Grow lights -- what do you use; are you happy with them?

[Sue_CT]

Thank you and thank you again for the detailed instructions for rewiring the ones I have. I just don't have the ambition to figure out how to rewire them, even with your detailed instructions and then search out the proper lights. I am generally a dedicated do it yourselfer, but I have enough back log of projects and don't love electrical work, or feel comfortable with it.
Thank you for taking the time to post all those instructions, though, I am sure others will find them very useful.

[HL2601]

Thanks for starting this thread Sue. I am getting ready to make a second set up so this is really timely. Squibb-all that info and your pictures are much appreciated! Your set up is awesome!

[Sue_CT]

oops,can't take credit for starting this thread, that was Greatgardens. I chimed in becauseI also need to improve mine.

[IndoorGrower]

Sue, I'm currently growing seedlings under "plug and play" shop lights that look very similar to the ones you posted.

They were available at Costco for $17.99 after a $10 "coupon." They go on sale every few months or so. My tomato seedlings seem to be doing great positioned 1 inch under the tubes. The lights only heat up to around 80 degrees F, so I'm comfortable with having the light so close to the plants. (My ambient room temperature is around 68 degrees F)

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[Sue_CT]

Thank you, I will look at those, too.

[pepperhead212]

I use old shop light fixtures in my seedlings shop, but I replaced the ballasts with digital ballasts, and higher output (3,240 lumens) 5,000k T8 bulbs. For the hydroponics I have two of those in the center, and a 5,000k T5 bulb (5,200 lumens) on both sides. These are just herbs and greens - no flowering plants. Just this last year, Harbor Freight came out with a really cheap LED shop light - 1 bulb, 5,000k 5,000 lumens, and supposedly 30,000 hours, for $19.95 each (I actually got them for $16.95 each). Here are the lights, at regular price, but they are always on sale with a coupon:
https://www.harborfreight.com/4-Ft-LED- ... 64410.html

I tried a few tomatoes under two of them, and they grew as fast and large as those under the 4 florescents, but got purple tints under some of the leaves. That didn't seem to bother the plants, as noted on another thread.

[SQWIB]

Try to get a higher K rating 6000k is perfect for seed starts, any will work but you will be much happier with the results of a higher Kelvin LED

[Sue_CT]

Thanks, SQUIB, I was wondering about that.

[pepperhead212]

SQUIB, When I got all those 5,000k "daylight" bulbs, the 6,500k bulbs were 700 lumens lower than the daylight bulbs - 2,700, vs. 3,400 - and ones I see in local stores are also much lower than the daylight bulbs that they sell. And the daylight bulbs also had a much higher expected lifetime, around 34,000 hours, compared to 18,000. I have had no problems with seedlings, or the hydroponics, when using these for vegetative growth.

[Sue_CT]

Is there any advantage to "Daylight" vs "Cool White" lights?

[pepperhead212]

Daylight bulbs are a higher kelvin, which is slightly better for seedlings, and vegetative growth.

[SQWIB]

Just lost my very well thought out post and I'm not retyping it.
Cool, warm, daylight is all subjective.
Go by Kelvin, the higher the better.
Daylight would be the highest Kevin out of the three (descriptive) bulbs and I have seen manufacture's with cool being close to daylight in Kelvin so it's at the manufacture's discretion what to call it, however Kelvin is not subjective and is a better way at determining color temperature (Kelvin).

[Sue_CT]

Great, thanks. The lights I am looking at that I posted above are 6000k. Sadly, they will not last very long. Assuming they last the 5000 hours that they claim, since I leave them on 18 hours a day for 8-12 weeks, they will only likely last for 3 years. They do have a 5 year waranty, but not sure simply burning them out would qualify for replacement.

[Gthegardener]

I’ve been using these LED 19W full spectrum grow lights from Home Depot (best deal since they price match online). I had great success with them last year and the price is really good.

https://www.homedepot.com/p/Feit-Electr ... /302049784

[SQWIB]

SQUIB, When I got all those 5,000k "daylight" bulbs, the 6,500k bulbs were 700 lumens lower than the daylight bulbs - 2,700, vs. 3,400 - and ones I see in local stores are also much lower than the daylight bulbs that they sell. And the daylight bulbs also had a much higher expected lifetime, around 34,000 hours, compared to 18,000. I have had no problems with seedlings, or the hydroponics, when using these for vegetative growth.

That's the trade off. I do believe that the higher Kelvin may appear brighter than it really is and the most accurate way to determine which is putting out more light is by the lumens but it's not quite that simple.

For you the better choice was the 5000k.
I would have sacrificed the lower lumens for the higher Kelvin but that's me.
I was sold on higher Kelvin after my lettuce test I ran last year.
Either one you have mentioned is a great choice, you can't go wrong.
Not to get too technical but lumens is the light output that is visible to the human eye. And it's measured at the source.

Lux is determined by distance and decreases and increases by moving the light closer and further away.

Par (photosynthetic active radiation) is the light radiation the plants see, for instance we can't see infra red but plants can use infra red.
So higher lumens don't always mean more light for the plants.

Lumens is for humans and Par is for plants.

Pepperhead, here is a website that explains it better than me, I'm a novice at this light stuff!
https://www.thcfarmer.com/threads/lumen ... nfo.37783/

Sorry I babbled on so much.

[Sue_CT]

Those HD lights are twice the price of the ones I have been using and the ones I am looking at. They might be worth it, but I would need 8 of them, at a cost of 320.00. I have been using 4 4ft long lights with 2 bulbs in each light, so I would need 8 lights that are only 2ft long.

[pepperhead212]

That was a good, though lengthy article, with a lot of the info on lights I got in articles in a hydroponics mag years ago. It reminded me of another thing that was better on that 5,000k bulb I chose - the CRI, which was 91, vs. 87, for the 6,500k. It's hard to weigh all the different things with the lighting, these days, and there are so many more of them, than back then. I'm just glad I'm only trying to grow herbs and seedlings - I don't try to grow flowering plants indoors, which needs totally different lights.

[davidjrtx]

I use floresent on a shelve but once they come up move them to sunshine or pink grow lights

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[SQWIB]

That was a good, though lengthy article, with a lot of the info on lights I got in articles in a hydroponics mag years ago. It reminded me of another thing that was better on that 5,000k bulb I chose - the CRI, which was 91, vs. 87, for the 6,500k. It's hard to weigh all the different things with the lighting, these days, and there are so many more of them, than back then. I'm just glad I'm only trying to grow herbs and seedlings - I don't try to grow flowering plants indoors, which needs totally different lights.

I was going to mention Color rendering index but figure I babbled too much already, but since you brought it up, lol.

I looked into high CRI 93 for lighting in my dining area because it is all cherry wood. The higher CRI brings out the true beauty of wood.
It's also preferable for photography, museums like displaying art and for color matching with printing.
It's funny but I tell people when they go to paint a room to install their lights first especially if using LED's and that CRI is important, they could paint a room, change out the lights and say what the heck happened to the paint

Bathrooms I go higher kelvin as I do in my workshop, its a harsher light and looks like a lab. For my living area, I try to go with dimmable 3000k. Higher CRI weren't available then so I think they're only 80
My dining room is all cherry so I also went low kelvin and a higher CRI, IIRC.

You also have full spectrum (band) to confuse things even more, on my Viparspectra's, I have 12 band some are IR and some are 3000k and 7500k and 440nm - 730nm which is IR.
Typically, the human eye can detect wavelengths from 380 to 700 nanometers. But now they are saying we can see up to 740nm and some articles say up to 780nm

So a light may seem brighter to us but how much of that is the plant using?

OK, I'll stop babbling and put up a pic, and for anyone following, everything that has been posted thus far will work for seedlings so don't get overwhelmed with all the science. This is just some friendly banter for those that are curious about true light output for plants not humans.



Further reading about Photosynthetic pigments if you are interested,
https://www.khanacademy.org/science/bio ... c-pigments




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[SQWIB]

I use floresent on a shelve but once they come up move them to sunshine or pink grow lights




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Wow, that is an impressive setup.