Mine left over two weeks ago. I think they leave when some internal signal tells them too. I had plenty of food left over for them and they just "left".
Our weird weather may be confusing some however. But today it was really cold...so depending on where you are, yours may leave soon.
They can have 2 broods per season. If this second brood was late, then they may be ready to leave now.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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