Pruning Sedge
When and how — Carex morrowii
Prune your sedge in March — the optimal month is usually March.
The next pruning window is March next year.
When to prune?
The ornamental grass sedge is pruned in March.
Cut ornamental grasses once a year, at exactly the right moment.
Ornamental grasses split into two groups with very different needs. Warm-season grasses (Miscanthus, Panicum, Pennisetum) die back above ground over winter and are cut down to about a fist's height in February or March. Those dry stems provide winter interest and protect the crown from frost and rain. Cool-season grasses (Stipa, Carex, Festuca, Deschampsia) stay green or semi-evergreen and must NOT be cut back hard — a spring tidy where you comb out the old dead blades with gloved hands is enough. Hard-prune a Stipa and whole tufts can rot out and die.
How to prune sedge
Carex morrowii is evergreen and requires very little pruning compared to deciduous grasses. The main task is a light tidy-up in March, just before new growth begins in earnest. This timing allows you to remove any winter-damaged or tatty foliage without cutting into fresh spring growth, and the plant quickly fills out again as temperatures rise. Use your hands or a pair of garden gloves to comb through the clump, pulling out any dead, brown, or damaged leaves. These usually come away easily. If there are stubborn dead leaves tangled in the centre, use a pair of sharp secateurs or garden scissors to snip them out at the base. Avoid cutting into the crown or removing too much green foliage, as this sedge relies on its evergreen leaves year-round. You're aiming to refresh the plant, not cut it back hard. Unlike many ornamental grasses that benefit from being cut to the ground annually, Carex morrowii should never be sheared right back. Its evergreen nature means it continues photosynthesising through winter, and severe pruning can weaken or even kill the plant. If your sedge has become congested or the centre has died back after several years, the better approach is to lift and divide the clump in spring rather than prune it. Simply tease apart sections with roots attached and replant the healthiest outer portions, discarding the tired centre.
Common mistakes
✗ Cutting warm-season grasses down in October
You lose the winter silhouette AND the crown drowns without the protective dry stems. Wait until late February or early March, just before new growth starts.
✗ Hard-cutting cool-season grasses
Species like Stipa tenuissima and Festuca tolerate it poorly and may rot out. Combing with gloves is the right approach.
Too late this year? Here's what to do
Better to wait than prune at the wrong moment. The next optimal window is March next year. Until then: leave the plant alone — only remove dead or diseased wood (which you can do year-round).
