Moonlight, I really honestly believe the cannabis is a very hearty plant and can withstand quite a lot, it is one thing to consider when shopping for the best strain for your general location. If you are planning on covering your plants it is best to search futher into proper technique as I heard sometimes that is harder on the plant due to condensation forming on the leaf. Last spring I had temps most nights hovering at 32 to 35 degree's, the sun had warmed the earth enough that the evening radiant heat
was enough until first rays of dawn. That was KC36 strain (KC Brains) which claimed was Indica cold tolerant. I am guessing with the plants still in the pots you have hardened the plants off properly before setting them into soil? If not check into how to do that as the plant needs a little time to get used to direct solar light, wind etc. Hardening off is just allowing the plants a little time each day outdoors to strengthen before full Mother Nature takes over. Best of Luck my friend.