This generally occurs 12 to 14 days after planting. Hard pinches are not desirable because it reduces the number of breaks. A second or third pinch may be required on some cultivars. Some of the more recent cultivars are heavily self-branching and may not require additional pinches. Regardless, the last pinch should be completed between July 10 and July 25.
Late pinches can delay flowering.
See Table 3 for a typical pinching schedule. Garden mum cuttings can, at times, set flower buds prematurely under low temperatures, stress from under watering, low fertilizer levels, late application of the first pinch, or inadvertent exposure to the incorrect photoperiod. Fortunately, they can be developed into quality plants by pinching back further to remove visible buds and unseen developing buds. Cultural practices should also be altered to keep the plant actively growing with plenty of water, fertilizer, light, and space to grow. Plant Growth Regulators Plant growth rate and final height varies among garden mum cultivars.