Gadenin日本語Get the appWhat pinching actually does
A young marigold grows as one leading stem because the tip releases a hormone that keeps the buds in the leaf joints below dormant. Remove the tip and that suppression stops, and the two or three pairs of side buds nearest the cut all break into growth within about a week. Each of those shoots then carries its own flowers.
The result is a shorter, wider, more stable plant with far more flowers, each slightly smaller. That trade is almost always worth taking with French and signet types, where quantity is the point. With African types grown for a few big show heads it is a real choice, because pinching gives you more heads of smaller size.
Pinch at four true leaves
The window is when the seedling has three or four pairs of true leaves and stands four to six inches (10 to 15 cm) tall, usually a week or two after potting up. Pinch earlier than that and there are not enough leaves left below to power the regrowth, so the plant sits still for a fortnight. Pinch much later and you are cutting off stem the plant has already paid for.
Take the top pair of leaves and the soft growing point between them, about half an inch to an inch (12 to 25 mm) of tissue. Pinch just above the next pair of leaves down. Use your thumbnail and finger on soft growth, or snips on anything that has gone woody. Never pinch below the second pair of true leaves, because a plant left with only its seed leaves has no engine to regrow with.
- Count the leaf pairs first Ignore the two rounded seed leaves at the bottom. Count only the divided true leaves, and pinch once you have three or four pairs of them.
- Pinch just above a leaf joint Cut a couple of millimeters above the joint, not through it. A long stub above the joint dies back and can rot down into the live stem.
- Pinch on a dry morning The wound seals over within a few hours in dry air. Pinching in wet weather leaves an open cut for gray mold, which is the one real risk in the whole operation.
- Do not water heavily afterwards The plant has just lost leaf area and is using less water. Keeping it wet for the next few days while it has no growing tip is how young plants rot at the base.
A second pinch, and when to stop
Two or three weeks after the first pinch, the side shoots will be four to six inches long. Pinching each of those tips again doubles the branch count and gives a very dense low plant. This is worth doing for containers and edging, where habit matters more than earliness, and it delays the first flower by roughly two weeks.
Stop pinching once buds are visible. From that point every tip you take is a flower you have thrown away, and the plant will branch perfectly well on its own from then on through deadheading. As a rule, do all your pinching before the plants go out, or within the first fortnight after planting.
| Timing | Action | Effect on the plant |
|---|---|---|
| 3 to 4 true leaf pairs | First pinch | Two to four main branches, first flower delayed about a week |
| 2 to 3 weeks later | Second pinch of each side shoot | Very bushy and low, first flower delayed about two more weeks |
| Buds visible | Stop pinching | Any further pinching removes flowers you have already grown |
| Midsummer | Deadhead instead | Cutting back to a leaf joint does the same job on a flowering plant |
| Late summer | Cut back by a third if leggy | One last flush of flowers before frost |
Pinching an African type is a different decision
The tall African marigolds naturally make one dominant stem with a very large terminal head and only weak side shoots. Left unpinched you get that single spectacular flower on a long stem, which is what you want for cutting. Pinched, you get five or six good heads at chest height on a self supporting plant, which is what you want in a border.
Decide before you pinch, because you cannot undo it. If you are growing them for cut flowers, leave the tip alone and instead rub out the small side buds that form around the main bud, which pushes all the plant's effort into one head. If you are growing them for display, pinch once and stake once.
Note in your records which plants you pinched, on what date, and how many flowering stems each carried by midsummer. One season of that comparison across a few plants settles the question for your conditions better than any general rule.
Rescuing a plant you did not pinch
A leggy unpinched marigold that is already three quarters of the way to flowering is not lost. Cut the whole plant back by a third, taking every stem down to just above a leaf joint, and feed nothing. It will break from those joints in about a week and flower three weeks later, bushier than it was.
The same cut works in late summer on a plant that has gone thin and woody in the middle. Marigolds respond to hard cutting back much better than most bedding annuals, because dormant buds sit at every leaf joint the whole length of the stem. The only cut that will not recover is one below the lowest leaves, into bare stem with no buds on it.