Farmers Weekly Review

Why is it that come late June, some of our plants, particularly our annual plants, are not looking like the tight, full of color they did when you bought them in early May? They may look like they are yawning, all sprawled out with long stems and few flowers.
Did you know there is a pinch for that?
Pinching back some of our plants (emphasis on SOME, not all) is a great way to get the most production out of many flowers, herbs and even some vegetables. So, just what does this term “pinching back” mean? Pinching is actually a form of pruning. But not that once-a-year pruning we do to trees, but an ongoing practice to help plants develop a fuller shape and more robust bloom and growth.
You probably already have been pinching one plant and you may not even realize it — the fall-blooming mum. Those large, round, brightly colored mums don’t start out that way. If we don’t continually pinch back our mums until the end of June, we would end up with a straggly, somewhat gawky tall plant with just a few blooms.
It is the pinching, or cutting back of the mum, that makes it branch out more. You don’t know it, but at the end of each branch of a plant, whether it is a chrysanthemum or a spruce tree, there are plant hormones at the tip that are kind of a “king of the hill.” These hormones prevent other side branches from, well, branching out.
And when the tip of that plant is pruned out, the side branches rejoice that their dominating king is gone, and they send out new side branches. I am sure you have seen this phenomenon on evergreens done by Mother Nature. Have you ever seen a Christmas tree that doesn’t have one branch at the top, but two? Or more? That happens when naturally a single stem at the top is damaged or broken from wind or ice.
The side branches just under the top stem now are in their own race to become top stem, all growing upward. Until one eventually takes dominance and starts producing the hormone that pushes the other branches back into submission.
So why is pinching good for many plants? New side branches will eventually make for new flowers. Or in the case of herbs, more leaves to harvest. Pinching helps to keep these plants in their best physical shape, too. That basket of petunias will stay in that tight ball instead of having bad hair straggly stems.
So how and when do you pinch plants? And just what plants is this appropriate for and, more importantly, which ones should never be pinched?
You don’t need any special tools to pinch, just a nice sharp thumbnail. Pinching is on soft growth. So, to know where to pinch, look at the stems of your plants and since it is still early, you can look to pinch back 1 to 2 inches. Look at each stem like it is its own little tree, go backwards from the tip and as close to the next branches (nodes where the leaves come out), pinch there.
Once this pinching is done and that apical (top) hormone is removed, new little branches just under the remaining leaves will start to branch out. Plants like petunias, marigolds, verbena, coleus, salvia and snapdragons all benefit from pinching early in the season just after transplanting.
Many gardeners look on in horror as I am just pinching off almost all of the flowers of the new plants I purchased. But a little tough love now will give me much longer production throughout the entire growing season.
You might not know it, but greenhouses where our annuals are grown are pinching back all the time. Who would want to buy a straggly petunia or a marigold without flowers? They don’t pinch back physically like we do at home, but rather chemically. That is how we get those full-bloom, picture-perfect plants we buy in spring.
Pinching is also done to encourage more bloom. Plants are on a mission. All plants try to make more of their own kind. That is how we get seeds. But once some plants set seeds and those seeds mature, they start shutting down for the season. And they quit putting a focus on making more buds and blooms.
So deadheading, a form of pinching off spent blossoms, especially on our annual flowers, will insure a constant supply of blooms. Zinnias particularly benefit from deadheading.
We also deadhead vegetables when we harvest. Did you ever notice, the more you pick, the more you get? It is true, we are removing the immature seeds (hidden in the fruit), so the plant continues to grow more.
But not all annuals benefit from us pinching off the tips. Those that grow only one central stem like campanula, celosia, cockscomb, delphinium, dill, stock, larkspur, and most sunflowers, should not be pinched back.
I am often asked about whether tomatoes benefit from pinching side shoots. This one is a little tricky, only the indeterminate varieties do. Indeterminate varieties are those that grow on and on all season long like many of the cherry tomatoes.
Determinate tomatoes, those that form a bush, then fruit, should not be pruned. These are the more modern varieties like Early Girl, Better Boy and Celebrity.

Note: There is no need to prune determinate tomato plants (bush style like Early Girl, Better Boy, etc.) Tomato pruning is only for those tomatoes that are indeterminate-those that keep on growing a long vine throughout the season (some cherry tomatoes and heirlooms).