LED grow lights

[whimsicaldrift]

Am somewhat of a new gardener, but I've been considering investing in some LED grow lights. Not being particularly handy, I've been looking online - ebay scared me, so I came running here for advice!

I just wanted to ask if anyone here has any input on how effective they are; if there's really a difference between the red-blue lights and the red-blue-orange-white lights..? Also any recommendations/reputable sellers would be amazingly helpful... well, or warnings not to buy from certain disreputable sellers would be great too!

[Redbaron]

I think LED grow lights are a scam in the first place. Maybe someone else has a better recommendation about them, but I sure don't.

For starts florescent are OK so I suppose LED could be too for starts, but that's just temporary. For the whole season I wouldn't use anything but metal halides and high pressure sodiums. Only thing I ever got to work decently unless I also had some other way, like a window, to get sun too.

To be honest I don't use lights anymore, I did years ago. I just build a small coldframe for starts and grow everything outside now.

[Worth1]

I tried to do a little research for you but got inundated by too much garbage on the internet.
Most selling grow lights.
For many years now I have used florescent GE bright daylight lights.
As many lumens as possible.
I keep the lights as close to the plants as possible.
After a year they go in my kitchen.
On florescent lights the standard is 40 watts per square foot.

I have never had a problem with elongated growth.

I have yet to experiment with LED lights because they are too expensive.
Just like everything else the price will go down somewhat, but not a lot.
Reason, they are cheap to make but they last so long.
LED light is nothing new, it was discovered back at the turn of the century.

Worth

[OddBall]

In 2010 I have visited the hortifair in the Netherlands, one of the booths was for Philips lighting and they were showing their LED grow lights, the line is called GreenPower LED.

We haven't tired them our self, but one lettuce producer at the fair said they are using them already, and they are having good results.

[Darren Abbey]

Many of the LED grow-lights around basically have red and green light tuned to the highest absorption peaks of chlorophyll. There are two difficulties with this design principle.

The peaks are defined for chlorophyll isolated from plants. In plants, there are various accessory compounds which may alter the exact frequency of best absorbance. This may lead to the extremely narrow-frequency LEDs being sufficiently off-target for your particular plant.

The second is that plants use other frequencies for developmental reasons, which will not be captured with the LEDs. What triggers compact growth or sparse growth is not necessarily chlorophyll absorption. (I've even seen this problem with fluorescent tube grow-lights. Some plants like them just fine, others would grow etiolated no matter how intense the light.)

For both of these concerns, you would have to test the LEDs you have against the plants you want to grow. If the plants you grow like the LED lights you have, then it just an issue of sufficient lumens/cost, which is where LED lights definitely do well.

[ContainerTed]

Lowes sells a florescent fixture for two T-12 bulbs (4 feet long) for about $13. They also sell a box of 10 6400K bulbs for about $28. These daylight bulbs are cheap to buy and cheap to run. They also have all the frequencies that the plants need.

I have 10 of these fixtures now and will add a few more for next year. For ease of operation, and ease of cost, them folks can keep their expensive LED's.

[neoguy]

Originally Posted by ContainerTed

Lowes sells a florescent fixture for two T-12 bulbs (4 feet long) for about $13. They also sell a box of 10 6400K bulbs for about $28. These daylight bulbs are cheap to buy and cheap to run. They also have all the frequencies that the plants need.

I have 10 of these fixtures now and will add a few more for next year. For ease of operation, and ease of cost, them folks can keep their expensive LED's.

The T-12 fixtures have been discontinued, once the supplier runs out of fixtures and bulbs, you're out of luck. Don't buy the fixtures, period!

Look into T-8 or T-5 Fixtures.

I'm in the same boat.

[whimsicaldrift]

Thank you for all the advice, looks like I'll have to re-think the LED decision... am glad I stopped by the forum before I invested in the lights.

[bower]

I got the T-8's last year, they were phasing out the T-12s then. The new fixtures for T-8s are more energy efficient, so you may not save anything by hunting down old ones either. In any case the fixtures are inexpensive.

The fluorescents worked great for starting seedlings and for growing greens, with the lights kept close above the plants.
I also installed them in my windows as supplementary lights for some big pepper and tomato plants to overwinter. They saved me money on lighting, since they are plenty bright, and I just stopped using the overhead lights and found it was cheaper as well as better lit.
I got some different bulbs to experiment with temperature colour. They say that the yellow/red end of the spectrum (lower colour temp) is best for flowering/fruiting and ripening, while the blue end (higher colour temp) is best for vegetative growth. Others have commented that "cool white" is just fine for most purposes, middle of the road and less expensive, and I think that was true. "Daylight" is very blue and dramatic to me but not really different to the seedlings, cw 'cool white'. The 'warm white' is more like incandescent bulb colour.
The warm white colour was great for ripening fruit already on my pepper plants, and you could see the fruit get red first on the side closest to the light. It didn't stop the peppers from dropping blossoms all winter though. They didn't start to set new fruit until the return of 10 hours of actual daylight. So in the dark days of winter, the extra hours of light from the fluorescent was not enough to fool them. This is why serious indoor growers use HPS and halogens for big plants - expensive to buy and costly to run as well. They aren't necessary for seedling starts or greens which do just fine kept close to the fluorescent lights.

[RayR]

Originally Posted by neoguy

The T-12 fixtures have been discontinued, once the supplier runs out of fixtures and bulbs, you're out of luck. Don't buy the fixtures, period!

Look into T-8 or T-5 Fixtures.

I'm in the same boat.

Afraid you're right about the T12's, it's getting harder to find the GE Daylight 40 T12 bulbs I like for their 6500K, 3050 Lumens. Fortunately the American Florescent Shop Light fixtures I bought a few years ago support both T12's and T8's, so I can still buy the GE Daylight 32 T8 bulbs at 6500K/2700 Lumens. Still decent for growing transplants.

I think LED's have a way to go in cost/benefit before I would consider them.
I would rather get a really nice High Output T5 setup if I was going to spend that kind of money.

I'm using a couple of old recycled T12 fixtures with the magnetic ballast. The newer fixtures use electronic ballast and generate a lot less heat which probably means even lower energy consumption. If the newer fixtures emit the same lumens as the old T12's, they should work great. I germinate all my tomatoes under the lights and with the exception of when I harden them off, they stay under the lights until plant out. I've never had a problem with them and can't think of any reason to change.

I start my seedlings about two inches below the lights and lower the table to about twenty four inches as they grow. The plants always stay within two inches of the lights. With the exception of the light tubes, everything is home made or recycled so it cost almost nothing.

If your interested in a do-it-yourself project, check out the recycled building materials shops. I always see a lot of the fixtures at the Habitat For Humanity resale shop. I assume they are located everywhere. Use your imagination on how to support the fixtures and build a table. It was fun.

Ted