Even a small greenhouse opens up new gardening horizons - from early vegetables to orchids. With equipment in ready supply it's possible to create a complete controlled growing environment which will run on auto pilot.

One of the biggest advantages of a greenhouse is that it frees a gardener from dependence on the weather. Inside the hothouse, under cover of glass (or plastic) you can grow plants which would suffer badly from the rain, wind and cold if grown outside.

Greenhouses can be heated or unheated. An unheated greenhouse offers no protection against frost, but it will provide your plants with more warmth during the growing season. The extra heat trapped by the greenhouse speeds up the ripening period and produces better flowers from decorative plants. Unheated greenhouses also offer protection against the elements - wind and rain - and shield your crops from attack by birds, pests and animals.

A major advantage of greenhouses is that they extend the growing season. Plants can start growing early in spring, and either be kept in the greenhouse or later transferred to the garden. In the greenhouse they will continue growing well into fall.

This lengthened growing season is achieved by the heat of the sun being trapped by the glass or plastic covering during spring, and, in the fall, warmth accumulated in the soil and brickwork during the hot season is released back into the greenhouse.

A typical use of unheated greenhouses is to grow tomatoes during spring and summer, and, in fall, when the tomatoes have been discarded, late flowering chrysanthemums can be cultivated to brighten the approach of winter. It's also quite common nowadays for gardeners to grow grapes and melons in unheated greenhouses.

Unheated greenhouses are also suitable for a wide range of half-hardy shrubs, lilies, gladioli, annuals, and other bulbs which will produce the finest blooms.

Lettuces, radishes, French beans, carrots, potatoes, and all out-of-season vegetables which are normally grown in cloches or frames are equally suited to growing in unheated greenhouses.