Deadheading has many benefits
Deadheading is the secret to long-lasting color and healthier plants. While deadheading may not be very enjoyable, it is an important task in maintaining a healthy well-kept garden which will reward you in the future. There are four good reasons to deadhead. First, it will prolong the bloom period of most perennials and annuals, and in some cases perennials will send up a second batch of flowers. Second, it prevents seeding of perennials from spreading. If the perennials is a hybrid, it may not reproduce the cultivar which you planted, and sometimes the new seedlings actually crowd out the parent plant. Third, preventing seeds from ripening will keep a plant stronger and healthier, because all the energy of the plant does not go into making seed, but goes back to the root system and strengthens it. And fourth, your plants will look well-groomed, rather than shaggy, brown and tattered.
Pinch or snip off individual flowers on perennials and annuals such a petunias, marigold, peonies, roses, lilies, day lilies, daisies and just about anything that blooms. In the case of geraniums, simply snap off the bloom at the bulge at the base of the stem, so you do not see the empty stem. Even hollyhocks will bloom for weeks and not look ratty if the spent seedpods a picked off and not left to turn brown.
Small flowers that bloom in clusters atop branched stems need a bit more snipping to keep them blooming and not reseeding. Examples of these are phlox and bee balm. Seeds can ripen early and drop without ever turning brown. In the case of phlox, as the main panicle withers, rather than snip individual florets or removing the entire stem, cut it back to a side shoot or branch. There are side shoots that are beginning to bud and bloom on each phlox stem. These will grow and develop, and prolong the bloom period of the plant. If the entire stem were cut down to the ground, you would lose all these flowers. If you wait until the entire stem is finished blooming, the top portion will look ugly and will have begun to drop unwanted seeds.
In the case where lots of blooms are produced over an entire plant, it would require a lot of time to remove each flower. Rather wait until the majority of flowers fade, and shear them off with a scissor. Examples would be threadleaf coreopsis and baby's breath. You can use hedge shears or a string trimmer and cut the plant to the ground, it will come back as a nice mound of foliage.
Dianthus and sweet Williams should have their flowers trimmed with a scissor but their foliage must be left or the plant will be killed. That ugly dried foliage that is left in the fall and remains next spring is from what new shoots will arise. Many a bed of dianthus or sweet Williams has been destroyed because some one wanted to tidy up that flower bed and get rid of all that dead foliage.
Some plants that are self-cleaning and do not need deadheading are angelonia, calibrachoa, dragon wing begonia, Marguerite daisy, impatients and moss rose.
Some plants benefit from a process called undercutting. Plants like bacopa, calibrachoa, lobelia, petunia, swedish ivy, and twinspur, are some plants which form a lush, thick mat of color which looks great. However as the summer moves on these form a thick web of stems that block water and sunlight from reaching the lower branches. This eventually slows the growth of the plant and sometimes kills it. You can prevent this by lifting the carpet of flowers so you can see the stems underneath that need to be undercut. To undercut use a pruner to snip stems. It doesn't matter which one you cut; the goal is to thin the mat and stimulate new growth. As you snip, pull out cut stems until the remaining ones look loosely interwoven and you can slightly see through the mat. Also check from the top to see that you are getting an even appearance.
Some foliage plants improve their appearance and become fuller and lusher if they are pinched back. If they are not cut or pinched back they become tall, leggy, and some such as coleus want to go to seed. Other plants which often benefit from being pinched back to just above a healthy set of leaves, are: browallia, dichondra, Joseph's coat, licorice plant, Persian shield and sweet potato vine.
Look at your plants and if you see spent blossoms, drying leaves or branches, or crowding, remember almost every plant will benefit from some snipping and trimming to maintain its health and good-looking appearance.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.