By Jan Phipps
The gardening methods of pinching and deadheading sound a little mean, don’t they? But while they sound a little harsh, both methods can greatly improve a plant’s appearance.
And, if you’ve always thought deadheading and pinching describe the same thing, you’re not alone. Pinching removes the growing tip of the plant to encourage it to branch out and become bushier. Deadheading is removing spent blooms to tidy up the plant’s appearance.
Pinching is usually done when a plant is first transplanted, often before any buds appear. It is also done on fall-blooming plants in late June to keep them from becoming too long and leggy by the end of summer.
So why does this method work? Many annuals and perennials contain a hormone called auxin, which is stored at the top of the stem. Its purpose is to make the plant grow tall and straight with a single main stem. When you pinch off the top half-inch, the auxin is removed, which allows side branches to develop.
Pinching is easy and kind of fun if you don’t mind green fingertips. Simply use your thumb and forefinger to “pinch” off the growth from the top inch right above a pair of leaves. If you’re not a green-fingernail sort of person, just wear gloves or use hand pruners.
Deadheading not only makes the plant look better, but it encourages it to bloom again. Flowers past their glory quickly become unattractive, so removing their dead blooms is probably something most people already do to tidy up a bit. Why does this make the plant re-bloom? Seeds are produced in the flower head, but when they are removed from the plant, it’s tricked into producing more in its relentless quest to propagate.
There are times when deadheading all the blooms is not a good idea. If your garden is visible from inside the house, it is nice to have something out there for winter interest. Plants with stiff stems and large seed heads provide just that, along with some food for the birds. Coneflowers and black-eyed Susans are two examples of plants you might not want to deadhead.
Another reason to leave at least a few spent blooms is when you want a plant to self-seed for next year. In Illinois, some great self-seeders are morning glory, hollyhocks, money plant, rose campion and dill. For the more tender annuals, whose seeds can’t survive our winters, you will have to save them yourself.
The perennials that benefit from more radical pinching (pruning, actually) in early summer are mums, asters and some of the bigger sedums. All of these plants split and fall over once the buds open in the fall unless they’ve been helped to stay shorter and bushier. So, get out in that garden and have at it!