At what temperature would a greenhouse be damaging to young plants?

Question

The plants consist of tomatoes, peppers,cukecumbers,ect .We can never plant these till after memorial day

Answer 1

Depends on the plants and the time of year. Seedlings of cold tolerant plants will take lower temps than seedlings of tropicals. Should have mentioned the plants.

If the plants are bigger, say a few weeks older, the sudden chill may induce bolting in plants far earlier.......for example if you were growing onion sets, the onions would never develop mature bulbs but would immediately want to form flowers.

So, if these next few days the plants seem ok, then they'll probably continue to grow. But some may want to set flowers earlier than you expect, those who use a chill period to set flowers.