Far Red Spectrum 730nm?

[Hosebomber]

Well, neither really. It started with lighting for my wifes aquarium, that turned into her wanting to grow plants in the aquarium. That turned into aquaponics and then the lighting turned to terrestrial plants and not aquatic. Nearly 8 years and literally tens of thousands of dollars later, here we are. My engineering background probably helps a little but it isn't in electrical or lighting (although I have dealt with a number of electrical engineers). The biggest factor I believe is the internet. Nearly every advanced plant growth and lighting research ever done is available online and mostly for free now. So with a little patience and a lot of research anyone can have the knowledge that comes from a good education and more.

 

[CareStaker]

Bump.

 

[MaxBang]

730nm far red has some very unique aspects as to how these photo-receptors work. First, it can be used as part of the Emerson Effect. Secondly, the sole photo-receptor of chlorophyll F peaks very near this range (722 if i remember the article correct) and was only discovered a couple of years ago (2010).

As for the claim that it causes the Pfr to Pr switch to happen in seconds vise 2 hours... I'm not so sure about that. I find it very hard to believe. Far red and IR occur in nature. Adding additional lighting in that spectra will not cause it to do anything new, simply add the amount that occurs. The Pfr intake is what causes plants to stretch because they think they are being blocked out by near by plants. The claim of Pfr to Pr happening is seconds is correct. But I believe if they did actual studies they would see that the photo-chemical changes would still be active after the "5-10 minutes". There are a large number of studies on the Pfr to Pr and back to Pfr chemical transformation. FYI, 630nm red light is first transferred to Pfr before any other process of photosynthesis occurs.

For your second question, yes there are a few companies out there using far reds and near IR. According to their site, Advanced LED uses 720 and 740 (which is probably just a 730 that hits both).

but if you are growing indoors, don't you have to supply it in addition?

 

[Icemud]

but if you are growing indoors, don't you have to supply it in addition?

depends what you are using Far red for..... here are 3 common uses of far red, and whether or not you need additional 730nm far red.....


If you are using far red for the emerson effect: Most "white LEDS" 3k-6k, include Far Red in their spectrum, enough to take advantage of the emerson effect (enhanced photosynthesis), without the need for additional far red lights.... so for this, you would NOT need extra far red... many "blurple" LED lights also add far red, but not all so you would have to check. All HPS lights will put out far red naturally as well as most MH and CMH bulbs.

If you are using far red for "flower triggering" or "bloom boosting" as its commonly referred to, you WOULD need to add additional 730nm far red LED chips on a separate light and timer. For this typically you want the far red 730 LED's to come on a few minutes before your "lights out" and to remain on for about 15minutes to 30 minutes AFTER the "lights out" period. So for this use of far red, you would need a separate Far Red 730nm light with Zero other light spectrums, only far red.

Far Red also causes stretching in plants, so if you had some really short indica plants that were compacted, and wanted to them to grow more lanky, you could add some additional 730nm Far Red during your normal daylight cycle. The more Far red light to red light ratio, the more stretch your plants will have. So if you wanted to use Far red for stretching your plants, then yes, you would need to add additional 730nm far red.