Pruning Catmint

Catmint flowers from early summer through to late summer, producing spikes of blue or purple blooms that are highly attractive to bees. The key to keeping it tidy and encouraging a second flush of flowers is a hard cut-back after the first flowering wave fades, typically in late June or July. Use garden shears or hedging shears to shear the whole plant back by about half, removing spent flower stems and the top growth. This prevents the plant from flopping open in the centre, promotes fresh foliage, and often triggers a second round of blooms in late summer or early autumn. In November, once flowering has finished and the foliage begins to look tatty, cut the plant back to within 5–10 cm of the ground. This autumn tidy-up prevents the old stems from becoming a soggy mess over winter and reduces the risk of fungal problems. If you garden in a very exposed or wet location, you can delay this cut until March instead, leaving the old growth as some protection for the crown over winter. In March, whether or not you pruned in autumn, tidy up any remaining dead stems and trim back to the emerging new shoots at the base. This is also the moment to remove any winter-damaged growth. Catmint responds well to this treatment and will quickly produce fresh, aromatic, grey-green foliage. The plant does not require complex pruning or shaping—just these straightforward cuts to keep it vigorous, compact, and floriferous. Always use clean, sharp tools to avoid bruising the soft stems.