Home gardeners can grow hundreds of plants from seeds in their home by building a grow light setup. Many grow light setup variations will produce transplants, but the one below will last many successful growing seasons.
A trip to the hardware store and a few hours is all it takes to build a successful grow light. The items needed from a hardware store are included here:
Grow Light Supplies from Hardware Store
| Materials | Cost (in 2020) |
| 2x4s- need 176 inches total (2, 8-foot boards) | $6.17 (x2) = $12.34 |
| 1x4s- need 96 inches total (1, 8-foot board) | $6.27 |
| 90-degree braces (4) | $1.98 (x4) = $7.92 |
| Screw eyes (8) | $1.28 (6-pack x2) = $2.56 |
| “S” Hooks (8) | $1.28 (4-pack x2) = $2.56 |
| Wood screws (3 inches) – 12 to 28 | $8.98 (1 lb. box) |
| Wood screws (1.5 inches) – 4 to 12 | $3.48 (box) |
| Chain (40 inches) | $0.66 per foot (4 feet) = $2.64 |
| Shop light ballast (light fixtures) (4) | $14.98 (x4) = $59.92 |
| Fluorescent bulbs (8) | $10.48 (2-pack x4) = $41.92 |
| Timer | $5.98 |
| Power strip | $10.24 |
| Fan | $20.98 |
| Total Cost (2020) | $185.79 |
Frame
The grow light frame should be sturdy enough to support lights and a wooden frame.
Zack Snipes, ©2020, Clemson Extension
First, determine the necessary grow light size. The plant trays used for this setup are 11 inches x 21 inches; therefore, this setup is able to include four standard plant trays.
Cut the 2×4 boards into:
4, 18-inch pieces
2, 28-inch pieces
1, 48-inch piece
Assemble the cut 2x4s using the 3-inch wood screws to hold together the wood. Use 1.5-inch screws and 90-degree braces to build a sturdy rectangular base for the grow light. The 18-inch pieces will be the legs, the 28-inch pieces will span the width of the frame, and the 48-inch piece will be the length of the frame.
Lights
Cut the 1×4 boards into:
2, 24-inch pieces
1, 48-inch piece
Assemble an “I” shape frame with the cut 1X4s for the lights using 1.5-inch wood screws. Once assembled, use screws to attach the individual lights to the I-frame equidistant apart. Make sure the light fixtures are wired and have plugs; if not, wire them before use.
The frame that will hold the lights should be an “I” shape.)
Zack Snipes, ©2020, Clemson Extension
Screw the lights to the wooden light frame. The addition of screw eyes can help with adjusting the chain.
Zack Snipes, ©2020, Clemson Extension
Attach the Lights to the Frame
Drill small pilot holes for the eye screws into the rectangular grow light base and screw them in. Repeat this step for the wooden light frame. Insert “S” hooks into the eye screws. Connect the light structure to the grow lights by adding a length of chain to each “S” hook. Raise the light height daily as plants grow taller.
Insert fluorescent bulbs into the ballasts and plug them into the power strip. Plug the power strip into the timer. Set the timer so that the plants are receiving 16 to 18 hours of light each day. Keep the light tubes at least two inches above the top of the seedlings.
Consider adding a reflective material around the frame to concentrate light on the plants, as plants will often stretch towards light sources outside of the frame. Make an inexpensive reflective shield by cutting cardboard pieces large enough to cover the sides. Wrap the cardboard pieces with aluminum foil and tape. Tack the reflective cardboard pieces onto the side of the frame to enclose the structure.
A grow light set-up complete with frame, lights, foil, timer, and fan.
Zack Snipes, ©2020, Clemson Extension
Place a towel underneath the plant trays to absorb the excess moisture when watering plants to avoid messes. A heater or heat mat is not needed when growing plants indoors. However, spring plants grown in a garage or an outdoor environment will need supplemental heat. Place a fan near the seedlings to produce a gentle sway when plants have two true leaves. This should continue until the plants are transplanted into the garden to aid in the hardening off process. For more information on how to grow transplants using a grow light, see HGIC 1259, Starting Seeds Indoors.
Originally published 02/21
