Pinching is an exhilarating pastime, but often depending on whether you are the pincher or the pinchee. In the latter case, males often get a slap upside the head if their pinching is indiscreet, or even if it isn’t. On the other hand, pinching can have a marvelous effect on your garden if practiced in timely and knowledgeable fashion. ( I better get to the point here before I get into trouble.)
A lot of perennials, and even some annuals and shrubs, are the better for a good satisfying pinch from you, the pincher. It must be done correctly and at the right time.
Take the tall summer phlox, which is the backbone of our, and perhaps your, summer garden. In a wet spring and early summer, these can easily grow to a prodigious height before blooming in July or August. Then they will put on large heavy panicles of flowers that can cause the whole tower to topple over just at a critical time in the life of your bed or border.
To prevent such an event, timely pinching of the stems before bloom will cause secondary branching and even more flowering, albeit in smaller panicles. Between the reduction in size of the stalks and the dwarfing effect of the pinching on the flower heads, the proclivity to topple is prevented.
One problem with this practice, if indeed it is a problem, is somewhat later flowering, though not as much later as one might imagine.
I have described before my practice on phlox pinching to both delay and extend flowering. Say you have an established clump of tall phlox (or other late summer flowering plant, for that matter) that you feel is going to get too tall. About mid-May your first pinch is in order. This is for the front part of the clump only and takes off about half of the height of the stems. The back side is left unpinched and will flower earlier. Just following the flowering of the back half, it is deadheaded (in effect, pinched), just as the forward plants are coming into bloom to continue the show. This can, in a good season, be repeated in reverse order and this will keep the flowering going even longer. I have had summer phlox in good blooming fettle right up to frost some years.
Let us take a look now at an example of pinching, or cutting back, a shrub for similar result. The hardwooded, mostly white, hydrangeas of the paniculata species, flower on young wood of the year. If, when the stems elongate in late spring, they are pinched back about halfway into new wood, the flowering will be somewhat delayed, but the additional stems produced by the pinching, will produce more, but smaller, panicles of flowers.
One of these, relatively new on the market, is the variety ‘Phantom,’ which produces large white panicles of flowers in about July most years. I set one of them a few weeks ago. It was robust, but somewhat small. I pinched back each stem, which seemed like a shame, but I know (hope) it will put out numerous flowers the first year on each branch. There are numerous other varieties now that can be treated the same way.
Many annuals are better for pinching, for the same reasons. In fact, some annuals can be pinched immediately following setting. The pinch will do them a world of good, as it will to you, when they produce more flowers.
From Poor Willie’s Almanack — Pinch away, but be careful.
JIMMY WILLIAMS is the garden writer for The Post-Intelligencer, where he can be contacted on Monday mornings at 642-1162.