Answer: It may be time to dig and divide your chrysanthemums. When plants become overcrowded, the roots compete for moisture and nutrients which usually results in poor blooming. Wait until next spring when new shoots develop, then dig each plant and divide it. Every shoot should have some roots attached. Replant your divisions 12-18" apart to give each plenty of room to grow.
Just as an afterthought - you can promote larger flowers on your plants if you remove all except the center flower bud in each cluster of buds. Do this as soon as the buds begin to develop. This will redirect the plant's energy into a single flower rather than a cluster of flowers.
Best wishes with your mums!
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