Pinching a plant is a method of pruning back growth to achieve some other more desirable end, such as bushier branching-out, additional flowering or strengthening a main stem instead of allowing side shoots to grow. Pinching back can be accomplished as simply as it sounds, by literally pinching off the unwanted shoot between the fingernails of your thumb and forefinger. Narrow pruners or pointed scissors can also be used to pinch back your plants.
Pinch back mum plants early in the season, when they are about 6 inches tall, by removing between 1/2 inch and 1 inch of the end of each stem with your fingers or small scissors, cutting back to just above where a leaf meets the stem. Side branches will form at each spot where you pinched the mum stems. When these side stems get to be about 6 inches long, pinch each of them back, too, to make your mums extra bushy and produce more flowers, advises the Purdue Extension. Asters, phlox, sedum, artemesia and veronica can also be pinched back like mums for denser blooms, suggests the University of Illinois Extension.
Annual Flowers and Houseplants
Many types of annual flowers as well as houseplants grown for foliage will benefit from being pinched back to encourage full growth of side-shoots. For example, pinching back the main tips of grandiflora and multiflora petunias when they are about 6 inches high encourages side-shoots and more blooms, according to the University of Minnesota Extension. Promptly pinch off dead flowers along with the stem beneath them down to the next leaf juncture on most annuals to encourage prompt re-blooming. Leggy houseplants such as philodendrons benefit from pinching back the emerging tips of new growth at the end of long stems to encourage side branches to fill in.
Pinching a tomato plant means the opposite of pinching back most flowering plants. Instead of pinching back the main stem to force side-shoots and make the plant bushier, pinch out the side-shoots to encourage stronger growth of the main stem. This will encourage larger, earlier fruit, according to the East Texas Gardening experts at Texas A&M University. You can also pinch back new growth on the main stem after it has set four clumps of flowers, so that the plant puts its energy into growing and ripening tomatoes rather than new vegetative growth.
Pinching back herb plants such as basil, thyme and sage makes the plants grow more thickly, and also gives you a harvest of the most flavorful new growth tips for use in cooking. Follow the plant's natural shape when deciding how far back to pinch the stems, advises the Herb Companion. Pinch off all the flower heads if the herb plant has started flowering, and take each stem back to just above a spot where leaves are attached. Some herb stems get woody, so using a small pair of sharp scissors rather than your fingertips can be helpful. Pinching back half of a clump of lavender or bee balm before flowering will also spread the blooms over a longer period of time.
- Purdue Extension; Pinch Your Mums; B. Rosie Lerner; June 2, 2005
- University of Illinois Extension; Pinching and Pruning--A Perennial Primer; Sandra Mason; April 27, 2006
- University of Minnesota Extension; Growing Petunias; Deborah Brown; 2001
- East Texas Gardening: Tomatoes Til Frost
- Herb Companion: The Art of Pinching; Barbara Pleasant; June/July 2004
- Photo Credit Martin Poole/Digital Vision/Getty Images
How to Pinch Back Plants to Make Them Branch Out
Pruning plants keeps them tidy, promotes good air circulation to mitigate disease, provides cuttings to propagate more plants and makes some plants...