Clematis plants are often classified in groups according to their pruning requirements. The correct time for pruning clematis depends upon the type of flowering wood that the plant produces. Some will flower on the previous year's growth while others bloom on young shoots produced in the same year.
Knowing when to prune clematis will ensure you get the best flowering possible. If you are not sure which species you are growing, but you know when the clematis is in flower, then you can normally determine what type of pruning it will require according to these clematis pruning groups.
If you're not sure what the pruning group of your clematis is, all the clematis on our website have the pruning group stated on the product page.
Group 1 includes clematis that flower in winter and spring on the previous year's growth. These include Clematis alpina, Clematis macropetala, Clematis montana and their cultivars. This group also includes evergreen Clematis.
Start pruning clematis from group 1 immediately after flowering. Remove any damaged or dead stems and reduce the remaining growth to fit the available space.
The large flowered cultivars in group 2 bear flowers on new shoots that emanate from the previous year's stems in late spring and summer. Some cultivars will produce a second flush at the tips of the current year's growth in late summer and autumn.
Prune clematis from group 2 in spring before they start into active growth. Remove any damaged or dead stems and reduce the remaining growth back to a set of strong healthy buds. New flowering stems will be produced from this framework of previous growth.
Group 3 contains the late flowering species and their cultivars that bloom from summer to late autumn on the current years stems. This group also contains the herbaceous species of clematis.
Clematis in group 3 are arguably the easiest to prune. These plants can simply be cut back to a pair of strong buds about 20cm (8”) above ground level, removing all of the previous year's growth. Prune group 3 clematis in spring before they start into active growth.