The subject of soiless gardening has, in recent years, aroused a great deal of interest and curiosity and been responsible for a great volume of discussion, written and oral. Under various names, such as chemical gardening, chemi-culture, water-, sand- and gravel-culture, hydroponics and others, it has been hailed as a marvelous new invention and the secret of mankind`s future food supply. A lot of money has been spent on equipment and materials offered or recommended as essential to this "new" kind of gardening. And, as might well be expected when anything interests a great many people and makes an appeal to the public imagination, there have been all kinds of experiences with it, including both successes and failures.
Actually while, from one angle, the subject is new, from others it is very old indeed; and, fundamentally, it involves no principles of plant growing that have not been known for a long time. When we talk about feeding plants with essential food substances in solution (which is what all types of soilless gardening amount to), we are right back on the well-known basis of all plant growth. Except for the carbon, hydrogen and oxygen taken out of the atmosphere by its leaves, a plant gets all its nutriment in the form of a very weak solution that it takes in through its tiny white feeding roots. Ordinarily this solution consists of the moisture contained in the soil in which are dissolved the various salts and plant food elements as derived from the soil itself or added by the gardener in the form of fertilizers. If we substitute for the soil and its "soup" a systematically prepared solution of chemicals from which the plant can get what it needs, we have merely changed the method, not the operation. As a matter of fact, that is just what scientists, studying the growth habits and food needs of plants, have been doing in their laboratories for more than a hundred years. So really, the only new angle to this whole thing is the idea of applying this "solution culture" idea to commercial and amateur plant growing.