Anyone who has done gardening in the open will basically be able to apply their knowledge to greenhouse gardening, as there is really not all that much difference.
There are basically six different reasons as to why greenhouse gardening is used, and they are: raising plants for winter use, holding over garden plants to be used as parent plants for next season, getting an early start for tender plants started from seed, increasing the possibilities of a greater variety and continuous supply, easier culture of small vegetables for winter use and to propagate and experiment with various plants as a hobby.
THE FIRST STEP
If you are interested in greenhouse gardening, then the first thing you are going to need to do is choose a site for your greenhouse. This is actually one of the most important aspects of all, as where you decide to locate your greenhouse is going to greatly affect how your plants turn out.
You want to choose a level, clean site in a low-traffic area, and you need to make sure that your greenhouse is going to receive the maximum of winter sunlight possible. There are a few things in particular that you are going to need to consider when you are deciding on a site for your greenhouse.
For instance, you want to consider the change in the angle of the sun between summer and winter, as well as shadows cast by existing structures and trees, whether growing trees are going to block sunlight from your greenhouse in the future, and whether any existing deciduous trees are going to allow winter sun.
THE WORKSPACE FOR YOUR GREENHOUSE GARDENING
The next step in the greenhouse gardening process is to ensure the best workspace. Your greenhouse interior should always allow enough room for potting plants and moving about comfortably, and you also want to take into consideration the height of the benches and tables that you plan on using inside.
Temperature is also important to take into consideration with greenhouse gardening, and the more sun that is provided, the more heat the greenhouse will be able to produce. However the more heat is produced, the more ventilation is going to be needed, and so you want to place a thermometer in the shade near the middle of your greenhouse so that you can always keep track of the temperature inside and make sure that it is not too hot or cold.