Hydroponics is the practice of growing plants in a solution of nutrient enriched water. Since hydroponic plants have access to unlimited nutrition and water, they are able to grow up to ten times faster and healthier than soil grown plants. The rapid growth and incredible quality of hydroponically grown plants and produce is resulting in many commercial growers to use hydroponic systems in their indoor gardens and greenhouses. Plants grown in soil-free gardens have the perfect balance of nutrients and water delivered directly to their roots. Crops are not forced to expand their limited energy searching for water and food. They are able to grow faster, larger, and healthier and able to deliver the highest level of vitamin content, flavor, yield, and color possible.

Hydroponic crops do not have to fight the fungi, diseases, and pests typically found in soil and plants mature unhampered by competing organisms. Healthy plants are also less prone to insect infestation, so the use of toxic pesticides can be decreased or even eliminated. The crop's water and nutrient needs are simpler and more effective which helps allow greater control over the crop's life cycle. Instead of the need to guess what the plants need, it will be evident. Without the unnecessary complexity of working in soil, a few simple measurements will quickly determine the plants water and nutrient requirements.

As soil free gardens are all self-contained, they can be just about anywhere including windows, rooftops, and closets. An additional advantage of many soil-free gardens is that they are raised. This will help to put an end to the bending that occurs with other types of gardens. All plants require certain chemical elements for growth and reproduction. Most of these minerals are available in the soil, where they are absorbed by tiny root hairs, and conducted through a vascular system to all parts of the growing plant. In hydroponics, the correct proportions of essential minerals are contained in prepared nutrient solutions available from local hydroponic suppliers. Gardeners may also make their own solutions, but it requires quite a bit of extra work.

Plants obtain hydrogen, carbon, and oxygen from the air and water, but other essential elements such as nitrogen, phosphorus, potassium, magnesium, calcium, sulfur, iron, manganese, boron, copper, zinc, and chlorine must be taken up from the medium surrounding the roots. The elements used for building the compounds of plant tissues are called macronutrients and they are required in large amounts. The micronutrients are necessary only in small amounts and most are part of the enzymes or enzyme activators that catalyze all metabolic reactions. The growing medium must provide support to the plants. Different materials have been successful and include porous rock, pumice, perlite, gravel, vermiculite, and sand, all of which are good choices. Fired clay particles are also used. There are various types of containers and pumping arrangements for delivering nutrient solutions to the garden and draining it back to the storage tanks.

Most common garden pests to not have access to indoor plants, but occasionally white flies find their way inside and can be quite a problem. Both nymphs and adult white flies suck plant juices from the leaves. Screens on doors and windows may help prevent initial infection. Spraying with biologically safe agents may be necessary, but will not help once the infestation is heavy. Beginners to the hydroponic gardening way of life may also question which types of plants are most suitable for hydroponic gardens. The answer to this is peppers, cucumbers, lettuce, and tomatoes. Some types of tomatoes with indeterminate growth will continue to produce year round. Plants can be started from seeds and seedlings. Commercially available rock wool plugs submerged in the media make excellent incubators for germination and seedling growth.