LED light issues with plants

So thats what I could be doing with all my mcdonalds cups!

That depends on the wattage. I have a very cheap red/blue LED array that is under 100 watts. My pepper are and tomato seedlings are 1 inch from the LEDs. Because the wattage is low there is no noticeable heat and because the small seedlings are so close they get plenty of light. Once the seedlings are 5 to 6 inches high they no longer get enough light and I move them.

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LOL! Hey I’m not allowed soda anymore, so I reuse them! Mctree pots!

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another toy of mine

2 story grow box. Beets in my dirt basement floor and citrus trees in the warm 2nd floor. The heat from the beet lights heat the floor of the citrus area.

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my pot growing buddy would be very impressed! :wink:

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Ya know i think you guys should only buy leds that use the industry standard rating of j/w or atleast put out a ppfd or umol rating for the fixture. If they do not do this they are being disingenuous. A new t5 bulb produces 1.8j/w so that is the minimum for buying a led imo. Also you want the white with a few red and maybe blue or uv diodes. There are some of the blurple lights that work but usually those are for greenhouses as a supplemental spectrum and they have been replaced.

I do not think most of those cheaper china leds they are selling online are really for growing medicinal cannabis. Gavita and phillips have that locked down for the ag industry. However they work great for everyone heres purposes as long as they are above that 1.8j/w rating your saving electricity. The good leds can be placed 6" from plants with umol ratings over 1400 and not burn them.

@Bart Sadly i think you need to add in some t5 or natural sunlight to fix your issue as i believe it is caused by your lights. I am not saying plants will not grow with these but i am saying they may grow better with t5s

I just bought 2 of those cheep Chinese models and a LUX meter. Don’t actually know what a LUX is but I was hoping someone could tell me how to do some rudementy testing to figure out if the output is anything like what’s advertised. I also have a Kill a watt for measuring power consumption.

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the kill a watt is a great detective and will tell you how much power you are actually using. What lux meter do you have, some are decent some are not. They really do not measure usable light by plants and are just not a great meter on grow lights in general and more made for the sun. The $20 analog solar powered footcandle readers are better imo and usually you are going for the 3k on those (or 30k lux). I think seedlings are happy down to 1k Foot candles or 10k lux. Lux is 10x footcandles and because its based upon the human eye and not plants the industry has moved to umol for a better reading of what the light is doing.

mine are the mid priced blurple lights. i figure if i can grow 4 weed plants to 6ft and to flower only on organic amendments under those 2 lights i can grow anything with them. if i have growing issues its usually p.h, ferts. or watering issues. ive had mature plants grow right into my lights before i see bleaching on the top leaves but seedlings are more sensitive. these lights have come a long way in 20yrs. t5 are great for seedlings as they cover a bigger area so you can put more under them. if i was just doing seedlings id go that route. not as energy efficient as the better leds but if your just starting seedlings and growing some lettuce and such, they do a great job.

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