G
Guest
Since I started adding some Epsom in flower a couple times in water I noticed a big diff myself. Plus I also add some BioMin calcium.
Ok so I’ve been testing a little. Foliar only.
CalMag+ (4-0-0 with Fe, Zn and Mn) doesn’t make much of a difference to be honest. Applied at 2ml / L as recommended on the label. Maybe I should have added more. Maybe I still will. After 3 days there was no visible change.
Epsom does better in my case. I started at 1g / L at start of veg but when the plants got bigger it didn’t cut it anymore. I’ve upped the dosage to 2g / L with immediate results again.
Then I raised the power to 50% at 30cm height (~500 PPFD). The 2g / L epsom wasnt enough to keep up with the vigor. I’m at 3g / L now in order to keep the vigor and no fading on new fan leaves growth.
I spray every 2 or 3 days to keep up with the metabolism.
My temps have also raised from 24 to 28-29C (with 70-75% rH).
More PPFD and higher temps raised the demand for Mg dramatically.
This is crazy.
I have been using epsom salts with a mg conc. of 10-15ppm target. Saw very moderate results after two sprays. Then mg def. came back, gave some more mgso4 sprays, but got a Ca def. and had to hook up my dehumidifer (lol)/ tried a CaNO3 spray. Im thinking of making a CaNO3 +MgNO3 spray. We'll see how it goes. Problems really came out for me once the plants got biiigg.
I’ve done some reading. Looks like the usual white LED spectrum makes the plant put most of the work load on two specific pigments that process the light. These are chlorophyl a & chlorophyl b.
Plants under HID sources and sun use plenty of other pigments to metabolize the spectrum of such light. Others being Carotene, Xanthophyll,
Phaeophytin a, Phaeophytin b.
Chlorophyl a and b are based on Mg, hence the increased demand for Mg as these pigments carry most of the work.
Chlorophyll a absorbs wavelength of 400–450 nm and 650–700 nm
Chlorophyll b 450–500 nm and 600–650 nm.
No because many blurples put out more red and blue and especially red. I do't have any of these issues with blurples.
I bought an infrared thermometer to measure LST.
Another organic, quantum run started. Early flower classic magnesium def symptoms again. Light green chevrons, interveinal chlorosis.
Current environment is 78F/55% daytime. 70F/63% nighttime. Going to try and get about 5F more during daytime. Either by bumping power, moving drivers inside tent, adding one more light or a combo of the above. Everything I've seen says run +5-9F.
We shall see.