Emerson Effect

[dalvis]

I was surprised that I didn’t find anything about this on the website, as it seems to be a new hot topic in other growing circles. Is anyone currently using far red light to create the “Emerson Effect”? It seems like using these can really help with photosynthesis but I can’t find a lot of information on WHEN to use it during the grow cycle. Using too much red can cause unwanted stretching and so there seems to be a limit.

I have some bloom initiator pucks coming in from RapidLED today that I will be hanging up tonight. My plan is to run these for the full 12 hour light cycle (as I’m in mid-late flower and don’t really think any more growth will occur) PLUS run them for 15 extra minutes after the lights go out to put my girls to sleep fast.

Anyways, has anyone used this technique at all? How did you use these lights and what results have you encountered?

Hopefully Nebula or someone can create an article on the website about this as well.

[DW2]

Howdy dalvis, I have never heard of the 'Emerson Effect' before, but I do understand the importance of the longer red spectrum's effect on plants (similar to early morning and late evening sun light). I'm not some botanist, it is what my first bubble phonic setup came with, A CFL lamp in the 2700° K spectrum and one in the 5000° K spectrum. The plants grow towards the bright white (5000° K) more than toward the shorter wave length red one (2700° K). This lighting setup has worked well for me in my DWC grows. At first there was one 55 watt lamp of each spectrum, but now, I have two each over each reservoir. It is not much wattage (220 total each reservoir), but I get good yields, The last grow of three plants gave me about 14.69 ounces total of bud!

[dalvis]

Definitely check it out! Just google “Emerson Effect”. It was research done back in the 50s that has just sat dormant. The idea is introducing non-Photosynthetic spectrums that work along with your normal photosynthetic spectrums to increase plant mass. Also, using the far red for a few minutes after lights out put your plants to sleep almost immediately (opposed to the 2 hours it takes by just going lights out).

Bruce Bugbee out at Utah State (has license to study cannabis) has been recently studying this phenomenon and seems to think it is a very useful tool.

[DW2]

dalvis, thanks for the information! I'll check it out.

[ChadWestport]

The Emerson effect is taking advantage of both the PS1 and PS2 receptors (photosystem 1 & 2) both of which harness light at different wavelengths. Its basic principle is that it uses both the short and long wavelength in combination to increase photosynthesis compared to an individual wavelength.

[dalvis]

The Emerson effect is taking advantage of both the PS1 and PS2 receptors (photosystem 1 & 2) both of which harness light at different wavelengths. Its basic principle is that it uses both the short and long wavelength in combination to increase photosynthesis compared to an individual wavelength.

Not sure if this was meant for me or everyone else, but I know what the Emerson Effect is, I just wanted to see how everyone is doing it. Are y’all running the far red 12 hours a day or less? Are y’all using the far red during veg and flower or just flower? I’m always down to experiment but if I can learn from others even better.

[ChadWestport]

Some LED lights will have a few of these lights built in. You don't really need a large wattage for it to have an effect. One of the more common uses I have heard (but not tried myself) is to use the Emerson effect to put the plants to sleep faster.

From a different forum, not a scientific paper -

If you give the plant 730nm far red for 15 minutes after lights out, all the phyotochrome switches to its inactive state in 15 minutes instead of two hours, effectively lengthening your dark period and speeding up the flowering process.

This however I don't think would be too effective with an auto plant because it couldn't care less about light / dark, day / night.

[dalvis]

ChadWestport I think I need to correct you there (or at least correct that forum post). What your quote described was “bloom initiation” and not the Emerson Effect. Yes it is true that subjecting your plants to far red after lights out will put them to sleep faster (hence “initiating” bloom), the Emerson Effect has to do with having far red on for longer periods of time to work in conjunction with the more photosynthetic wave lengths to increase plant growth (~10%). My original post was to try to see if anyone has used this and seen results with x hours of far red exposure plus any growth notes on effects during veg and/or flower stage.

And yeah I agree that they do not need to be intense lights to produce this effect. I have two of these from RapidLED that draw about 6W each. Hanging them up as soon as I’m done with this post and plan to run them on the first 3 hours of lights on then the last 3 hours of light +15 minutes. We will see.