Is this a burn or a deficiency worth addressing?

[terp182]

Hi! I'm having an issue with my plant below. Any tips or insight on how to help her is appreciated! I've got two others in the same medium and nutes doing much better. Any ideas what could be affecting this girl?

Problem: Low growth, yellow/light green color on the interior of leaves

Medium/grow method: Mostly coco with Roots Organic and Perlite mixed in

Feed: and supplements used: Megacrop 2g/gallon, Cal Mag 3mg/gal

water source: Municipal (22 ppm baseline)

PH in the root zone: Feed/Nutes is ~5.9

Strain/age: Mephisto Zamaldelica Express, 12 days from sprout

light used: Mars SP-3000 @ ~18", 40%

Climate: 73-78 F, 60-75% RH

 

[elcoloan]

While others chime in.... i wonder if this could be an issue from mixing Roots Organic into coco and treating the medium as just coco? Curious that the others are fine as you say... maybe just a delicate phenotype?

 

[terp182]

I was wondering the same thing. The thought process in the moment (the original plan was all coco/perlite but I found some soil) was that it would buffer the ph a bit and maybe be a good environment for the microbes. The double grape (pictured) is loving the same treatment.
One thing I didn’t mention is that i haven’t watered to runoff with this - only on the first soak before seeds went in. I’ve kept the ppm low to account for this and only watered in increasing diameter rings around the seedling to try to encourage downward growth in the autopots.

 

[St. Tom]

hi bro i would start be feeding to run off low ec feed as not feeding to run off your going to get build up but not normally this early anyhow that's what i would do and maybe check your runoff

 

[Proph]

There are a bunch of variables at play.. What is the ratio of coco to soil? What kind of coco was it, bagged or brick? You're feeling pretty heavy for 12 days.. and you're giving the medium more calmag than you are nutrients.. I have yet to see a grow go well that is done in a mix of soil and coco. They are two completely different mediums that are treated differently. I have known a couple of people that added a few handfuls of coco to soil pots for added water retention, but that about as far as it goes.

Every plant from seed is different. You have one plant that seems to be able to handle the heavy feedings for now, and one that is sensitive to the way it's being fed. The one that is handling it ok looks very dark green and could see issues soon as well. Reading the plants is your best bet. If you have a ppm meter, I would start checking the ppms of your feeds before you use them, as well as the ppms of the run off when feeding. But a lot depends on how the coco and soil was mixed, and how much of each was used.

 

[terp182]

Thanks so much for that insight. It's Botanicare coco/perlite, bagged. It's definitely a coco-heavy mix. The PPM of the feed is around 540. Should I flush the ZE and then look for PPM within ~200 of the 540? Or lower for this stage of growth?

I'm perfectly fine backing off the nutes; I'm drafting off a couple others' grows here in similar setups/schedules and this is literally my first attempt ever, so the learning curve is steep and I'm leaning hard on their grows as a baseline. I'm still learning just about everything at this point! Really appreciate the tips.

 

[Proph]

Thanks so much for that insight. It's Botanicare coco/perlite, bagged. It's definitely a coco-heavy mix. The PPM of the feed is around 540. Should I flush the ZE and then look for PPM within ~200 of the 540? Or lower for this stage of growth?

I'm perfectly fine backing off the nutes; I'm drafting off a couple others' grows here in similar setups/schedules and this is literally my first attempt ever, so the learning curve is steep and I'm leaning hard on their grows as a baseline. I'm still learning just about everything at this point! Really appreciate the tips.

If it's mostly coco, I would treat it like coco as much as possible. I grow organic now, but when I was using nutes and growing in coco, the highest ppm I would use would be 550 max.., and that was in late flower.. I also wasn't feeding (using nutes) with every watering. It's much easier to add more or something if needed, than it is to remove excess if too much of something is added. I would definitely check the ppms of the rum off and try be in the 200 range.. You don't necessarily have to "flush" the medium. You can just use plain water for a few days then recheck the ppms. But either way, 540 is super high for week 2. These are the ppm ranges I use for autos

W1- 100 ppms
2- 200
3- 400
4- 450
5- 500
6- 525
7- 525
8- 525
9- 550
10-550
11-400
12-0

This varies and all depends on what the plant is showing/saying. These are just general ranges to help you avoid nute burn and lock outs.

 

[terp182]

Thanks so much for this info! It's only been fed a few times but I'm happy to dilute and see how she reacts. This is great data for a baseline to work from. Thanks again.

 

[Mañ'O'Green]

No one has talked about PH yet and we should. First off that is the best municipal water I have seen at 22 PPM. I would double check the meter and the water. Get a copy of the water quality report from your city, It is usually online. The sections of interest are the Water Hardness and Sanitation.

If it is true at 22 PPM you need to add 75 PPM of Cal-Mag on a regular basis. What is the PH in the root zone and of your starting fertigation.

 

[terp182]

The nute water going in is around 5.8-5.9. I checked the PPM with my own meter - I'm in WA state. Is the root zone ph detectable by runoff or does that require a non-liquid pH thing?