Hobby Greenhouses

A small greenhouse can be a relaxing hobby as well as very useful. It can be used to grow specialty crops such as orchids, germinate seeds and root cuttings for the outdoor garden and grow vegetables out of season. A carefully chosen and constructed greenhouse will give you an interesting hobby that can be enjoyed year round.

The first step is to decide whether you want a homemade or a ready-made greenhouse. Ready made greenhouses are precisely built, so they are usually more attractive than homemade types. However, ready-made greenhouses are usually more expensive and they don't always fit your own situation.

Homemade greenhouses can be made from scraps, and therefore are much cheaper to build than factory made greenhouses. They can also be built to the size that will fit your particular needs.

Before building or buying a greenhouse, you should select a suitable location. The amount of area available will determine the size and type of greenhouse you will build. The greenhouse should be located where it gets maximum sunlight, especially in morning, but preferably all day. The southern or southeastern exposure is the best. The Eastern exposure is the next choice, where morning sun is available. The next best locations are southwest and west. Western exposures will probably need shading in summer. Northern is poor, except for tropical foliage plants, African violets and orchids.

Locate the greenhouse near sources of water, fuel for heating and electricity. This will substantially reduce building costs.

Your next decision will be what type of greenhouse would best fit your needs. There are two basic types of greenhouses: attached and freestanding. The attached greenhouse is built against a building using the existing structure for one or more of its sides. The freestanding greenhouse is a complete, full-size greenhouse separate from your home. The freestanding greenhouse has more growing space, costs more initially, and costs more to heat than an attached greenhouse. The attached greenhouse has the advantage of easy access in bad weather. It is also cheaper to heat because it shares one wall with your house.

The size of a greenhouse is influenced by available space, location, intended use and cost. It should be large enough to house plant benches, a work bench and storage materials. Larger greenhouses are easier to manage because the temperature fluctuates very slowly.

Greenhouses are made with glass, fiberglass, polyethylene, or vinyl coverings. Glass houses are very attractive, permanent, and expensive. These houses should be built by a greenhouse manufacturer or purchased in a ready-to-assemble package because they are difficult to construct. For permanence glass is the preferred material.

Fiberglass is an excellent greenhouse covering. It is lightweight, strong and practically hail proof. It has good light transmission, and requires only a simple superstructure for support. There are poor grades of fiberglass that will discolor, which reduces light penetration. Use a good grade that is guaranteed for 10 to 20 years. The type covered with a poly-vinyl fluoride film resists weathering and extends the life of the fiberglass covering. If you select fiberglass, choose the clearest grade. Do not use colored fiberglass.

Plastic film coverings are inexpensive and temporary. They are light weight and have good light transmission. However, polyethylene constantly exposed to the sun deteriorates during the summer and must be replaced every 3 to 8 months. Polyethylene treated with an ultraviolet inhibitor is more expensive but will last 3 to 6 months longer than regular polyethylene.

Wood, steel or aluminum is used for the supporting framework of greenhouses. Seasoned, construction-grade lumber should be used when building a wood framed greenhouse. When possible, rot resistant woods such as redwood and cypress should be used. If less rot resistance woods are used, they should be treated with copper naphthenate. Do not use ceosote and pentachlorophenol preservatives because they release vapors harmful to plants. Greenhouses built with steel require constant maintenance to prevent the steel from rusting. Aluminum is the best material to use for the supporting framework of a greenhouse. It is lightweight, strong, requires little maintenance and will last many years.

Some greenhouses should be built on foundations. Others, such as plastic greenhouses, can be placed on the ground. In Florida, where the winters are mild, large concrete foundations are not needed. However, glass and fiberglass houses should have a permanent foundation which could be nothing more than wooden sill of 2x6 boards or a 6-inch concrete footing. The foundation should never be higher than the plant benches and no higher than 10 to 15 inches if plants are to be grown on the ground.

Before buying or building a greenhouse, give careful thought to the size, style and kind of control desired. Learn about the problems of people who have greenhouses and check local building codes and zoning laws before you start construction.


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