Cutting Back and tidying up perennial plants

CUTTING BACK PERENNIALS
As winter begins to dig deep and all around the perennial garden is bare, maybe your thoughts turn to tidying up and clearing away. Now would be a good time to cut back your herbaceous perennials, right?
Certainly you can do it over the coming weeks, if you can’t stand the sight of bare stems and brown stalks in your garden? But there are arguments for leaving it until the very end of winter, or early spring.
Firstly it is more wild-life friendly to leave old growth around. It harbours insects and seeds that provide valuable food for birds during winter, and also cover and protection. The second important consideration is plant hardiness. If you are looking at plants like some of the newer Coreopsis and Penstemons, that maybe aren’t that hardy overwinter if we get a very severe spell then the old growth provides valuable added protection and will help them come through the worst unscathed.
You might also be cultivating plants that have some benefit even whilst ‘dead’ The architectural, striking stems of Cynara cardunculus, some grasses, Rudbeckia, Phlomis, Monarda’s, Achillea and Iris foetidissima seed heads, to name but a few, have definite value in the winter garden. Would you really want to part with them so soon?
So really it’s up to you – clear away and tidy up now if you wish but consider the other side of the story too.
PRACTICAL CONSIDERATIONS
Some Perennials have very brittle stems that will come away cleanly and easily without too much of a struggle. However Daylilies, [Hemerocallis] Kniphofia, Agapanthus and some other perennials may cling on to the parent clump rather. If you tug too much you can loosen mart of the clump from the soil, or even tear it away completely. Be prepared to cut such stems manually with a sharp pair of secateurs. The stems should be removed cleanly as close to the base of the plant as possible. Make sure at the same time as clearing old and dead growth that you remove all old leav and leafmould/detritus as it may harbour diseases.
If you are cutting back slightly less hardy perennials now, as discussed above, then if you can provide a mulch around the crown of the plant then this will help replace the insulating effect of the growth you have just taken away.