When you understand how your greenhouse works you will find that you can get the most out of it. You will feel confident to experiment and try new things. Your results will be better and you will become the envy of your friends. Whether you want to grow ornamental subject or fruit and vegetables it pays to familiarize yourself with the way a greenhouse works. Spending a little time on basic principles will pay off in the end.
A greenhouse is the first, simplest and probably still the greatest solar device known to humankind. We hear so much about solar panels and other high tech gadgets, you may even have one of those handy solar powered devices to charge batteries, but the greenhouse is in many ways a solar powered device too.
The greenhouse differs from other more recent solar powered devices in that it has been around for so long it has been refined to the point that it works really well. It does its job perfectly. That job is heating. A greenhouse uses the sun’s rays to heat up the growing medium and air in an enclosed space. It will do that without any help from us or any added extras.
In theory it would be possible to create a greenhouse that was entirely self-sufficient that could exist without any human intervention once the system was running. The plants inside it would create their own atmosphere by giving out oxygen and taking in carbon dioxide. Such a greenhouse would be a model of the entire planet.
The traditional greenhouse: The traditional greenhouse has vertical sides, closed in lower part, and an evenly spanned roof. It uses space well and the covered lower part conserves heat effectively, making it energy efficient. A wide range of accessories such as shelves and staging is available to suit this type of greenhouse, making it a good all round choice. Many sizes are available, choose one to suit both your garden and the amount of time you plan to spend in the greenhouse. A keen propagator will quickly outgrow a small model.
You additionally need to consider space- if you’re growing broccoli for example you will obviously need greater space between beginner seeds than kale for example. If your aim is to grow flowers or tobacco, bear in mind that different varieties can suffer in excessive heat- a garden building with a greenhouse thermometer might be a good idea as this will help you to regulate the temperature more efficiently. If you want to grow but aren’t good at initial germination, it could be an idea to visit the farmers market at transplanting time to pick up some pre-started plants.
When I say regulate the atmosphere what I am talking about is humidity. Humidity is the amount of water held in the air. The amount of water that air will hold depends on the temperature of the air. Air at 70 degrees will hold twice as much water as air at 55 degrees. When the temperature of the greenhouse begins to fall the water drops out of the air. This is known as the dew point. If plants are subjected to this for a long period they are liable to suffer from various forms of rot, mold, fungus and mildew. This is a natural part of the plant’s life-cycle but not good for us if we want good quality crops from our greenhouse. You can treat the plants with chemicals. There are plenty of fungicides available on the market. But it is better to avoid the problem as far as possible by ventilating the greenhouse.
The cost of greenhouse will depend entirely on the type you require. Polycarbonate greenhouses will be different to glass greenhouses which are often favoured only for their aesthetic appearance as there is little differentiation between the two in terms of cultivation. Plastic greenhouses are also available- these are generally cheaper but can be less stable and easier to puncture. For an attractive growing shelter you could try a Victorian greenhouse or a pressure treated wooden greenhouse
There are many greenhouse accessories available that make growing that little bit easier. These include: wooden or plastic labels to help you remember which species have been planted in which location, greenhouse staging, fixing supports for vines and climbers, reflector mats, greenhouse heaters and bubble insulation for winter- this can reduce your heating costs by up to 30% during winter!