How to prune long-leaved speedwell

Deadhead during flowering (summer); cut back by a third after main flush; cut to ground in late autumn. Remove individual spent flower spikes, cutting to a side shoot or healthy leaf. After peak bloom, cut the plant back by one-third to one-half using clean secateurs. Remove all top-growth in late autumn.

Deadhead regularly in summer; annual cut-back in late autumn. Long-leaved speedwell benefits from deadheading to extend summer flowering and prevent self-seeding. Cut spent spikes back to healthy leaves or side shoots. After the main flush subsides, cut stems back by a third to half to encourage compact re-growth. Cut the whole clump to ground level in late autumn.

Remove individual spent flower spikes, cutting to a side shoot or healthy leaf. After peak bloom, cut the plant back by one-third to one-half using clean secateurs. Remove all top-growth in late autumn.