When you are at a garden barbecue you might have a guest ask you if you pinch your sunflowers. So, we need to talk about it.
Most plant growers at some point in their horticultural careers have “pinched” back or removed flowers from marigolds or zinnias and other ornamental species. Likewise, they may have cut a branch or stem from a tree or bush. The result was new growth on the plant where the old plant part was removed.
The idea of pinching sunflower is to promote more and longer branches producing a fuller plant. Branches will grow from the leaf axils below the point of the pinching when pinching is done early.
For several reasons, any similarity to other ornamental species ends with the broad concept of pinching sunflower. First, sunflower pretty much is programmed to flower during the first three weeks of plant growth after emergence from the soil. Pinching will force more branches and retard flowering by a few days when done early, but very few sunflower varieties will initiate new growth once the plant has started to flower and flowers begin to senesce.
Secondly, not all sunflower varieties will respond to early growth pinching. At SunflowerSelections.com we have grouped our sunflowers by stem type. Those that we have selected for branching are more likely to respond to pinching if you want to try it.
Those that we indicate are single stem likely will respond very little to pinching. Genetically they are not programmed to branch even if you try to force the issue on them.
We know that from experience you have to pinch the growing point of a branching sunflower plant early if want to see a beneficial result. Hopefully you have planned to pinch and given your plant plenty of space to develop those branches that you will force develop.
Remember, branching varieties will branch. You don’t have to pinch them. However, if you want to influence the shape of the plant and the length of the branches by pinching, we recommend that you pinch the plants when there are 4-5 sets of true leaves. Using your fingernails, pinch into the growing point of the plant and remove the tip as shown in the photos below.
Branching sunflower at proper stage for pinching.
Growing tip at pinching. Well before flower bud formation.
Growing tip of sunflower immediately after pinching.
