TOM KAN PA wrote:

Zone 5/6, Western Pa.. I've started tomatoes, moonflowers, pumpkins and castor
plants from seeds. They are no longer under the grow light. They all have their
second leaves.
I have them on a cart, push 'em out on the deck around noon, bring 'em in the
evening. My question.........what would be the lowest nighttime temperature
that I could leave them outside?

Frost, if you're using a coldframe or tunnel.