Answer: You can prune in the spring so the tree has all summer to develop new growth which will have time to harden off before cold weather arrives. If you prune in late summer or fall, any new growth it develops won't have time to mature and can suffer from winter kill. Eucalyptus usually responds well to spring pruning. The rule of thumb is to remove no more than one-third of any live growth during any one pruning session.
Best wishes with your Silver Dollar trees!
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