Another hot, dry month has spoilt many summer plants, but it has suited plants like lavender which has been covered in flowers. (I was pleased to see a hummingbird hawk-moth feeding on mine.) But now that the flowers have faded it is time to cut it back to prevent it becoming untidy and woody. Trim with shears but not down into the bare wood as it may not shoot again. I always leave a few flowers on a plant to set seed as I like to sow some each year for new plants to replace ones that are getting past their best. I grow two compact varieties, Hidcote, a dark purple and Munstead which is a shade lighter.
Although lots of plants need cutting down for the winter, penstemons don’t as they are quite tender and the old foliage protects new growth over the winter. Cut these down at the end of March. Dahlias are in full flower now and need dead-heading to help them continue flowering, not just cutting off the dead head but back to the base of the stem, like roses. To distinguish between the old and new buds: the old ones are cone shaped and the new buds are more rounded.