How to Build an Indoor Hydroponic Garden


An indoor hydroponic garden allows you to grow plants year-round, regardless of the weather. You control the light, nutrition and temperature for optimal growing conditions. Indoor growing also isolates plants from many pests and insects that can plague an outdoor gardener. More experience and care is required for successful indoor hydroponic gardening, but the rewards of sharing fresh herbs and vine-ripened vegetables on the coldest day of the year make it all worthwhile. Start with a simple floating raft garden system to get comfortable with hydroponics. Once you understand the principle, you can grow a large variety of plants via hydroponics.

Step 1

Cut the foam insulation so that it conforms to the sides of the plastic tote, but will be free floating without interference from the sides of the tote.

Step 2

Cut 2 1/2-inch holes in the insulation to accommodate the net pots. Most totes can accommodate six to eight pots, while allowing room for the plants to grow.

Step 3

Germinate the lettuce seeds between moist paper towels. When the seeds germinate, place each plant onto a small piece of damp sponge. Keep the sponge moist with water until the first leaves appear.

Step 4

Make up the nutrient solution according to the package directions and dilute it with an equal amount of water.

Step 5

Place the tote in a sunny window, if possible. Supplement the light with an adjustable grow light placed directly above the tote.

Step 6

Place the small plant and sponge into the net cup. Fill the tote with the diluted nutrient solution and place the foam onto the surface. Put the net cup into the hole in the foam so that the bottom of the cup just touches the top of the nutrient solution.

Step 7

Adjust the level of the light as needed to keep the light as close to the plants as possible without burning them. Use your hand to determine how much heat is radiating onto the plants.

Step 8

Change the nutrient solution once a month, between crops or after the level drops for a second time after topping it off with water.

Things You'll Need

  • Large plastic tote, dark color
  • Foam insulation
  • 3-inch net pots
  • Hydroponic nutrients
  • Lettuce seeds
  • Sponge
  • Paper towel
  • Grow light


  • University of Florida IFAS Extension: Building a Floating Hydroponic Garden
  • University of Arizona Extension: Six Systems that You Can Build
  • Iowa State University, Reiman Gardens: Lighting & Houseplants
Keywords: indoor hydroponic garden, indoor raft system, indoor floating garden

About this Author

Diane Watkins has been writing since 1984, with experience in newspaper, newsletter and web content. She writes two electronic newsletters and content around the web. Watkins has a Bachelor of Science degree in chemistry from Clemson University. She has taken graduate courses in biochemistry and education.