Cold growing.

Warm nights sure seems to help row crops and warm soil helps growth. I used to run hid in winter with LEDs to help. This year I vented a little heat to tent instead just to keep soil warm. Colder soil can slow growth as each little microscopic creature will slow and multiply at a reduced rate. These guys feed my plants.

Just watch your humidity, Powdery Mildew seems to thrive in cool humid places.