How to prune corn mint

Midsummer and again in early autumn; cut back dead stems to the ground in late autumn or early spring. Use scissors or shears to cut all stems back to 2–3 inches above soil level. This removes old, flowering stems and triggers a flush of fresh, more aromatic foliage. Remove spent flower spikes promptly to reduce self-seeding.

Two to three times during the growing season; cut to ground level in late autumn. Corn mint is a vigorous spreader that benefits from regular cutting back to keep it in bounds and productive. Cut plants back hard to a few inches above the soil once or twice during the growing season and again in autumn. Containment (growing in pots or buried barriers) is as important as pruning for controlling spread.

Use scissors or shears to cut all stems back to 2–3 inches above soil level. This removes old, flowering stems and triggers a flush of fresh, more aromatic foliage. Remove spent flower spikes promptly to reduce self-seeding.