IN THIS GUIDE
Agapanthus are tender perennials that need protection over the winter months but can be grown in many UK gardens.
They are often grown in containers so they can easily be moved undercover for the coldest months, though they can also be grown in a border in southern, warm, sunny and protected gardens.
If you are growing Agapanthus, you might wonder if you should prune your plants. And, if you do, when and how you should do so.
Here’s the usual process to follow:
- Determine whether you need to prune at all by determining if you have a deciduous or evergreen type.
- Decide whether you will cut back deciduous Agapanthus in autumn or spring.
- Cut back deciduous Agapanthus to around 10cm above the soil surface
- Leave evergreen agapanthus alone, or give it a trim for aesthetic reasons if you wish.
When to Prune Agapanthus
Agapanthus of the types which are pruned are usually pruned or cut back in October, or in March.
Whether you prune in autumn or spring will largely depend on personal preference.
Do You Need to Cut Back Agapanthus?
Whether or not you should prune Agapanthus at all depends on whether you are growing a deciduous or evergreen type.
Deciduous types are usually cut back hard, but evergreen types are usually left alone, unless you wish to give them a little tidy up for aesthetic reasons.
Identifying Whether You Have a Deciduous or Evergreen Type
Deciduous Agapanthus are those which die back over winter. Evergreens will keep their foliage year-round.
Deciduous Agapanthus tend to be hardier than the evergreen types.
Deciduous types are sometimes overwintered outdoors with a thick mulch of straw or autumn leaves to protect the crown, while evergreen types are almost invariably moved undercover for the winter months.
Pruning Deciduous Agapanthus
If you have a deciduous agapanthus that you plan to keep outdoors over the winter months, then it is usual to cut back the stalks with spent flowers or seed heads (if these have not already been deadheaded) to around 10cm above the ground.
However, you might also choose to leave seed heads in place, since these can be rather attractive, and only cut the plant back to the base in spring.
However, the foliage should remain in place to offer a little extra protection for the crown over the coldest months before you cut back straggly old leaves in the early spring to make way for new growth.
If growing in a container and moving under cover over the winter, you may choose to cut the plants right back down to the crown in Autumn.
Pruning Evergreen Agapanthus
Evergreen agapanthus should usually not be pruned or cut back.
It should be left alone, aside from removing any unsightly leaves or removing particular portions of the plant with a little trim to improve its visual appearance.
A permaculture garden designer, sustainability consultant and freelance writer, Elizabeth works as an advocate for positive change. She aims to inspire others to reconnect with nature and live in a more eco-friendly way. She also tries to practice what she preaches as she tends her own forest garden, polyculture beds and polytunnel. See her personal website here.