Snipping off spent flowers, stalks and all, is simple and rewarding; dahlias, roses, tender container plants and herbaceous perennials that have finished, such as delphiniums and lupins, all benefit. They look better and turn their energies towards more flowers instead of seeds. Many will flower on and on until autumn frosts. Don’t deadhead if seeds are wanted.
If you have not already done so, prune early flowering shrubs including weigela and philadelphus. Typically, one shoot in three should be removed to near-ground level. Alternatively, cut out shoots that have flowered. This is quicker and easier, but does not have the graceful effect of thinning shoots.
However, time is pressing: the older shoots need some summer weeks to mature so they carry abundant flowers next year.
Spare summer-flowering shrubs, such as hibiscus, hydrangeas and lavatera until early next spring. They need to build their resources so that when they are cut back in spring, they can send out very strong shoots that will bear flowers.
Shear off lavender flowers and 25mm of new growth once flowering is over. Having said that, if possible, leave some unpruned, because the bushes are used by birds for shelter. You can always prune in next spring, although summer pruning is preferred by most gardeners.
