HELP! What's going on here?

[Franklin]

I have an issue that I'd love your thoughts on. All organic living soil grow, 15 gallon fabric pots, 3x3 viparspectra 130 watts at the wall (veg lights only) plus green sunshine 200 watts that was at a six but is now dimmed down to 3 or 4 a week ago when the symptoms started. Both lights were about 30 in away but I moved them to 36 inches away a week ago when the symptoms started. Plants are about 5 weeks. Been getting taco curling consistent with heat/light stress and inter veinal yellowing that looks like magnesium deficiency except the affected leaves are up top. I have a rotating fan that was blowing directly on them but lightly (ac infinity set to 3, I've turned it down to 1 in case it was wind burn).

My environmental conditions have been pretty spot-on although I may have overwatered them a little bit. I generally water with plain water, I do not pH my water but it comes out of the tap neutral. I have added a couple rounds of the root wise bacterial blend and a couple of aerated compost teas with sprouted seed tea. I tried to keep these pretty gentle but I did notice that the plants didn't not seem to love that so I have not been doing it regularly. And they've been a touch too cold. They are at about 71 to 72° during the daytime, VPD ranges from .9 to 1.0. at night time it gets pretty cold in there because the exhaust fan cranks on to raise the VPD because that shoots down when the temperature drops so it becomes a bit of a cycle, it's probably 65° at night. I recently have turned a space heater on outside the tent but since this is in my basement that's going to get pretty expensive.

Anyway I think that's about all that's important. Despite all my adjustments that I just described above, I'm still getting this issue and it seems to be getting worse.

AGH UndergroundFarmer I would love your input because you both use organics/ living soil. @mrfurley You always seem to know what's going on.

[Blowdout2269]

I definitely see some heat/light, and possibly some wind stress. The yellowing could be part of that. It could also be symptoms of a potassium deficiency.
That's about all I got for ya. Let's see what others think.

[Bowhunterwoody]

I'm subscribed. Having similar issues at about week 8. Not on the top or the bottom leaves. Middle fans.

[Bowhunterwoody]

Sorry Franklin, didn't mean to hijack your thread.

[Franklin]

No worries, hopefully can find help for you too, though the issues look different to my eyes

[Bowhunterwoody]

Yea I don't have any canoeing, but the yellowing at the edges is what I thought was similar.

[crucialbunny]

The cabbaging leaves makes me lean toward excess nitrogen.

[Franklin]

That's very helpful, thanks, didn't know cabbaging was caused by that.

[homegrown]

I personally think its light burn or light stress. Canoeing, yellow leaf edges, mostly top of the plant(the old big fan leaves seem to be ok) Im dealing with such an issue at the moment but im in the final stages of grow so not really concerned. I would turn your lights down a bit more and see if it settles down.

[Mr.furley]

I'll agree with crucialbunny on that toxicity, from the pics the leaves look on the dark green side and starting to get yellowish tips. Excess is almost always amplified on the top of the plant with light burn to follow so smart move raising the lights.

When we start to micromanage our environment we start creating faster problems for ourselves, with cold basements it can be expensive to keep the temperature spot on but its what it takes to stay trouble free. If you're having swings in temperature and humidity it can also exacerbate simple problems with the plants when we make mistakes. Point being if you keep perfect environmental conditions you can always rule that out.

[AGH]

So I initially thought nitrogen toxicity as well since the leaves look dark and someone described as 'cabbage-y' which is a perfectly accurate way to describe them! But generally with Nitrogen toxicity the leaves (or at least the tips) turn downward, not upward.

What else has darkened leaves with yellowed tips/edges I wondered. Copper deficiencies seem to show themselves like that: https://www.growweedeasy.com/cannabi...per-deficiency
- Leaves get dark with blue/purple undertones
- Symptoms are worst closest to the lights
- Tips and edges turn bright yellow
- Leaves feel tough or dry

In organic grows, copper deficiencies aren't usually due to a lack of copper in the soil, rather some sort of root issue. Often pH can be the cause, but as long as you have a healthy soil biome and not an extreme pH in your water, that can be ruled out. Overwatering can cause it as well but it appears that's not the case but you could double check that too.

WAs others have mentioned, it seems most likely hat it's light stress. You've got some powerful LEDs and that can easily cause the symptoms...yellowed leaves, mostly at the top, canoeing. Of course, it seems like you've taken action for the light stress by reducing the intensity and/or raising the fixtures.

You might take a multi-pronged approach and in addition to adjusting the lights, make sure your watering regime is under control (it's so super easy to overwater soil, especially living soil since it soaks it up so well!). To fix the copper deficiency, not too much to do other than make sure your environment (especially lights and watering/root health) is dialed in. If it's Nitrogen toxicity, that should resolve itself since it sounds like you've stopped adding teas. With organic grows, nitrogen toxicity isn't as common but cannabis LOVES nitrogen and can be greedy for it even with the mycorrhizal fungi buffering/balancing out the nutrients that it gets...afterall, if Nitrogen is in the soil, the plant is going to ask for it. So basically by adjusting the lights, making sure the watering regime is correct, and giving it some time, you cover all possibilities: light burn, copper deficiency, and nitrogen toxicity.

It's great how 'letting go' can often fix life's troubles!

Keep us posted on how things progress!

[changeofpace2014]

What strain are you growing?

Regarding the inside temps during off cycle. I use a P.I.D to control a small space heater set on low to cycle it on and off, it cuts the on time by at least 1/2, however some here use plug in devices from amazon to control heat and or humidity in the tent...The later is probably the easier way to go but the p.i.d I use works great for that. I would be very surprised if it is light burn with 36" between the plants.

Have you checked ph at the roots maybe a intake adjustment is required.

[Going2fast]

Just had a similar issue with a couple of plants but mine were in flower. Light burn was the main culprit along with k defiency. With one sp3000 I could get away with 12" away with some strains. I added a second and now I have them at 30-36 away. Started seeing a lot of tacoing after adding the second light. Something Mr furley mentioned when helping me out. He asked if I use well water and does it have iron in it. Yes to both and I'm going to do an experiment with my breeding run after this one to see if too much iron could be a factor.

[changeofpace2014]

Green Sand filter will take all the iron out the well water but it will require..perhaps you already know ..https://www.cleanwaterstore.com/reso...nsand-filters/