Deadheading, Cutting Back and Deadleafing - Perennial Maintenance
Some gardeners call them deadheads and some call them mushmummies and some of you are probably wondering what Iím talking about. These terms refer to the spent or dying blooms on plants. There are few garden chores that are more satisfying or that give greater returns for the effort than the removal or pruning off of these "dead" or spent blooms. Deadheading is usually done on a regular if not daily basis from spring to frost especially if you grow perennials. More deadheading is required during hot, dry weather and less during cool, wet weather because cooler weather extends the life of blooms. New plants require little deadheading in their first year.
There are many reasons for deadheading. Some plants like peonies, coreopsis and hibiscus have unattractive deadheads. Deadheading greatly improves the look of the plants especially if the plants are close to seating areas. A perennial border that one sees from a distance can get by with less vigilance when it comes to deadheading, however the advantages from a gardenerís point of view are enormous.
Deadheading prolongs flowering by initiating a second flush of smaller and less numerous blooms. This is true of perennials such as babyís breath, delphinium, phlox, bellflower and gallardia to name just a few.
When you remove the spent blooms of plants you are helping to preserve the plantís energy. That energy goes into the producing of more blooms rather than going into seed production. It also prevents aggressive plants from reseeding at will. Seed production not only drains energy from the plant, it also causes the plantís foliage to deteriorate. Deadheading promotes root and foliage growth, which keeps the plant looking healthy.
How do you deadhead? It really depends on the plant. Look for new buds or flowers on the plant. If there are any, then prune to a sideshoot. If you cannot see any new flowers or buds, then prune to a lateral or side leaf. Perennials that fall into this category are coreopsis, heliopsis, phlox, veronica and peony to name a few.
Some plants that have a single bare stem or just a few leaves like hostas, lambís ears and coral-bells, should be cut close to the ground after flowering. I personally am not fond of the blooms of lambís ears and some hostas but I really like the foliage so I cut the blooms off as soon as they open.
Plants like balloon flower and peach-leaved bellflower require careful deadheading. This is because the new buds are beside or just below the spent blooms. If you cut the stem back to the foliage you will lose those blooms.
Some spring blooming, low growing rock garden or edging plants can be deadheaded by shearing or "cutting back." Using garden shears, cut down the plant by one half after flowering is done. This sounds rather drastic, however it will result in attractive, new growth. Often the plant will re-bloom. Some perennials like silver mound, moss phlox, and candytuft open up in the center after flowering. Shearing these plants prevents them from opening up in the center and also prevents the plants from becoming "woody".
Perennials like purple coneflower, bee balm, sedum; Siberian iris, Joe Pye weed and rudbeckia have ornamental seedheads. These not only provide interest in the garden through fall and winter, they also provide food for birds. Remove two thirds of the seedheads and leave one third on the plant. You do not want to allow too much seed formation as it can affect the vigour of the plant./P>
If all of this just sounds like more work than you are prepared to do in your garden, choose plants that require less maintenance. Astilbe, oriental poppy, russian sage, sedum, false blue indigo, liatris, pulmonaria, siberian iris, and ligularia are some perennials that do not require deadheading.
"Cutting back" refers to the removing of significant amounts of foliage and sometimes deadheads as well. It is done to extend the life of some perennials or to regenerate new growth or to limit height.
Once flowering is finished, perennials such as shasta daisies, yarrow, and delphiniums can be cut back to the newly emerging foliage at the base of the plant. This often stimulates a second bloom. If you cut some plants back by one third to one half, early in the growing season you will get shorter plants that will bloom later than usual. Some summer and fall blooming perennials to cut back before flowering to control their height are asters, purple coneflower, lavender, heliopsis, cardinal flower, bee balm, phlox, rudbeckia, and artemesia. I cut my heliopsis back by one half in mid June. It will flower at a height of three-ft. rather than five feet and the bloom time is delayed by less than two weeks. Cutting back "leggy" plants like mums or balloon flower in early June will produce shorter and stronger stems. Some people pinch off the individual flowers but I shear them off especially with mums. Itís much less work and the plants donít seem to mind.
"Deadleafing" is simply the removal of dead leaves. When leaves have yellowed or turned brown, they are removed to improve the appearance of the plant. Leaves that are damaged by insects or disease should be removed promptly to prevent the spread of disease. Dying leaves can be caused by the stress of too much or too little sun, rain, heat or humidity. Read the labels when you buy a plant. Knowing what a plantís needs are, and placing them where their needs will be met, results in a happier, healthier plant.
Deadheading, cutting back and deadleafing have many advantages for the perennial gardener, not the least of which is keeping you up close to your plants, so that you can spot minor problems before they become major ones. The greatest advantages of deadheading and cutting back however are prolonging bloom and encouraging new growth!