The book ‘Hydroponics’ (Soilless Gardening) is a subset of hydroculture, and it is a method of growing crop plants (Vegetables, fruits and flowers, etc.) using mineral nutrient solutions in water without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only, or in an inert medium such as perlite, gravel, sand, etc. It is the art and science of growing crops with balanced amounts of plant food in the form of fertilizing nutrients and water, instead of depending on the earth. There are many advantages over ordinary soil methods, i.e. higher yields, quicker growth, lower costs, no digging, weeding or hard work, and much saving of space (land), enabling householders and flat dwellers, people living in congested conditions, or those without enough space, or any fertile land to produce year-round supply of healthy vegetables, fruits & salads, beautiful flowers and decorative plants at little experience and without trouble with low expenses. The book is in ten chapters comprising of the subjects Meaning of Hydroponics, Early History, Advantages, Problems in India, Practical Developments, Advances in Technology; Origin, Techniques : Aeroponics, Static Solution Culture, Continuous-flow Solution Culture, Passive Sub-Irrigation, Ebb and Flow/Flood & Drain Sub-Irrigation, Deep Water Culture, Fogoponics, Systems & Methods, Ecology & Economics of Hydroponics; Substrates : Expanded Clay aggregates, Growstones, Coir, Rice husks, Perlite, Vermilite, Sandoponics/Sand Culture, Gravel, Wood fibre, Rock wool, Sheep wool, Brick shards, Nutrients solutions, Commercial Venture, Advancements; Current Usage, How Plants Grow, Differences from Soil; Simple Growing Units, Water supply, Setting up a Hydroponic Unit; Feeding Plants, Preparing Mixtures, Rate of Application; Sowing & General Care, Light-Air-Temperature-Cleaning,