While the natural protection of woods or hills on the north and the west sides is highly desirable, greenhouses should not be constructed where they will be shaded by other buildings.

The position of the house with reference to the points of the compass is apparently of little importance. A three-quarter span house should run east and west to get the full benefit of the sun, while the even span house should probably run north and south in order to secure a uniform distribution of light. Some growers compromise and build their houses northeast and southwest. With the modern house, about 95 per cent of which is glass, ample light will enter the house whatever its position may be.