Reinvigorate flowered perennials
Cut back clumps of spring-flowering perennials to encourage a fresh flush of foliage.
Cut back Euphorbias
Euphorbias look a lot better if spent flowers are removed, cutting the flowered stems back to ground level. This can be especially important with Euphorbia amygdaloides var. robbiae, as old stems are prone to powdery mildew.
Perennials that are showing new shoots from the crown can still be propagated via basal stem cuttings.
Take cuttings from Dianthus
Take cuttings from garden pinks (Dianthus). They can be pulled off the parent plant while holding a suitable non-flowering shoot four pairs of leaves from the tip. Treat as softwood cuttings.