In cold, windy climates, as well as very hot climates, building a pit greenhouse may be appropriate. Generally, a pit greenhouse is set at least 4ft below grade with a concrete foundation and retaining walls. Exposure to wind is reduced and the ground temperature at the floor is more consistent.

In areas with cold temperatures, building a pit greenhouse using thermal mass materials (concrete base, water barrels, etc), can help maintain temperatures by absorbing heat from the winter sun during the day, and radiating heat at night. Similarly, in very hot climates the use of shade materials over the greenhouse glazing, combined with the cooler, more consistent temperatures in the soil, can help modify summer over-heating. 

Disadvantages of a pit greenhouse can be the cost of creating the pit – excavation and building the foundation structure.  Drainage issues and location of the water table must also be considered when building.

If you are interested in building a pit greenhouse, we can help you with foundation dimensions and details such that one of our greenhouse kits can set on the foundation that you can create.  Call us to talk through your options.