I used a shelving unit that had shelves that were not adjustable but my light fixtures were hung on chains and could be raised or lowered easily. I have grown African Violets, Iris Seedlings and Hosta seedlings successfully on mine. I liked the easily adjustable light fixtures because I could raise the lights to water the plants and then lower the fixtures. The African Violets loved growing under the lights.

Paul - I considered doing that too, but those shop lights were a little awkward to raise and lower. I was also concerned about bumping the shop lights (and possibly breaking one of the light tubes) when trying to adjust their height, so that is when I decide it was easier and probably safer to just raise and lower the shelves. Could explain how you rigged your shop light to make it adjustable?

One way to do it is to hang them from "chains". Sorry I don't recall the name, but it is a cheap, light chain where each link is just bent, not welded.

I unbent the last link in the chain to form a hook, made a loop of the chain where it passed through the fixture's hanger, and used that hook to attach the end of the chain to the hanging length. WHERE I hooked the hook controlled the length of the chain, by changing the length of the loop.

I'm sorry, that probably makes no sense at all, and I don't have a photo!

You can also just dangle the chain down from the upper shelf, and add a hook to the fixture. Just hook the hook into the dangling chain when the fixture is the height you want. But then I felt I had to tie the extra length of chain out of my way so it didn't hang down into the plants.

P.S. You have to support the weight of half of the fixture with one hand while fiddling with the hook using the other hand. Then lift the other end of the fixture, and adjust that hook.

I think I have the general idea of how you did it. The awkward part for me was that the lights were longer than my shelving unit was wide. I had to center the shop lights and they were still sticking out on both sides of the shelving unit. I was mainly worried about bumping the shop light and breaking a bulb. Hanging from a chain, they moved around a lot unless I did secure them tightly under the shelf. I tried to figure out the best way to hang the shop lights and what I came up with seemed the most secure. I tend to think "outside the box" .....

Rick explained a method similar to mine, hanging the fixtures on chains with hooks. The shelves on mine had holes in them so it was easy to make the upper support. My greatest success was when I had the lights very close above the plants. If the lights were to far from the plants the plants quickly became thin and lanky.

They do sway, and I can see where side-braces would make it tough.

You might be smart to bolt them down tight, in case someone bumps into the rack hard.

By the way, just in case SOMEone might ever be as dumb as I was, don't do the following:

I stood a 4' shop fixture on its end, on the floor, so it would shine "sideways" onto the bottom four feet of some plants.

Then I was about to go on a trip, and watered more heavily than usual.

Water flows down.

Some water flowed onto the floor (where I was smart enough to protect the floor from water, but NOT smart enough to protect the 120 Volt lighting fixture from water.

Fortunately, I smelled "something funny" just before I rolled my suitcase out the door.

It wasn't actually very funny at all, and would probably have burned the house down if I had been 30 seconds faster.

P.S. That's how the British Columbia police said they used to catch hippies growing pot indoors. "We catch them when they burn their house down".

I bought my shelf unit at Home Depot It is made out of a material similar to PVC and comes apart easily when not in use. It is quite sturdy....doesn't wobble. I would take a picture of it but right now it is a catch-all...........full of pots and other items.....no plants.

I've had a similar setup for many years but built from pvc pipe. It has four shelves that accommodate 4 trays of plants per shelf, with two shop-lights per shelf. Used coated wire shelving units to set the trays on.

As other's have done, I hung the lights from chains to adjust their height, and never had any problems with breaking the bulbs. I haven't noticed much difference in growth rates between all cool-white, and mixed cool and warm-white bulbs.

Don....that looks very similar to mine and I see that you have the lights just inches above the plants.

Cinder blocks and 1x12 shelving...freecycle... jack chain, Ess hooks, Eye hooks...4 ft. fluorescent T12 light kits...

Paul, Rick, Don, and Linda - Wow! Those are some great grow-light shelving ideas! Glad to know that many others here also came up with some ideas on how to create their own grow-light shelving units for Winter sowing and growing! Excellent ideas from all of you! Pretty neat to see the materials some of you used. (Probably much cheaper than my idea, too!) Thanks for sharing your ideas and photos for others to consider! If you can build it cheaper .... go that route! This shelving is only used for a few months out of the year for the majority of gardeners.

I like the idea of being able to raise and lower the lights via the chains. For me, it wasn't that hard to adjust the shelves. But the light chain adjustment might be easier and quicker. Thanks for sharing that idea, too! Y'all have so many good ideas!