How to Heat a Greenhouse With Water

Greenhouses have clear walls to facilitate heat and light absorption for plant use. They work well on warm days, but you need to make some adjustments if you plan to use the greenhouse during cold weather to extend a crop's growing season. Your goal is to prevent the greenhouse from losing on cold nights the heat it absorbed in the day. Water is one medium that absorbs warmth and releases it as the temperature drops.

Straw bales
Barrels, 55-gallon
Black paint (optional)

Instructions

- 1
  Stack straw bales against the north wall of the greenhouse to block the cold.
- 2
  Line black 55-gallon barrels along the stack of straw bales. Arrange additional barrels against the length of the south-facing wall of the greenhouse. The color black absorbs the day's heat more efficiently. If you have barrels a different color, simply paint them.
- 3
  Add water to the barrels up to the rim. In the day, the liquid absorbs the heat. At night, the drop in temperature triggers the water to release the warmth it retained, heating up the greenhouse. Refill the barrels as the liquid evaporates.

What Time of Year to Plant Dogwood Trees

What Kind of Lavender Do I Have?

Green & Organic