Growing some sativas in RDWC. Discovered this deficiency today, looks like it’s probably pretty easy to identify to someone who knows what they’re looking at… some info about the grow:
Ph: 5.7 upon discovery. It’s been at 5.8 last day or so.
PPM: 470
Water temp: 68
Nutes: GH flora trio, rapidstart, CaliMagic, Armor Si, Floralicious
This is mid-week 3 of the grow. What I do know is that it’s a mobile deficiency, being that the lower part of the plant is most affected. Yellowing at the ends of the leaves, which start to show brownish purplish blotches after a bit. Newer growth at the top has not been affected yet. Not any noticeable drooping, growth seems ok not too stunted. Also no curling as of yet.
Something tells me it’s in the potassium or magnesium realm bc I know too much or not enough of one can lock out the other. What do yall think?
Kind of seem low on the ppm side for the size. I don’t use the trio though so maybe that is where they say to have it I only used Bloom and Micro for the entire grow with the GH Lucas formula then moved to Jacks 321 but running 4:2. Around this time with the lucas form I was in the 500-600’s and with jacks I stay at 850 from start to finish.
As for pH you can get away with as low as 5.5 but really want to stay in the 5.8-6.0 range.
If interested in the Lucas Formula here is a good link
I might consider upping the ppm. I’m somewhat of a newbie so I might be wrong, but I’ve been under the impression that a hungry plant is usually a nitrogen deficiency in veg. Either that or ppm dropping, but neither of those things have happened I think so I haven’t considered the PPM levels.
The other thing I was thinking was maybe epsom salt? From my homework, K-Ca-Mg should be 4:2:1, and my current feedings mg is a little low so that’s part of why I figured Mg def
I used only Bloom/Micro and didn’t really get any deficiencies until my light was on too powerful or close late in flower. Now I did put in calmag from the start, I think 3-5ml/gal. I’ve never used Epsom so can’t help there but some do when their lights are hitting hard and causing the plant to use a lot of Mg. Which I think was my case during flower but got solved when switching to jacks ferts.
