Hydroponic gardening is the method of growing plants without soil. Plants are fed with the chemicals they require in shallow tanks of water instead of having to take up chemicals which are in a solution in soil. Thus, plants are provided with essential elements in a more readily available form.
The method is gaining in popularity with commercial growers of leafy vegetables in particular. It is a very useful adjunct to the home garden, either indoors or outside. The general procedure was developed as far back as 1859, but it is only in recent years that the practicability of applying the system to small home gardens or commercial projects has been outlined.
There is a variety of systems available on the market, suitable for indoor and outdoor use, in a large price range. Top-of-the-range systems come with circulating pumps, lights etc. but a simple set up can be achieved inexpensively, particularly if you have a naturally well-lit area.
Basically, a hydroponic garden consists of some sort of water-containing tank and something to hold the plants in place, preferably gravel. The tank is filled with a nutrient solution at regular intervals and allowed to drain through the holes in the bottom of the tank. The plants grow down into the gravel and absorb the nutrients. The whole art of hydroponics lies in constructing a gravel which will hold enough water to keep the plants growing vigorously, yet not too much to cause drowning of the plants’ root system. Hydroponic gardening offers the opportunity of improving the quality of food products because all the elements which go to build up the plant (with the exception of the atmosphere) can be surely and definitely controlled.
Another advantage of a hydroponic system is that hard manual labour is eliminated, cultivation abolished, harvesting is simpler and food can be grown almost anywhere year-round.
There are three types of hydroponic gardens – you can have a re-circulating system, a spray system or simply pour on the water and let it drain through. The tank can be made of concrete, timber or plastic-lined metal and must have adequate drainage holes. A mix of several types of gravel material gives good results – possible types are sand, vermiculite, polystyrene foam, crushed brick, cinders, volcanic rock, crushed blue metal to name a few. The gravel is then smoothed and wet thoroughly with the nutrient solution. Enough fluid should be used to saturate the gravel so a little runs out of the bottom of the tank. Plant directly in to the gravel.
Hydroponic gardening is a simple way of introducing food production into your gardening repertoire and is easier to maintain if you are not so flexible as you once were.
Felicite Randall lives with her husband in Tasmania, Australia and is a fourth generation gardener. Now retired, looking after and writing about her indoor garden is one of her main hobbies.