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[romeishome]

Hello guys and gals! I am having some issues with a couple of my plants… They are Gorilla Zkittles from Barney’s Farm and I’m growing in soil (Biobizz light mix and perlite – 60/40) under a Mars Hydro SP3000 (old model – 2022) at 75% power and about 40cm away from the canopy. I planted the seeds the last week of May. After vegging for 4 weeks in 5 liter pots, I recently transplanted them (two weeks ago) into their final home (20 liter Airpots) and mixed Growdots into the mixture at the medium feed rate. I use my Pulse monitor and a temperature/humidity controller (Inkbird) to keep the VPD stable around 1.2 (usually around 26-28C @ 60-70% RH). At this point they are 6 weeks into veg and I was really happy with the results I was seeing. I was alternating watering with Recharge and plain water (bottled at PH of 7.0 – I used to chase the PH but I stopped some time ago because I am growing in soil and I read that soil buffers the PH) and I was preparing to flip to flower when the 4 weeks of nitrogen runs out. I started to notice the yellowing on the outer edges of the leaves and assumed the Growdots hadn’t fully kicked in and/or the Recharge would help balance things out. I put the scrog net on yesterday (only my second time using a scrog net) and checked on this morning to find their top leaves clawwing down and looking generally miserable. I also see some purple on some of the upper leaf stems. Any ideas what is going on here? Is it a deficiency or toxicity? Am I over/under watering? Were my lights too close? (I raised them a bit to give the plants a break until I figure out what’s going on with them) Is this a PH issue? Maybe the bottled water at 7.0 PH is too high? Any and all comments are welcome! I haven’t done anything to them yet today except raise the lights a bit… I was going to add about 1-1.5 liters of plain water to them but decided to wait until I hear from the DGC!

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Discussion

[jonnydanko]

Maybe check the soil for bugs? I had root aphids (I think), and the plants looked similar.

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[jmystro]

Roots pests attack and stress roots as quickly as anything. When you’re doing everything right but the plants are still dying has to be frustrating af. That’s always a possibility but when I read 40% perlite with Grow Dots I knew what was most likely the issue.

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[vtgrows]

Looks like overwatering to me.

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[jmystro]

Over and under watering can droop leaves the same way so that’s why it’s important to have as much info as possible. Knowing his soil has 40% perlite, we can reasonably assume they are not being over watered.

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[goodguycanna]

I’d hold off on any changes. Might be a simple reaction to the moment putting the skrog net on.

If that’s the case, you would see recovery over the next few hours.

Are you watering based on a schedule or moisture content in the medium?

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[romeishome]

I am fighting against the urge to “do something” and am just observing them at the moment… I water them by pick up weight.

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[jmystro]

Your pH and mineral buffer is out of range for sure as 40% perlite is way too much to use in a mix with Grow Dots. Your not growing in soil at this point when your mix is half inert. Perlite has no ability to hold nutrition so your growing media can’t hold on to much of the slow release nutrition Grow Dots are providing. When you water, you’re just washing out minerals as they have little soil to stick to. Your mix is more for cyclical top feed or flood and drain hydroponic systems. They look under watered as the media is probably drying out too fast with that much drainage. There is no fix when you start wrong. Sorry.

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[romeishome]

Thanks for the info! I would say the perlite is a little less than 40 but still good info to take into account when I mix up soil for my next run. I used to use regular plastic pots then switched to fabric pots to help with aeration with that same 60/40 mix. Recently I switched over to airpots and kept the same mix. So what can I do if the Growdots aren’t feeding the plant correctly because I screwed up the soil mixture ratio… should I just top water and feed them with my normal liquid nutrients and ignore the Growdots in the soil and hope I don’t run into too many problems in flower?

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[jmystro]

If I were you, I would find a way to water more often with little runoff. You can’t over-saturate a media with that much perlite. Grow Dots has all the nutrition the plant needs. We just don’t want to wash it out. Ion exchange occurs in water. The organic matter/soil can hold and ‘buffer’ nutrients for later use. Your plant will be fine without spending more money on nutrients. Just can’t let the media get even a little bit dry.

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[moistcube]

Like 🔥

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[phyto2theendo]

I had odd curling like that on my fannies when my PH was off in coco

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[romeishome]

I’m going to pay closer attention to my ph levels, but I think jmaystro nailed the problem…

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[romeishome]

Thanks guys for all the replies… but what about these pics? I have red/purple leaf stems and yellowing on the outer edge of newer growth leaves…

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[romeishome]

Is this a cal mag issue?

Or is it another deficiency linked to my mistake in mixing up my soil like jmystro said in his reply?

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[jmystro]

When just the leaf blade edge yellows (before turning brown when untreated) is from a lack of potassium. Plants are very potash hungry throughout it’s entire life cycle. When plant roots get hurt, nitrogen and potash are the first signs of an issue as they are needed in the highest amounts. Calcium deficiency shows up as tiny brown looking burn spots. Magnesium deficiency shows as interveinal chlorosis (fancy way of saying yellowing between leaf veins as it looks like tiger strips). Mag has yellowing along entire blade while potash just yellows edge.

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