Making an Inexpensive Indoor Grow Light Box

In an effort to be more self sufficient, I want to start more of my vegetables from seed rather than buying plants at the nursery. Using a grow light will ensure the seeds germinate now so the seedlings will be ready for spring planting. This is the grow box I built.

I considered several ideas. At first I thought I would use a baker's rack but that would require several light fixtures (one for each shelf). Wanting to make this as inexpensively as possible, I used one 4 ft shop light and made a frame out of PVC pipe, then covered it with aluminum foil to reflect the light. The box sits on the floor in my den.

Here is what is needed to make one light box:

Two PVC pipes - 1 inch diameter, 10 ft long
Two "T" pipe couplings - 1 inch diameter
Four elbow couplings - 1 inch diameter
Shop light - 4 feet long which came with chains to hang it. Size T12
Two "daylight" bulbs which have the highest lumens I could find, also size T12.

The pipe cutters shown didn't work for this thick pipe. I used a hack saw instead (not pictured).

PCV glue
Hack saw
18 gauge wire
Heavy duty aluminum foil (18 inches wide)
Painter's tape or masking tape

First install the bulb into the fixture. Remove the tape on the end and pull the pieces out so the bulb can fit.

Align the prongs vertically and insert them into the end pieces, then rotate the bulb a half turn to lock it in place.

Carefully turn the light fixture over. Attach the chains using the "S" hooks provided.

Turn the light fixture right side up and use it to measure the how long to make the cross bar. I made my cross bar extend 3 inches longer on each side of the light. Cut the pipe using a hack saw.

Attach a "T" coupling to each end of the cross bar.

To determine the width measurements, I used my seed trays as a guide. I made the frame a little wider than the trays so the plants would not touch the foil sides. You can adjust the measurements to accommodate the trays you will be using.

Lay the cross bar on top of the tray (centered). Insert the PVC pipe into the "T" coupling, then cut the pipe even with the edge of the tray. 

Repeat on the other side of the "T" coupling to make the end pieces. Do the same thing on the other end of the cross bar and you end up with this.

Attach an "L" coupling on each end, pointing straight up. This is the one place that I used PVC glue. 

The blue PVC glue is not shown in this picture.

Without gluing that joint, the legs twisted like this, making the frame unstable. Since I wanted to be able to take the frame apart for storage, I didn't glue the other joints.

Cut four legs, mine are 17 1/2 inches long. Insert them into the "L" couplings. 

Again the blue glue is not pictured.

Turn it over and you have a frame.

Use wire to attach the light chain to the cross bar. The light should be only a couple of inches above the tray. If the light is too far away, the seedling will become leggy and fall over.

Cover the frame with heavy duty aluminum foil using painter's tape. To create a support for the foil, use 18 gauge wire from one corner to the other.

First cover the sides and back. Make sure the shiny side faces inside. The larger size aluminum foil roll was just the right width. I taped the foil to the pipe and wire frame.

Next, cover the top.

To make the "doors" cut two pieces of foil and reinforce the edges with tape like this.

Tape them to the front along the top edge only.

They can be lifted to access the trays.

I placed a plastic garbage bag on the floor to protect the floor from spills, then added a layer of foil under the trays. Turning up the edges will help to confine any spills.  

This timer is easy to use and we already had it. We use if for Christmas decorations. 15 hours of light will be adequate. 

Watering from the bottom allows the soil to be evenly moist without disturbing the seeds. Pour water into the tray and let it absorb into the soil. The pitcher  I use has a narrow spout, it's the one I use to water my Christmas tree. 

Bessie can make taking pictures a challenge.

The seeds I ordered online should be here any day. I'm ready!

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