Here's the rack I just built for about $150. I had space in the furnace/water heater room for a 24" x 18" x 6' bakers rack on wheels. That was half the cost ($75 on Amazon). The lights I used were 24" dual LED tubes (18w, 1800 lumens, 5000k), 4-pack on sale for $60 at Amazon (normally $80). And one roll of 24"x25' Reflectix ($21 at Home Depot).

I've never used Reflectix before but this stuff is GREAT. While I've only started using my grow rack, I'm guessing that enclosing the whole unit in shiny Reflectix reduces the amount of lighting needed by bouncing it back and forth so much. It's super easy to cut with scissors and mounts easily to the rack (and itself) with plain old packing tape. After mounting the lights, I cut and taped Reflectix to the back and both sides. That left a long section to tape to the top-back that just rolls over the top and front to enclose it. When I need to get into it, I just roll it up from the bottom and it sits on top.

The lights came with hanging cables. I just looped them over shelf rack and hooked them to the shelf with little "S" hooks I formed from stiff bailing wire (or just buy some "S" hooks). That way I can easily lower the lights for seed-starts buy hooking them to a different rung.

Hey, that's pretty neat.

What are you doing for air movement inside the enclosure? Any way to cycle air out of the enclosure and bring new air in?

Hmmm, hadn't thought about that. The bottom is open with probably 3" all around, and there are small openings along the front roll (I purposely didn't seal it all up). If it needed more air flow, I could always untape the top/front section and tape it further forward to leave a gap in the top-back. And/or just leave the front rolled up and open a few days/week. It doesn't really need to be closed on all 4 sides, but I figure it'll get maximum value out of the lights when it is fully enclosed.

I live in Colorado where we have pretty low humidity, so I don't think airflow is quite as important here as it might be in a more humid environment. Plus the furnace/water heater room is vented to the outside so there is a little fresh air that seeps into the room as well. But I'll keep an eye on it. Thanks for bringing it up.

The point of the Reflectix wasn't to seal the air in, it was simply to keep the light in using something sturdier than aluminum foil.

Air movement can actually be very important to plant growth, even in places with fairly low humidity. As plants transpire, the humidity immediately around the leaf surfaces increases - and without air flow, that humidity just sort of sits there and can actually slow down further transpiration (which can slow growth).

A good article about this:

https://gpnmag.com/article/the-boundary-layer-and-its-importance/

Just food for thought.

Never heard of Reflectix before - it looks neat! Right now I am using Orca film attached to corrugated plastic for the walls of my grow area.

Thanks for the link. I'll have to keep an eye on it.

I'd never heard of Reflectix before either, until I saw it mentioned somewhere else (someone else's grow rack YouTube video). Found it at Home Depot and it seems to work great for this purpose.

I'd already been growing some lettuce in my outdoor greenhouse, until it just started getting too cold and I had to bring it inside (it's only a small plastic greenhouse that protects from light freezes and extends the seasons a month or two). I moved those pots in this grow rack for a week (as shown in the pictures) and I could see significant growth. The real test will be to see if there's enough light to keep seed starts from getting leggy.

I like the stand setup!

for lights, another option would be using a couple clamp lights with 16w leds. Each shelf has 3200 lumens of 5000k light in the photo below.

The clamp work lights are $7 and I got four 1600 lumen leds at Lowe’s for $1.20 each.

I used dryer vents as the hoods / reflectors.

Nice. I do have clamp lamps too (and a few swing-arm desk lamps), and that's what I use when I do seed starts just sitting on the counter. The only problem with them in the rack I was building is that they take up more valuable space than the tubes. I'd have lost a shelf or two to fit in the bulkier clamp lamps.

I especially like these naked tubes, that don't have any reflector on them at all. They take up the minimum amount of space while providing fairly even lighting over the width of the rack.

I know it's far from a perfect measure for plant lighting, but my cell phone app reads about 5400 lux sitting on a shelf with the front flap closed. It reads about 5100 with the flap open, so it appears the Reflectix does give it a nice boost. I should have tested it before putting any of the Reflectix on, just to get a baseline. I'm guessing it would have been in the 3500-4000 range.

I do have some basic sockets on a cord too. If I need a temporary boost, I can just plug a few in and dangle from a rack. Costco had a 10-pack of the similar 100w-equiv LED bulbs that you showed for something around $2/bulb that I picked up a few months ago.

Just a little follow-up on using my new grow rack. Seems to be working OK on my first batch of seed starts. I planted some spinach, lettuce, green onion, chives, basil, and cilantro seed in 6" pots 19 days ago. I was curious to see if the 1800 lumen lights (boosted by the Reflectix on all 4 sides) would be enough to keep them from getting leggy. I think these look OK, although it's only my 2nd year growing from seed so I'm not totally sure. Do these look leggy to anyone?

Here is my set up

First picture has romaine lettuce on the left container; the right container contains brocolli seeds. The last picture is a trial tomato seeds. The rest of the shelves are my house plants. The light is 4' led fluorescent plug in.

Can I suggest an Aerogarden bought on sale , roughly $150, plus miniature lettuce or raddichio? Breen or Truchas?

My experience is that the the small fittings of a homemade system add up fast. They quickly equal and then surpass the cost of your specialty equipment for the home made setup. Plus, there's a considerable amount of time futzing with the set-up. Not a problem if it's quality time with your son.

I got an Ispring tds meter. I keep the fluid at 500 ppm to 1000 ppm. I got Maxigrow at the doper hydroponic store for $17. I'm pretty sure that the lights will burn out before I use it all.

A couple salads apiece per week I'm guessing.