There is no single annual cutback rule for everything called a geranium. First distinguish hardy Geranium perennials from tender Pelargonium plants often sold as bedding geraniums. Their growth and winter care are different, so a blanket winter pruning date can give the wrong result.
Hardy geraniums
Many summer-flowering hardy geraniums can be cut back after their main flowering flush if stems have sprawled or foliage looks tired. New foliage may follow, and some varieties flower again, but a second display is not guaranteed. Check the cultivar rather than cutting an actively flowering plant simply because a calendar says to do so.
The RHS hardy-geranium guide describes post-flowering cutback for many border varieties. Timing depends on the plant and local season; the UK months in a guide are not a universal schedule. Remove dead seasonal growth without damaging new shoots, and leave healthy foliage when no corrective work is needed.
Tender bedding and scented pelargoniums
Pelargoniums do not become frost-hardy through pruning. Decide whether you will keep a plant growing in a bright protected place, overwinter it by another suitable method or replace it next season. That decision affects pruning time.
The RHS pelargonium guide distinguishes autumn cutback for some overwintering arrangements from spring pruning of plants kept actively growing. Avoid treating every pelargonium as a dormant outdoor perennial. In a frost-free climate, care should follow its actual growth rather than an assumed winter shutdown.
What can be removed as needed?
Remove dead or damaged material and spent flowers where appropriate. Use clean, sharp tools and avoid tearing stems. For shaping a healthy pelargonium, prune to suitable growth points rather than shearing blindly into old growth. Do not prescribe one-third off every plant regardless of species, condition or season.
If foliage is yellowing or growth is weak, check light, root condition and watering before assuming pruning is the cure. Heavy cutting does not correct waterlogged roots or inadequate light, and a stressed plant may not replace lost foliage readily.
Can the prunings become new plants?
Healthy pelargonium shoots can be used for cuttings under suitable conditions. Hardy geraniums have different propagation options, often including division depending on the species. Do not use diseased material or assume every geranium roots from an identical stem cutting.
The useful annual routine is to identify the plant, inspect its growth and choose the right seasonal care. Pruning is a tool for a particular need, not an obligation to remove healthy foliage once every year.
