn into a tangled mass of stems with a bare base and flowers well above eye level. Clematis in pruning group three bloom in late summer on growth made that season and should be pruned in late winter or early spring. This method is ideal for herbaceous clematis.
When to Prune Clematis in Group Three
Clematis in pruning group three flowers on new growth made in the current season. These plants grow from the base each year, making them suitable for hard pruning. Pruning should occur when buds show signs of growth, typically around February.
How to Prune Clematis in Group Three
Initial Pruning and Training (For Young Plants)
If young clematis plants are left unpruned, they often produce long single stems, with flowers only at the very top. To promote a strong, well-structured plant:
- In the spring after planting, prune back the young plant to just above a strong pair of buds about 30 cm (1 ft) above soil level.
- This encourages multiple stems, which can be trained into supports to give good coverage.
Pruning Established Plants
For established clematis, prune them back to the lowest pair of healthy buds, around 15-30 cm (6-12 inches) above soil level, in February or March.
- Small-flowered clematis like C. ‘Bill MacKenzie’ can be lightly thinned out, leaving attractive seedheads to be enjoyed through the season.
- Unpruned plants can become top-heavy, flowering above eye level with a bare base.
Optional Treatment
Some mid- to late summer flowering clematis can be treated as either pruning group two or group three, depending on your preference.
Herbaceous Clematis
For herbaceous clematis like C. heracleifolia or C. integrifolia, prune them back to near ground level in early spring or late autumn.
Examples of Clematis in Pruning Group Three
- ‘Abundance’ AGM
- ‘Étoile Violette’ AGM
- ‘Ernest Markham’ AGM
- ‘Lady Betty Balfour’
- ‘Polish Spirit’ AGM
- C. viticella ‘Purpurea Plena Elegans’
Pruning clematis in group three is vital for promoting healthy growth, manageable size, and abundant blooms. Regular pruning helps ensure your clematis remains a stunning, well-shaped feature in your garden.