slight leaf curling on small plants

slight leaf curling on small plants
Its been very cold at night, 45 and 50 with rain and lots of moisture.
I have been skipping night time watering.

There no damage and the plants are firm and healthy but why the slight tip curl?

Photo at 11:30 69°F
Perhapse there is no issue at all but its all 12 of my small girls.
The trees are fine.

Forgot to mention they are in 45 gallon smart pots and I water with the 65 gallon pots so perhaps slight over watering?
Also they are growing every day and busting out with buds all over. NOT ONE YELLOW LEAF no damage, no bugs.

OR NO ISSUE AT ALL??

looks like overwatering to me, happened to a couple of mine this year. i cut back on the water and all the new growth was fine. all the leaves that curled under never came back but they stayed nice and green so i just left em.