What to expect from a greenhouse

A few pointers to what a greenhouse is designed to do, and what you should not expect from a greenhouse.

A greenhouse is a garden building solely designed to trap the suns heat and give you a warmer growing environment than the outside. A typical unheated greenhouse will provide you growing conditions roughly equivalent to an outside area around 1000 miles to the south of you if you are in the northern hemisphere.

For a greenhouse to work as designed it has to be placed in a position where it will receive maximum sunlight, if placed in significant shade it will not perform as well as it should. Greenhouses are at their most valuable early and late in the season when the sun is lower in the sky therefore any shading that is around the greenhouse will cause maximum problems. During the high summer if scorching is a problem there are several shading options available to reduce the amount of light coming in. It is always best to position in the sunniest place possible.

Your greenhouse is a building that is expected to be filled with plants either directly into the soil or into containers therefore it is designed to be tolerant to water from inside and out. Hosepipes and watering cans are expected to be used inside, they are not however designed to be in any way completely watertight from the outside. Greenhouses will generally all allow a small amount of water to enter during heavy rains. The design of the roof vents which hinge directly onto the ridge bars mean that water ingress is virtually unavoidable. Lean tos are particularly vulnerable as they tend to have a shallower roof pitch which often means roof vents will drain backwards to the ridge when fully open. If you are looking for a conservatory please do not expect a greenhouse to be a budget alternative, if you carpet a greenhouse it will almost inevitably end up wet.