Aquilegia and Digitalis should have set their seed which could be shaken around the area to produce a self-sown display for another year.
Herbaceous Geraniums which have produced their first display, can be sheared off - flowers and foliage - and will send re-growth to flower again in a few weeks.
Aubretia and White Alyssum can be cut back hard to produce compact plants for the future.
Agapanthus and Crinums respond to a liquid feed as they produce their flower spikes but both prefer a sunny, dry position.
Arum Lilies (Zantedeschia) can be kept lush and flowering over a long period by feeding and copious watering.
The same applies to taller flowering hybrids in the borders.