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Gardening is a very popular hobby especially among homeowners, which means the over-thirties really. A nice-looking garden certainly does make a house look better. However, bedding plants and fruit trees can be quite expensive, consequently a lot of gardeners want or already have some form of greenhouse so that they can cultivate plants themselves and grow more exotic flowers and fruits.

It really depends on the kind of greenhouse you have and where you live, but many greenhouses can be ‘adjusted’ to grow most kinds of plants from around the world. Global warming has helped in this respect too. In most places, you can grow grapes from France or orchids from Thailand where as a rule such plants would die outside.

Therefore, having a greenhouse is a little like keeping a tropical fish tank. The gardener has brought those plants to a region of the planet where they cannot support themselves. They should not be there, so it is up to the gardener to create the circumstances in which those plants can thrive. This has mostly to do with ventilation, temperature control, humidity and lighting.

Lighting is especially important in the winter in the temperate zones, because the duration of sunlight can be as low as two or three hours and the quality of light can be very bad. Just because it is light enough for you to see where you are going does not mean that it is bright enough for a plant to sustain itself.

Light in the tropics is always strong for most of the day and there is possibly only an hour difference between daylight hours in the summer and the winter. Usually there are about twelve hours of light and twelve hours of darkness.

Obviously, this means that is likely that you will have to supply some sort of artificial lighting if you have a green house. I have never seen a greenhouse in the tropics.

Which sort of greenhouse light you buy, really depends on the type of plants you intend growing. If you want tropical orchids, for instance, you will have to have a high level of humidity, which means that your light will have to be water-resistant or even waterproof.

Another factor to keep in mind is the photo period – the length of time you will need to provide light. This could be as much as twelve hours at a stretch in the winter, so you will have to have a light that can handle that without becoming over heated

Different lights produce different wavelengths of light, that is light from different fields of the spectrum. These different wavelengths of light yield different results, so you will have to know what you want to accomplish before you can buy a greenhouse light. Spectrum colours are good for promoting the growth of orchids, but you will have to do some research, once you know what you want to grow.

In conclusion, if the greenhouse light is to be used for many hours a day, look out for an energy efficient light. It may be more expensive, but it will pay for itself. Cheaper lights often waste energy by generating heat, but more heat is not always a good idea. It is far better to regulate the temperature separately.