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Possible N deficiency?

afman916

Member
Admittedly not as often as I should - since all of my inputs are organic as far as I know, I was under the impression more can’t hurt TOO much since soil buffers...but in reading that as I type it out, I realize it’s probably the opposite.

I’ll make sure I do plain water every other from now on.
 
EC is high. Sativas are usually lighter feeders compared to indicas. Your plants definitely looked yellowed but not burnt. So either nutrient starved or ph imbalance. Also remember Plants can slough off older leaves and will transfer nutrients that are mobile, such as nitrogen, when it is deficient and translocate it to new growth. Also when leaves are heavily shaded they become useless to the plant and are sloughed off. If the yellow leaves were deep in the canopy this could also explain the spotting which could be signs of fungus caused by poor circulation.
 

afman916

Member
Thank you - I thought about whether or not the leaves were shaded/low enough to chalk it up to natural processes, but I had been doing a good job of training and targeted defoliation such that I had great light penetration. So I unfortunately don’t think it can be attributed to that.

At this point, here are my thoughts -

Vegged a bit too long and the incredibly vigorous HxP is running out of nutrients. When I transplanted from 3G to 7G, there wasn’t nearly the room I was planning on for fresh soil due to just how dense the roots had grown in the 3G.

Need to alternate with plain water feedings more often - will do so moving forward. Also need to monitor runoff during those waterings.

May need to adjust pH of plain water in between feedings. Nutrient mix brought pH down to 6.5, which I think is acceptable for a soil grow - but the plain Deer Park registers 7.4; do I need to buffer that down prior to watering?
 
Depending on the EC/ppm of your plain water it’s typically not necessary to ph adjust it because there’s not enough buffer in it to really affect the soil, the soil is buffered. But if you have a ph imbalance already with your nutrient solution then it’s a good idea to ph your plain water between feedings also. I would usually ph adjust my plain water every other or every 2nd watering depending on plant health.
 

afman916

Member
Great, thank you! What’s a decent target, 6.5 or so? From yesterday, my nutrient mix solution went in at 6.5 and came out at 7.1.

Should I interpret that as a slightly acidic soil, perhaps needing to buffer even more so, with plain water at 6 or so?

Obviously still learning the ropes here, so thanks to everyone for the help and input!
 

afman916

Member
So yesterday morning was water day; plain Deer Park pH'd down to 7.0, three liters each plant. Short version is I think my previous feeding with the extra fish emulsion and cal nitrate helped the HxP - thanks all! While I still had to remove some yellow leaves, there seemed to be fewer than before and she overall just looked a little greener and healthier.

However, when I measured the runoff, EC was craaaazy high - 4.2! I triple checked and the input EC was 0.4. So I'm not sure what that could indicate? What's funny is I thought everything was going great during my visual inspection, and then I measure the runoff and it's crazy high. So my plan is to continue to give plain water Wed morning and collect/test runoff from every plant.

Welcome any ideas as to what might be causing that high EC. At any rate, I'll be monitoring and adjusting my nutrient schedule accordingly. Like I said, funny thing is I feel like the HxP definitely looks better after that heavy feeding...
 

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afman916

Member
Just wanted to give an update and also for anyone that stumbles across this thread in the future having similar issues - I know a lot of my research involves coming across threads that bear similarities to your own problems, but then things die out before the end, leaving you with more questions than answers! So hopefully I can see this through to the end and help out future growers.

The long story short is I've been alternating waterings every three days between nute mix and plain. Just this past plain I added 1T of unsulphured molasses to each gallon, as I was reading up on the benefits for microbial life and (possibly) flower size/density. I'll continue adding that during the plain waterings unless I see evidence it's causing harm.

I've been measuring EVERYTHING. Religiously. Runoff is now down to essentially input levels, both with EC and pH. I've been adding 3-4 granules of Cal Nitrate to two of the liter waterings for the HxP and it seems to help stave off leaf loss in between. I'm still having a little yellowing and lose maybe 3-4 leaves every few days, but it's from the lower regions and hasn't really progressed upward much. It seems a manageable rate, and I'll continue to supplement with minor Cal Nitrate feedings for that girl only.

I did have a minor outbreak of fungus gnats I'm controlling with yellow sticky traps for now. I have BT on hand but am avoiding using it unless necessary - not sure if it kills beneficial life too? I believe the gnats started with the Violeta girl, who is much smaller than the rest. After a few of the comments on here lead me to believe I was underwatering, I increased to three liters per watering per plant, and I think that was more than she needed and she remained a little too wet between waterings. I've since backed off for her in particular and everyone else a little bit too. I believe with my temps and RH hovering right around 75-77 and 40-50% respectively, I'm not drying out too bad even with only 2-2.5 liters per watering.

Otherwise, things are looking GREAT. I'm really trying to just get a sense for reading the plants, and not running to the internet for every little issue. While that certainly helps in most situations, I feel like in some it causes too much overanalysis and fixing nonexistent issues that only exacerbate actual issues and potentially cause more. I'm trying to not "overlove" them.

A few random smattering of pics to show progress - the colors on the Violeta are OUT.OF.THIS.WORLD.
 

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