Disturbing or damaging roots will slow down growth until the plant recovers and could be fatal. The answer depends on how close the seedlings are and how big they are. The closer and bigger, the more entangled the roots will be. If you want to take the risk, on a cloudy day dig up the entire clump and move to where it is shaded. If the roots don't easily separate, abandon the attempt. And don't try to get every last one separate; it is just too risky. Seedlings that were separated off need to go back into pots and pampered until they show signs of growth. Keep them out of the sun. Because of the time needed to recover from root damage, you may find starting again from seed produces a mature plant almost as quickly.
Answered on May 24, 2018
Was this answer useful?00
Looking for more?
here are more questions about...Cosmos Flowers