Deficiencies

[paintslinger78]

Autoflower in coco coir and GH nutes. Been struggling with this plant. I’ve bumped the nutrients around but nothing has helped. The other plant has no issues.

[DabberDog]

What is your pH and are you using calmag?

[paintslinger78]

PH is 5.8 to 6.0. Using GH calmag at one teaspoon per gallon.

[Allotrope1000]

Well, paint...,
Is the other plant from the same seed batch?
My experience is that seeds from the same batch can inherit different genetics, resulting in different phenotypes and growing characteristics. Just a thought.

[paintslinger78]

Yeah it’s from the same batch.i was thinking it could be genetics.

[Ckbrew]

I'd stay closer to pH 5.8 at that stage. What kind of coco did you use and did you saturate it with calmag when you started the pots? When I build the pots I saturate the coco with water using 30ml/gallon calmag and pH to correct. This is ONLY for the first dose to get the coco wet using mother earth coco/p 70/30. Your dose is good but if you didn't buffer it you will be playing catch up. Coco binds calmag so it is not available to the plants unless the saturation sites are filled up. It could just be genetics. I have had one plant looking yellow and lagging in a batch of others that were all getting the same feedings, and environment. Never did get it to turn around.

[paintslinger78]

I’m using Fox Farms cultivation nation 70/30. I didn’t buffer the coco. I’ve been using it without buffering it for over a year with no issues. I’ll try buffering it next time around. I’ll just ride these plants out and see how it goes.

[Ckbrew]

A good experiment would be to up the calmag on only one plant and see if there is a difference. Sometimes producers change up their product. It would be less expensive for them to not pre-buffer the product.

[Bluey]

At low pH in coco your plant cannot absorb magnesium, and what we are seeing here appears to be the start of a mag deficiency.

To avoid this, especially in veg in coco, you need to let the pH go higher. Below 6.0 you won't get enough to be absorbed at the roots so let your pH run from 5.8/9 to allow uptake of manganese, boron & phosphate to a high of 6.2/6.25. Above 6.2 is the sweet spot in coco for Mag uptake.

Keep adding the CalMag at the same rate but once you get the pH right you typically can drop it back to every 2nd feed.

[paintslinger78]

I might try bumping the cal mag up for that plant. I’ll adjust the PH to the high side of 6.2 and see what happens.

[Bluey]

If you follow what I said it will recover. If you go off on some tangent and increase the calmag and not vary the pH like I suggested, you tell me, what's going to happen?

[paintslinger78]

I’m going to adjust the ph.