Some observations of germinating seeds and growing seedlings under LED

[nullzero]

I have been using LED grow lights for a couple years now. Usually I have used them to germinate some seedlings indoors. In the past the quality and intensity of the LED lights has been on the lower side. This year I bought a Mars Hydro 300w (140W true watt) LED light. It was recommend to have it for a 2x2 area for vegetative growth. So I purchased a 2'x2'x3' mylar grow tent and placed the Light above at about 2' 8" above the floor of the tent.

I have used lower powered LED UFOs, and found this one to be quite a bit brighter. The good thing was that the light for the are was more then adequate enough. The bad part was it was so bright for certain plants it caused bleaching of the leaves (white and clear new leaf growth). The leaves of certain seedlings were being over saturated with bright light.

From observations some seedlings did not mind the bright intense light. Nara Melon (Acanthosicyos horridus), most cacti seemed to really enjoy it and thrive with the light. Things like Coinosicys macranthus not so much, I actually had to move it to another area with a less intense light to renew its green growth. Myrciaria phitrantha seedlings have been a surprise and handle the bright light quite well. Garcinia sopsopia another one that handles bright light well as a seedling. In the end, it makes sense having separate grow tent/areas which have varying amounts of light intensity and humidity for germinating and nursing seedlings. Also it helps to be aware of the nature habitat of the plant to provide optimal light.

[FlyingFoxFruits]

Thanks for sharing Nullz!

Plants look extremely happy!

[Vernmented]

Very interesting. Thanks for sharing. I love these super intensive posts. I was looking at LED lights this summer and the quality is really going up and the prices coming down. Really wide spectrum lighting with switchable veg and flower. They booming pot industry is bringing some nice technology and innovation to us tropical fruit enthusiasts. There is some great information on the "weed boards."  The NSA probably thinks I have a drug lab in my house between that and the mushroom growing info. 

[nullzero]

Thanks for sharing Nullz!

Plants look extremely happy!

Thanks, I like to report Eugenia selloi does well in this setup. It seems to be another seedling that can handle brighter light. I am most impressed with Acanthosicyos horridus under LED, its starting to really branch out in all directions. Its double the size from this last picture 11 days ago. Parkia biglobosa seedlings were a little stressed with the intense light, I moved them back into a lower LED light intensity ( think it will be able to handle higher light intensity after it gains some size).

[fsanchez2002]

Thanks for sharing Nullz!

Plants look extremely happy!

Thanks, I like to report Eugenia selloi does well in this setup. It seems to be another seedling that can handle brighter light. I am most impressed with Acanthosicyos horridus under LED, its starting to really branch out in all directions. Its double the size from this last picture 11 days ago. Parkia biglobosa seedlings were a little stressed with the intense light, I moved them back into a lower LED light intensity ( think it will be able to handle higher light intensity after it gains some size).

Let me ask a (maybe) stupid question: can LED help seeds germinate faster (i.e. do seeds buried in the ground with no growth yet sprout faster under LED)?

[nullzero]

Thanks for sharing Nullz!

Plants look extremely happy!

Thanks, I like to report Eugenia selloi does well in this setup. It seems to be another seedling that can handle brighter light. I am most impressed with Acanthosicyos horridus under LED, its starting to really branch out in all directions. Its double the size from this last picture 11 days ago. Parkia biglobosa seedlings were a little stressed with the intense light, I moved them back into a lower LED light intensity ( think it will be able to handle higher light intensity after it gains some size).

Let me ask a (maybe) stupid question: can LED help seeds germinate faster (i.e. do seeds buried in the ground with no growth yet sprout faster under LED)?

Yes it makes things germinate much faster, especially if their is any type of light requirement for initial germination. I get fast and good successful germinating with cacti seeds. Things like Nara Melon have not germinated for over a month in lower light situation, once they were under the brighter LED light they germinated in a matter of a week.

I also use clear water bottles with the tops cut off for germinating containers. I find that it does not effect roots much at all and increase germinating due to the light bouncing from the sides of container. Plinia sp. seem to germinate a lot faster with the light. Temps are ranging between high 60s at the lowest point with the light off in the early morning to 85f during the warmest part of the night. Humidity around 50-70%.

[pitbull-rus]

Only red light stimulates germination.This has been proven.

[nullzero]

Only red light stimulates germination.This has been proven.

I was commenting on the germination increasing with the brighter light. I think it has to do with the better light penetration below the soil cover and hitting the seeds.

[mangomike]

"Let me ask a (maybe) stupid question: can LED help seeds germinate faster (i.e. do seeds buried in the ground with no growth yet sprout faster under LED)?"

Many species have seeds that require bright light for germination. Many California natives, for example, will not germinate until brush fires burn off the chaparral allowing light to reach the soil. Tobacco species are another example.

[SoCal2warm]

Mangosteen seedlings, lychee, rare citron variety seedlings. The big one is a mangosteen.