Greenhouses Optimum Temperature

Clearly, the way to save money on heating is to have a ‘cold house’ and not provide any warmth – but this restricts the range of plants.

If the heating is limited to ensuring the temperature never falls below 7°C /45°F, this is called a ‘cool house’ and enables a wider range of plants to be grown

Keeping the temperature at 16°C/61°F or more throughout the year enables tropical plants to be grown, but the cost is high.

An agreeable temperature compromise – and one that saves money – is just to heat the greenhouse in late winter and spring, when sowing seeds and raising young plants; and in summer to grow plants such as tomatoes that benefit from the protection afforded by unheated greenhouse.

Using an electric or paraffin heated propagator in late winter and early spring to encourage seed germination and the rooting of cuttings saves having to heat the entire greenhouse and reduces heating costs dramatically.