Safer® Hydro FAQ - What Is Hydroponics?
Strictly speaking, hydroponic gardening is growing plants without soil and feeding the plants with a liquid solution of dissolved nutrients. Hydroponic growers can employ one of the variety of systems for keeping their plants hydrated and nourished, such as deep-water culture, ebb-and-flow (aka flush-and-drain), nutrient film technique, and aeroponics. Don't fuss over this definition. Growing plants in pots of soil or other natural material indoors and feeding and watering them through a drip system still meets the general definition of a hydro garden.
2. What does N-P-K mean?
Dr. Hydro is not trying to stir up disturbing flashbacks to your 10th grade chemistry class, but just for a moment try to picture the chart on the wall called the "Periodic Table of Elements." Each of the elements on it has a symbol like those used in formulas such as H2O and NaCl. N represents nitrogen, P is for phosphorus, and K is potassium (since P was already taken). To botanists and gardeners, N, P, and K are known as "macronutrients," the most important elements to plants and therefore key ingredients in fertilizers. The N-P-K ratio listed on fertilizer packages defines the relative amounts of each nutrient.
The Safer Hydro FAQ is provided by Dr. Hydro, better known as Scott Meyer, an editor at Organic Gardening magazine for 20-plus years and author of The City Homesteader (Running Press, 2011).