Answer: It sounds as though your chrysanthemums are going through some transplant shock. If there were 3 separate plants in the pot, it is possible that the roots were intertwined and when you separated them, you severed the roots. This can be stressful for plants, especially if they were flowering at the time. The best approach now is to water them deeply once or twice a week and to wait for them to recover. Even if the tops die down, the roots may still survive. If so, you'll see new shoots emerge from the plants next spring.
Hope your mums regain their health!
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