Hi all.
I’ve switched to all organic grow, done a couple of runs in this soil. Last time I unloaded the soil and amended with homemade worm compost and earth dust. This time I tried to go no till and just gave it a layer of fresh worm compost and a bit of earth dust. You can see from the photos that it’s not going well. I’ve never had a problem like this before. Maybe looks like potassium deficiency? What is your diagnosis and how do I fix in an organic grow? Think about some compost leachate for quick nutrients and an additional layer of compost but hesitant because maybe I’m actually over feeding?
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Hey buddy!
Ok, let me take a stab at this…
First of all I see some really dark greens, as well as some clawing. That tells me that you got a bit of a nitrogen overload.
The yellowing between the veins is likely a magnesium deficiency. Though it could have something to do with potassium, if it’s only effecting newer growth.
As for the wrinkly leaves, this could be a number of things. Root issues, environmental conditions, pests…idk. Do you see any type of bug? How close/strong are your fans?
I’m sorry I’m not a better help for ya bud. I’m trying to find an article on GWE.
Maybe someone like @GrouchyOldMan can chime in.
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Did you happen to mix up your soil and castings the same day you planted/threw seeds?
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Have you used any oyster shell or dolomite lime to keep your PH is line as you reuse your soil? I’ve had problems in the past with soil acidification over time as I reuse soil. Without knowing more about your soil mix, your amendments and such it’s hard to say but an easy way to check is to take 1 cup of your soil and mix it with one cup of PH 7 water, leave it for an hour or so and then check the Ph of the slurry. It’s not totally accurate but it will give you a good indication of your soil PH and you can make adjustments up or down as needed.
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This is likley where I’m at with my soil.
I still haven trained myself to to amend properly.
Thanks guys. Last night I had a realization. I had my pots sitting around outside the tent for a couple months between grows. I also have an adopted cat who loves to pee in plants (I have to put barriers on my houseplants to keep her out of it). I suspect she was doing a fair amount of peeing in these pots, resulting in nitrogen and phosphorous toxicity. Gross, I know. I’m going to try to flush these. Unfortunately they’re such big pots, this won’t be easy and will probably waterlog them. Before I go at it if you have any other ideas let me know. I’ve never had problems like this before.
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The more I think about it, the more I think this is the right answer. The plant that’s doing the best is the one that about half of it was from some reused soil from a different bed that the cat would not have had access to
I just tested the ph and it’s fine, thanks for the suggestion
Do you have gnats?
Not many. No signs of a massive fungus gnat issue, in fact it’s fairly low compared to the other living soil grows I’ve done, probably one fifth of the usual issue
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I just finally got off my lazy ass and waged war with the little bastards.
It’ll be easily won, but I did procrastinate longer than I should have.
Fungus gnats can cause weird twist leaf deformities also.
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What did you use to fight them? I have begun the process of flushing, it is wet and cold down there in the basement moving 4 pots of 15 gallons of sopping wet soil from my utility sink back into the grow tent.
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Hey bud if it’s possible try to have the soil recycling in compost bins between grows. Amending can be as easy or as complicated a process as you want really. A well tended green/brown compost mix will usually provide the soil with a nice starting point of ph and microbes/nutrients. If you come across supplements add them in. Mrs Herb caught a big mud crab yesterday we cooked it up and I’ll be crushing the shell and adding that to my current amending compost mix.
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I’d take the pots out give the floor a clean as you’re in fabric pots I’d fertigate/irrigate to let the top soil dry out. Keep using the sticky traps and that usually helps with the gnats.
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Sticky traps and fans are the first line of defense.
Then comes Diatomaceous earth on all DRY soil surfaces and along baseboards and corners. DE only works when its dry. So you have to reapply after waterings…or water from the bottom.
And the end-all to their life cycle would be BTI.
I use mosquito bits. I mix some granules into my soils before hand, and I will also steep some in a jug of water and do a soil drench if needed.
It looks like you might be dealing with a potassium deficiency, based on the symptoms in the photos. With organic growing, nutrients can take longer to become available due to the natural breakdown process.
In your case, the no-till method might not be providing enough immediate nutrients for your plants, which could be causing the deficiency. You could try adding some compost leachate for a quick nutrient boost and layer on a bit more compost, but be careful not to overfeed.
Try to conduct a soil test to get a better handle on the nutrient levels. Good luck man
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Thanks for the advice everyone. I was really weighing whether this was a potassium deficiency or a nitrogen and phosphorous toxicity but after looking at lots of pictures and considering the usual behavior of my cat, I went with the toxicity. I’ve flushed it and will keep an eye on new growth for the next week. Maybe it is a deficiency and if so at that point I’ll hit it with some leachate.
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@sativasavant nailed it. In organics, under best conditions with a healthy microbial population, assume 10-14 days for nutrients to become available. This can also change based on the microbe community composition, you could maybe speed it up by inoculating with decomposer genera. When Cannabis switches to flower it becomes more sensitive to potassium concentrations according to current science literature. If you’ve supplemented with any calcium or magnesium it may not be bad to supplement K as well because all these nutrients compete with each other for uptake
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Thanks @ThePotanist . An update. I flushed and things didn’t improve. So a few days ago I mixed up some compost aerated tea and leachate and added that but it’s too early to tell if things are improving. I agree that it looks like potassium deficiency but here’s what’s weird: there is a ton of organic matter in that soil and I’ve innoculated it with a whole host of bacteria and fungi. There really “should” be plenty of nutrients I’ve ordered a soil test kit so so we shall see what’s going on.
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Hi everyone, thanks for reading, I now have a soil test in handy and I find some of it hard to believe. It says I’m very low on nitrogen, high on potassium and phosphorous, low on iron, manganese, and boron. I know nitrogen is highly mobile and some places won’t even provide a reading because of this. Looks like I’ll be adding some lime, blood meal, and micros. Any thoughts on this report from anyone?
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