Nearly impossible to kill a plant by deadheading
Summer jams bring up images of bright jars of berries and fruits shimmering in the sunlight. Or a summer jam can also be a musical session where musicians play, or "jam" by improvising. And of course America’s first big jam band was The Grateful Dead, whose followers soon became known as “deadheads.”
In the garden, a deadhead isn’t a band but a process. Since every flowering plant's goal is to set seed, you can keep the flowers coming by preventing seed formation. If you can “deadhead” or trim off the dead flower heads your plants will put out even more flowers in an effort to form seeds. Some plants such as snapdragons will stop blooming completely if they aren’t deadheaded.
As a rule, try to remove the old flower head by pinching off the stem just beneath the dead flower.
Different plant forms need different approaches to deadheading. Tall flowers with single slender stems should be cut off right at the base of the plant.
Bushy plants with many flowers can be cut back with hedge clippers. Some plants such as roses can be individually cut back as each blossom dies. Plants with brown or dying foliage can be cut back by one-third after they have stopped blooming. This will usually encourage the plants to send up a new flush of fresh foliage and flowers.
Plants grown for foliage such as Pulmonaria, hosta, euphorbia, and heuchera can benefit from having all flowers cut off as soon as they form.
Some begonias are self-cleaning, which means they naturally drop their dead flowers and continue blooming, so they don’t need to be deadheaded. Other plants “bury their dead” by covering old dead flowers with new ones. By observing the garden you can learn which flowers respond to deadheading.
Always give your plants a good soaking and fresh fertilizer after deadheading. Use a good organic fertilizer such as fish emulsion.
Plants react differently to deadheading, depending on the weather, the plant variety, and even rainfall. Luckily, most plants can survive even a drastic cutback without harm.
Think of any mistakes as simply a bad haircut. It is almost impossible to kill a plant by deadheading.
Even if your plants don’t rebloom, deadheading will at least keep your garden tidy.
Even herbs that begin to bloom, such as basil, oregano, lemon balm, sage, mint, and rosemary all benefit from deadheading. You can cut the herb plants back and hang the cuttings in bundles to dry or freeze them for future use.
There are some plants that you may not want to cut back at all. Hydrangea blossoms ripen into papery bronze and purple everlasting flowers as they dry out. Milkweed pods can add interest to the winter garden. Many roses form rose fruits or “hips” that linger into winter providing food for birds. Or you can use those same rose hips to make jam, for your own jam session, whether you are a “dead head” or not.