Build a Basic Hydroponic System

A simple plan for an indoor garden you can set up yourself with just a few supplies.


You don’t have to invest in a lot of expensive, high-tech equipment to start an indoor garden. For less than $75, you can build a basic hydroponic system and get a crop growing. The setup explained here is an adaptation of the design introduced by Bernard A. Kratky, Ph.D., an emeritus horticulturist at the University of Hawaii. He developed it for urban food growers, though it works for anyone who wants to start a small indoor garden. It needs no pumps, tubing, or maintenance of any kind. With this setup, you can grow eight plants in a fairly small space. It’s the easiest way to begin your first indoor garden, and you can reuse it for years.


Also needed

Power drill with a 2-inch hole-saw attachment

Water-soluble organic hydroponic fertilizers for vegetative and flowering stages


  1. Drill 8 evenly spaced holes into the lid of the plastic storage bin. Dump out the shavings and thoroughly rinse the storage bin. Replace the lid and place a net pot in each hole, making sure they fit securely.
  2. With the lid on and all the net pots in place, fill the bin with water so that about 1/2 to 1 inch of the pots are immersed (about 9.5 gallons in a 10-gallon bin).
  3. Remove the lid. Following the package’s dilution instructions, add the vegetative stage fertilizer to the water in the bin. Replace the lid.
  4. Set one rock-wool cube into each net cup.
  5. Place the bin so that the plants’ top leaves are 2 to 4 inches from the grow lights.
  1. In about a week, the leaves should start to grow. Even more importantly, the plants’ roots should extend down into the nutrient solution. The roots should be white, not brown. (Brown roots indicate root rot, commonly caused by lack of oxygen. You can’t cure rotted roots, but carefully stirring up your nutrient solution will introduce more oxygen and prevent further rotting.)
  2. The roots grow longer as the fluid level drops, so they continue taking it up. In about 30 days, you will have big leafy plants and only about 10 percent of the original fluid will remain.
  1. If you’re growing a crop for its leaves, they’re ready for harvest at this point. To produce a flowering crop, carefully remove the lid and set it where the roots can dangle without breaking off. Refill the bin to one-third of its capacity with water and add the recommended amount of flowering stage fertilizer. Replace the lid and set the bin so the plants are under the grow lights.
  2. When you are finished harvesting, thoroughly clean the bin. Rinse the bin well before reusing for a new crop.