I've used a hodge-podge of different shoplights for several years to grow my transplants with. The last fixture I bought was an LED fixture from Wallyworld...a "Hyper Tough" 5000Lumen/5000k-temp unit...this is its second or third year in use and is working great. The other two old fixtures consisted up one *very* old fixture with some blueish florescent tubes in it and another, newer fixture that had some retro-fit LED tubes in it. The newer Hyper Tough was notably brighter than the two older lights. So, I finally bit the bullet and retired the old/odd fixtures and after a pilgrimage to Wallyworld now have three matched Hyper Tough LED units.

I had been using some pieces of foil-backed foam board insulation around my shelving to help reflect stray light back on the seedlings. That worked but it had it's drawbacks...the pieces were kinda clumsily propped up here and there. I probably could have done a much better job using the pieces but they really didn't cover all the area I wanted covered so lots of light wasn't used by the seedlings. I looked online at Wallyworld for some mylar "emergency blankets" but they showed them out of stock. Knowing Wallyworld's inventory system (I'm going to be nice here) sucks, I still went to the camping department and looked for the emergency blankets. Sure enough, they had three or four of them hanging on the little strip hanger beneath some "clear emergency ponchos"...so I grabbed one. These blankets are like 52"x82" (or pretty close to that, my memory, well... ) so they cover a lot of area, are *very* lightweight, and reflect a lot of light!

It's difficult to show the difference in illumination with my old cellphone camera very well, but...

So, without much more "ado",............"The Setup"!!!!!

Small lamp on, shoplights off...

Small lamp off, shoplights on...


Peeking beneath the lights...

"The Shelf"...14"x48". I should be able to get three containers holding 11 or 12 20oz cups each...


And for reference (from 2020)...


Anyhow, I showed you mine....

And for all you grammar police...yep, I spelled it as "your's" in the title.

I just set mine up a few weeks ago. The cardboard boxes worked well last year so I saved good sized boxes for it this time.

2 heat mats under the lower box, temps of both boxes stay above 65 or so it seems, even in the chilly back room of the garage.

The lights are those Walmart cheapies too, they work nice. Really disorienting to look at tho, so the closed boxes help with that and heat as well.

Nice setup! Your lights are a definite color variation from the ones I have...are you using the LED lights or florescents with grow-light tubes in them? Looks like about 40 cups in that lower box! Conserving the heat is good, too, I like the "tent" effect you have going. I'm hoping we see a warming up happening in the next couple of weeks...the old trailer gets cold and I don't want to have to use any auxiliary heat...unless I have to. If you note my last photo of the old setup you'll see an incandescent light bulb hanging at the bottom of the shelving...for heat.

@binfordw , after reading your reply I got to thinking about how your boxes do indeed hold in the heat from the bulbs. The shelves I use are made from metal rod material so there's big gaps above the shoplights and the heat from them just floats away. I'm thinking that since I'm not using the foam insulation that I may lay it down on the top rack (light fixture support) and maybe it will reflect some of the heat back down. I don't think it would be in the way or cause a problem.

Yea the closed boxes are mainly for warmth. I keep them in a middle room of the shop, that only gets moderately heated- sort of a breezeway for the main heated part. I'm not sure if the lights put out much heat really, but it does seem to stay warm. I laid some foam I had saved for spacing trays up closer to the lights on top to somewhat aid in insulation perhaps.

These are my early starts, trying to keep it limited!

I think I might wait and start the rest in the greenhouse once the temps are ok.

Oh- the lights are the Walmart "hyper tough" brand led grow lights. They are about $12 each.

https://www.walmart.com/ip/Hyp...

Maybe I should've tried those cheaper lights but I thought they wouldn't work. Do you have to put something reflective to work well? I got a grow light from Menards. It's really warm to touch the top.

binfordw said:Oh- the lights are the Walmart "hyper tough" brand led grow lights. They are about $12 each.

https://www.walmart.com/ip/Hyp...

I'm using these 48" Hyper Tough LED shoplights. They are stated as being 5000-lumen and 5000k temperature, both specs are good for growing seedlings to transplant size. I inserted a Kill-a-Watt meter between the wall-receptacle and the plug for the power-strip to the lights (basically where the timer will be located later) and it looks like the lights are pulling a little more than the specified 45W each....the wattage for three of them was (as I recall) around 150 watts. So, the lights *might* be a bit brighter than the stated 5000 lumens.

Have you considered lining the walls of the boxes with something reflective? Aluminum foil, mylar, white paper, etc.,?

Seeing your setup is getting me anxious to get some seeds started...I've just gotta have patience...patience...PATIENCE!!!!!

Cam78 said:Maybe I should've tried those cheaper lights but I thought they wouldn't work. Do you have to put something reflective to work well? I got a grow light from Menards. It's really warm to touch the top.

Lumens and temperature (K) are the two important things to consider with your light...and low heat output. Years ago I had some shop lights and I had bought some "grow light" tubes to go in them. They seemed kind of dim. I started reading and learned about mixing low and high Kelvin temperature lights together to create a "broad-spectrum" light. Later I learned that the different colored lights actually do different things in regards to growing plants.

Light "color" is measured in Kelvin-degrees, thus the "K" you see in lots of spec. The bluish/whitish high temperature lights, in the 5000k range, promote vegetative growth...leaves, stems, roots. Lower temperature reddish-color lights, down in the 2700K range, promotes flowering. Growing seedlings we are really only worried with the upper temperatures to promote vegetative growth.

Lumens measure the amount or intensity of the lights...the more lumens the more energy emitted...and seriously you can not have too much (unless, of course, it produces too much heat). Really, in comparison to the sun what we can produce for our seedlings is much, much, much less...but it can be completely adequate. I won't purchase anything lower than 5000 lumens. I see some LED lights on Wallyworld that you have to order that go on up to 8000 lumens.

The reflected mylar that I have installed is to enhance and try to milk every lumen I can out my lights. Like I mentioned, our lights are woefully weak compared to the sun so we want all the lumens possible hitting the plants. The mylar does a great job of reflecting "lost" light. I'd been using foil-backed insulation but the pieces were getting frazzled and I never did attempt to "properly" set them up....just prop them here and there. The mylar (emergency blanket from the camping area at Wallyworld @ $2.74) was an easy and very efficient replacement for the foam insulation. Time will tell how well it holds up...if I get one season out of it I'll be satisfied...two seasons and I'll be elated! So, to answer your question regarding using something reflective...I'm thoroughly convinced that it will help. Is it required?...I wouldn't think so. But, for an enhancement to your lighting system that is so cheap...why not? The cost and effort seems very much worth the effort to me.

What kind of tubes are in your grow-light? LED? Florescent? The heat you feel is lost energy. LED fixtures *usually* do not produce a lot of heat above (or below) them. How long have you had the fixture? Still within the return window? The $20 shop lights at Wallyworld will do the trick...two of them side-by-side would work great for you. Use a power strip to plug them into, insert a timer between the strip and the wall receptacle and you have your automated lighting system. I run mine 100% of the time for 16 hours per day. My seedlings wake up before sunrise and stay awake until 9-10pm.

Just looking at your setup, is that the normal distance you keep the light at from the seedlings? I usually have mine within an inch or two of the top of the seedlings...it keeps them from getting too leggy...making for more sturdy transplants. If the light is too far away it will be weak...only a an inch or so can make a big difference. Check out: Inverse-square-law...that explains how light dims with increased distance. Worth comprehending. And, you can really boggle somebody's mind with the knowledge at the next potluck meal you attend!!!

I haven't thought about trying reflective material. The seedlings seem to grow pretty well. Maybe I'll give it a try in the future.

I have a couple of "good" grow lights from menards that were $40-50 something a piece, but other than the light being easier to look at- more natural, the plants don't seem to notice a difference.

I went ahead and added the front reflector to the plant stand. I've used this sheet of foam insulation for several years but always had it "rigged" with some cheap tape that I was forever wrestling with...both to keep it attached and to keep it stable when I flipped it up.

So, I ended up making a very high-tech design-changed to the front reflector. I took a screwdriver, punched a hole in two corners of the foam insulation, ran some old cord through the holes and tied it off to the upper rack. It is now very secure and the slack from the upper rack to where the cord ties onto the panel leaves the perfect amount for me to flip the panel up and for it to stay there! I used some of my NASA-engineering skills to accomplish this!!!
Closed...

Opened...


There's only one shop light burning in there. When I turn on all three it's SUPER BRIGHT...60-cycle electricity appears to mess with the rolling shutter on my cellphone and leaves black bars in the photos when all three fixtures are on.

binfordw said:I haven't thought about trying reflective material. The seedlings seem to grow pretty well. Maybe I'll give it a try in the future.

I have a couple of "good" grow lights from menards that were $40-50 something a piece, but other than the light being easier to look at- more natural, the plants don't seem to notice a difference.

Yeah, give it a shot. I'm just trying to direct all the light I can onto the plants. Looking at the walls of your boxes I see lots of light soaking into the brown cardboard...it seems like it would do more good/efficient for the light to reflect back to the plants, eh?

@Cam78 , I wanted to mention that a good way to test your lights for possibly being too hot on your plants is to hold the back of your hand three or four inches below the light. Gradually move it closer to feel the warmth coming off the tubes...a little warmth is good. You'll know if it's too hot and about how much distance you need between plant and lights. I shove mine almost right against the tubes...easily within an inch. The LEDs are much better than florescents in regards to having lower heat. I've had plants growing and touching the bulbs with no harm...but, use caution...YMMV.

The back of the hand is a good heat-sensor!

Ed it's LED. I was just surprised it's really warm on top. I can feel a little warmth with my hand above the plants. Problem is they are all different heights. Tallest ones have burn spots. Guess I should remove those and lower the light. I won't need 70 plants.

Any way to congregate the tall plants to one end of the light? Then you might could lower the other end of the light for the shorter plants???

Btw, you might not need 70 plants but having a large number to pick the best from is nice.

Ok I lowered it. I planted the seeds Jan. 27.
The brassicas I started outside last summer were leggy too. Didn't fertilize those seedlings though.

How long do you run your lights each day? I start might at 16 hours a day and that's where they stay as long as seedlings are beneath them. I use a cheap timer, one that has the little pegs in a circle that you push in or pull out to set the time you want the lights on or off. The old trailer is vacant and when I'm not actively growing seedlings I set the timer to turn on and off two or three times in the early morning and early night to make it appear someone is maybe living there or at least frequenting the trailer...a little security.

Seedlings *usually* get leggy due to seeking and *stretching" for more light. The more intense the light (without cooking the plants ), the better! Your daylight hours during February and March only ranges from a little over 10-1/2 hours to 12-1/2 hours...which might be why your seedlings in the sun last year got leggy. Also, at this time of the year the sun is still low on the horizon and the solar radiation is striking the earth at a low angle, not direct. The sixteen hours under the lights seem to work very well for me, other folks may do just as well with lesser hours, though. Your seedlings will love the higher light level...they should appear to stop growing as fast in regards to height and instead start getting a little thicker, stockier.

Looking at your light setup photo above, I'm wildly guessing that the light is roughly 5" above the seedlings. Moving the light to within an inch of the seedlings increased the light intensity hitting the leaves by a rough factor of 25. Not to shabby, eh?

Here's a little inverse-square calculator. Simply enter a power factor of "1" (leave quotation marks off) in the "Initial Radiation" box. Then enter your "Initial Distance" (starting distance) and then the "Final Distance" (final distance light is from the seedlings)...the calculator fills in the "Final Radiation" box for you. It is amazing the difference in energy that the seedlings remove by just this short adjustment! I entered 1 for initial radiation, 5 for the initial distance, and 1 for the final distance...
Inverse Square Calculator

Btw, hit the blue "Refresh" button at the bottom of the calculator to reset the calculator.
One thing to be aware of is that the "width" of the illumination will be narrowed as the light is brought closer to the seedlings. For a regular seeding tray another shop light beside your current one might be a good thing. So as to make sure the plants get equal amounts of both lights (if they're different) you could spin the trays weekly.

Now, after writing all of this, I gotta say I'm no genius and this is all just my comprehension of the inverse square law and how it affects growing seedlings. Hopefully some smart person will come along and correct any misconceptions or errors that I've made....hopefully!

Ok I probably need to have light on a couple more hours a day. The 2 broccoli varieties are the leggiest. I have a 1-3 inch height variation and the light is about an inch from the tallest plants now. I just rotated all the cells.