How to Build a Fluorescent Grow Box


Grow boxes can help you germinate seeds and grow seedlings for outdoor spring planting. Grow boxes fitted with either a commercial or home-built hydroponic system can help you grow vegetables and plants in dark areas of your house over the winter. You can use an old filing cabinet or bookshelf to make a box tall enough to accommodate the maximum expected height of your plants. Building a grow box is not difficult and can allow you to garden indoors during the coldest times of the year.

Step 1

Choose a box tall enough for the maximum height of the plants you are growing plus about a foot for the light fixture. You will raise the light inside the box as the plants grow. The light must be 3 or 4 inches above the tops of the plants and may require an additional 6 inches for the fixture.

Step 2

Place the fixture on top of the grow box and mark the two sides of the fixture with a pencil.

Step 3

Make two marks on the lines in the center of the box. You will drill holes here to pass chains through to raise and lower the fixture.

Step 4

Drill two holes in the top of the box about twice the thickness of the chain. For example, if you have 1/8-inch chain, drill 1/4-inch holes.

Step 5

Cut two chains the height of the cabinet plus 1 foot. For example, if you are growing tomatoes, you will likely need a 5-foot-tall grow box. Cut the chains to 6 feet long.

Step 6

Attach the chains to the center of both sides of the light fixture. Some fixtures may be heavier on one side. You may have to adjust one or both chains to keep the fixture as level as possible when suspended.

Step 7

Screw two cup hooks about an inch toward the outside edge of the box about an inch from the chain holes. The cup hooks should be small enough to pass through the links in the chain. You will hook the chain to these to raise and lower the fixture.

Step 8

Set the fixture inside the box and pass the loose ends of the chain through the holes in the top of the box. Raise the fixture by pulling the chains through the holes and secure the chain on the cup hooks.

Step 9

Plug the fixture in to a timer and set the timer to provide between 12 and 15 hours of light per day. Install a full spectrum fluorescent or fluorescent grow light bulb and igniter in the fixture.

Step 10

Place pots or a hydroponic system inside the box and adjust the lights to about 4 inches above the initial growth medium.

Things You'll Need

  • Wood or metal box
  • Fluorescent fixture
  • Full spectrum fluorescent bulb
  • Drill
  • Drill bits
  • Chain
  • Cup hooks
  • Electrical timer


  • University of Florida Extension: How to Build a Plant Lighting System
  • Garden's Cure: Beginner's Guide to Grow Cabinet Design
Keywords: homemade grow box, indoor gardening, grow light system

About this Author

Christopher Earle is a freelance writer based in Denver, Colo. He has been writing since 1987 and has written for NPR, The Associated Press, the Boeing Company, Ford New Holland, Microsoft, Active Voice, RAHCO International and Umax Data Systems. He studied creative writing at Mankato State University in Minnesota.