From my perspective as a chrysanthemum, my primary instinct is to grow tall and reach for the sun. This is governed by a principle called apical dominance. The main, central stem (my apical meristem) produces a hormone called auxin that suppresses the growth of the lateral buds further down the stem. This ensures I put my energy into vertical growth to outcompete other plants for sunlight. While this is good for survival in the wild, it results in a tall, sometimes leggy plant with a single flower at the top in a garden setting.
When you "pinch" me, you are physically removing the tender tip of my main stem. This action is a signal to my entire system. By removing the primary source of auxin, you break the apical dominance. The hormonal suppression on my lateral buds is lifted. Suddenly, those dormant buds in the leaf axils (the points where leaves meet the stem) are activated. They receive a clear message: "The leader is gone; it's your turn to grow!" My energy, which was solely dedicated to upward growth, is now redistributed to these multiple new growth points.
The act itself is simple for you but transformative for me. Using your thumb and forefinger, you compress and remove the top inch or two of my stem, just above a set of leaves. It is crucial to make a clean pinch to avoid damaging the remaining stem tissue. Immediately after this, my internal resources—water, nutrients, and hormones—are rerouted. Instead of one dominant stem, I will now channel that energy into producing two, four, or even more new stems from the nodes below the pinch. This is the fundamental mechanism that creates a denser, bushier form.
For me, a chrysanthemum, flowers are the culmination of my growth cycle, and they form at the ends of my stems. Therefore, the number of stems directly dictates the number of flower buds. By pinching me and encouraging multiple stems, you are essentially programming me to produce a multitude of flowering sites. Each of those new lateral branches will eventually develop its own terminal bud that will become a flower. The result is a plant that is not only structurally fuller and more robust but also absolutely covered in blooms, creating the spectacular display gardeners desire.
Timing your pinches is critical for my development. This process should be done during my active vegetative growth phase in the spring and early summer. It gives the new lateral stems ample time to grow, mature, and develop their own flower buds. A common schedule is to begin pinching when I am about 6 inches tall and to repeat the process every few weeks until mid-summer. It is vital to stop pinching by a date that allows me approximately 90-100 days to grow and set buds before my expected autumn bloom period. Pinching too late would remove the very flower buds you are trying to encourage, resulting in no blooms at all.
