Grow Lights


It doesn’t look like there’s a general grow lights topic, so here goes. I have a couple T5s that I like. I use them to keep peppers and guavas alive during the winter. Also for seed starting and for some potted persimmons and figs that might wake up too early. But I’m wondering if any grow lights, maybe LEDs, can help ease the transition from indoor growing to outdoor growing without the need to gradually harden off plants first.


I use T12 shop lights. No experience with LEDs, sorry. I keep the potted lemon and clemintine under the lights in the winter and use another light fixture to start seeds. Has worked well so far.


I’ve used 4ft long T8 bulbs in a 4 bulb fixture that I hang from chains in the hallway. I just use them for my tomato, pepper and herb seedlings in the spring after they sprout. I’ve used them the last 3 years and my seedlings love it. Don’t have any experience with LED lights tho.

Imo, I don’t think there’s any indoor light that would take the place of hardening off plants.

@thepodpiper and @Drew51 could maybe offer some insights, they grow a lot more stuff indoors than I do.


Hardening off involves not just light but temperature and wind, as well - going from a controlled environment to an uncontrolled one


Nothing replaces outside, You could add fans to get thicker stalks on say tomatoes. I only use lights when i have to. LEDs could give them more light, i suspect better LEDs for plants will be developed, most lack or have low output of needed frequencies. For short term it doesn’t matter. The next up from T-8’s is T-5’s a 4 bulb, 4 foot bulb fixture works well, and will help. Although LED looks promising, and less power to run. T-5’s suck power and you will notice it on your electric bill.My hemp growing friends all use halogen lights. You have to grow hemp to pay the electric bill! Acclimation to just air movement is needed, so I can’t help much on how to eliminate, although fans and stronger lights do help.


i have a friend who is in the medical canabis industry. they use high output leds but they aren’t cheap but you can get a decent one thats a lot better than fluorescents for about $200 that will last a long time. amazon has all kinds.


Led is cutting edge right now and they aren’t to hard to diy build. Here are some off my indoor plants right now. All under lights i build myself.


nice setup! wish i was any good with electric. those cobs look nice!


Watch this video. There’s a really big difference in led’s.

Platinum led’s



I agree, why I was hesitant to buy any, the Platinum looks awesome. As I mentioned spectral range is a huge problem with LED’s This seems to have solved that. Expensive though, but the saving in electricity actually make it cheap.


I researched them pretty heavily. I spent like a whole day one time.

Drew, mine I did the math and it costs 5$ a month to run. I have a Platinum 300w.



The review says that one has 4.5ft x 3.8ft coverage at 18" height. Do you find that to be pretty accurate, Dax? I’ve been looking at that one and the AdvancedLED Diamond series light.


I keep it pretty high above my plants. I think mine is more like 3’ above. I did refer to the owners manual. I probably should lower it now thinking about it. I started cuttings using that “toothpick technique” I posted about and for the first few weeks or something you’re supposed to keep the light higher. After that you’re supposed to lower it. I never thought about lowering it.

But yes the area of coverage they say is good. I started seedlings last year and it just blew my shop ballasts I converted for led’s away.



I built a rectangle and hung it from my basement rafters. I just went and measured and my rectangle is 44" x 27". Then I used reflective insulation for a base sitting on wooden boxes. I must’ve taped two pieces of reflective insulation to the diameter of the box as the mylar hangs down from the frame and keeps the walls perfectly level side to side & up and down. It’s probably the same coverage you asked about or something close to that I just came up.

Of course I used simple hardware. Eye screws to clip the light onto, for example. Easy stuff ya know.



I think my VHO T-5’s cost at least 20 bucks a month or maybe it’s 30? I’ll wait till my ballasts go bad. One did and what a pain replacing it!


Yeah, big time. I actually made a youtube video with an easier ballast to re-wire. The old time ballasts are a freaking nightmare as are the ones that walmart carries (their cheapest.) For another 5-bucks or something I bought shop ballasts from Lowes and while it takes time, it’s so much easier.



I use a much cheaper LED set — I bought it last year and used for tomato seedlings. Outdoor hardening is still needed. Tomatoes are the only plants I start inside the house. I root all cuttings (figs, pomegranates, etc.) outdoors as temps rarely go below freezing in my area.


Last year my husband installed a 2 strip set of LED lights over the front bench in our attached greenhouse. They’re just regular LED’s lights (except they happen to be 12v), mix of bright white and warm white. I’m not trying to grow anything exotic, just wanted to extend our short days, short sun period to help the greens grow, and allow starting seedlings earlier. Didn’t know how it would work but he had some sets leftover from making house lights so we thought we’d give it a try. They worked well and use little power (important to us as we produce our own power) (solar). I’m real happy with them. The lettuce and other greens were the healthiest I’ve had and they grew better. So did some early seeding I did. Now I have on my wish-list a similar set over the bed along the back side of the GH.


(more info and photos on the lights in the GH at

Steven, as others have mentioned I don’t think lights will help in hardening off. I used to haul things in and out of the greenhouse getting them used to the outdoors, but now I simply transplant on a cloudy day (usually enough of those here) and cover with sheets (or something) during the sunniest part of the days until they seem acclimated. Tender crops go in cold frames, similarly covered. It’s worked well for me and is a lot easier.


Hello @Stan,

The “spectral analysis” on your 80$ light looks pretty good! It’s opposite mine on the blue and red scale but I don’t know anything about that really. I’d say you got a hell of a deal. You look at the ‘Mars’ lights for more money than your light and their spectral analysis is pretty well junk. That’s what you’ll find on ebay day in and day out.

Anyway, my buddy proposed I grow his garden vegetable plants and for two of his friends and said they spend hundreds of dollars buying them online and would pay me the same price if I grew them. And my light is made in the USA. Maybe yours is… I don’t know. But, that is a selling point for me.


I’d been debating hanging lights in my greenhouse like that for years. It’s perfect for what you’re mainly doing. I was going to do it for grafted conifers years ago. That’s perfect what you have going there.



yeah. i heard the platinum are top shelf leds. hopefully the price comes down more as they get better over time. got a spare bedroom id love to grow in during winter.