DSCN6987 Published February 11, 2015 at 1000 × 750 in This week in the Greenhouse (week of 1-25-15) ← Previous Next → On the left you can see the plastic walls we use to separate warm and cool bays. During the day we can roll them up to get air moving and keep the warm bays from getting too humid, and at night we can drop them to heat the zones as needed.