How to Trim Mum Plants for More Roundness
- 1). Monitor your mums. Wait for the growth on the stems to reach 3 to 6 inches long.
- 2). Pinch the new growth back with your thumb and forefinger to leave only three to four leaves on each stem. This allows the mums to branch out and grow bushy. Pinch back the mums all spring, through June or even July. Most mums should not be pinched after August 1, and a few should be left to grow after July 15.
- 3). Deadhead any spent flowers in late summer or early fall. Cut the spent flowers from the mums with scissors, about half way down the flower stem.
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