Article about horticultural LEDs

[naoki]

Just in case you are interested, LEDs Magazine has an article about horticultural LEDs. It is relatively light in contents (not much technical aspects). We, DIY LED people, have been pushing white LEDs over the older concept of red+blue based fixtures for a couple years, and the grow light industry is also following this trend as the article points out.

http://www.ledsmagazine.com/article...hing-led-lighting-to-horticultural-needs.html

There are lots of cool products this year for DIY crowds, and I have a couple Samsung and Citizen LEDs waiting for the assembly. Hopefully, I have time to post about these money-saving LEDs in the next month or so.

 

[suzyquec]

Thank you for this post. I use LED's heavily and have been slowly incorporating the "Full Spectrum" that includes the white. I have 2 full spectrum now and I am anxious to see if there is a difference to my older LEDs. I have separated Phrag and Paph babies from the same flasks and distributed them under the 2 different forms of LED to see if there is a difference.

 

[naoki]

Suzy, it will be interesting to see how they are different!

Light spectrum would influence the orchids (Phals and Oncidium), but there are only a few experiments, and many of them are using growth in flask, which is different from the adult environment where photosynthesis is the main driver. One experiment using adults showed that chemical composition can be influenced by blue dominated light (more production of chemicals against pathogens). My anecdotal experience is that leaves seem to express more red color with R+B dominated light. But I didn't control the intensity etc, so it could be simply due to the difference in the intensity.

 

[eteson]

Thanks a lot Naoki. Very interesting.

 

[abax]

Excellent info., Naoki. Thank you.

 

[Ray]

A great article, Naoki. Thanks for sharing.

 

[naoki]

Similar to how people are trying to produce yummier, nicer-looking lettuce and tomatoes by modifying the spectra, I wonder if orchid people would be using similar techniques to get the awards in the future. After all, flower parts are modified leaves developmentally, so they might respond to different spectra. On the other hand, the functions are different: light capture of leaves vs pollinator attraction of flowers. Leaves respond to the spectra in terms of expansion rate/size or color because they want to optimize the light capture while flowers may not care about the light quality. Interesting to think about, but I haven't found any literatures about effect of light quality on flower size/shape/color.

As a more technical side, while white LEDs are cost effective at this moment (due to the rapid development driven by light bulbs), Cree and Philips are making gradual progress in monochromatic LEDs. According to this page, Cree has increased the efficiency of XP-E and XQ-E red/photo red. It will be interesting to compare it to Osram Oslon Hyper Red 660nm. Philips has developed interesting purple LEDs, too (here).