Why do the leaves have yellow and green stripes?

[Dagmar]

I've been growing for a while now but this is my first coco coir grow. Plant: Somango XXL, Light: 450 LED, Coco is mixed with 30% perlite, I alternate watering and feeding about every 3 days (as needed), PH'd to about 6.0 (run off is about the same), Fox Farm Nutrient Trio (hydroponic version). Temps range from 65-75 degrees, humidity 40-50%. Just flipped to 12/12 lights a few days ago. The stripes started 2-3 weeks ago.

I have 2 Somango XXL but only one has yellow and green striped leaves. Is this due to a different phenotype or to a deficiency? I don't think it could be a deficiency since the other Somango does not have this characteristic, nor does the Mystic Blue growing next to them. But it looks like a deficiency? What's going on? Any thoughts or ideas?

[DoctorJohnson]

That's a fairly serious magnesium deficiency, which is common in coco grows that don't supplement Cal/Mag. http://www.growweedeasy.com/magnesiu...iency-cannabis

You should start adding Ca/Mg supplement immediately, and lots of it (e.g. 5 ml/gallon GH CaliMagic).

Add Ca/Mg to your nute mix before anything from the other bottles to prevent it falling out of solution (at least with the GH brand. I assume that others are similar.)

By the way, unlike soil, you should water coco every day. You can't overwater coco, especially with 1/3 perlite. (Coco growing is essentially hydroponics in a non-nutrient fiber matrix, and very different from growing in soil.)

I dilute my nutes so I can water my coco grow with nute mix every day (twice a day, actually, on a timer) to give the plant a steady diet (just like with hydroponics) rather than a feast/famine cycle. It works well and I recommend it. Start with about 1/2 strength of Nebula's recommended dosing schedule if you want to give that a try.

[Dagmar]

Hey, Doc! I neglected to mention that I DO use CalMag. But I hadn't read anything about what you said about adding "Ca/Mg to your nute mix before anything from the other bottles to prevent it falling out of solution". I don't understand - can you tell me more? I read recommendations on coco that included watering every day to only watering once a week. Do you just water with nute mix every day or do you alternate with water? I add CalMag to every watering. Thanks

[9fingerleafs]

It could totally be a phenotype difference. One is happy with the nutrient levels one is not, like doc said a little calmag should do the trick

[D.A.A.S.69]

Hello Dagmar, I don't know if it's imperative that you always add cal-mag first, but I have always heard that, and that's what I do too, but I would also like to know if you Have to use it first, because I know a few times ,I forgot the cal-mag first, and added it last, and I didn't get any lock-out, that I can remember.

[9fingerleafs]

One of the main problem with the calmag is that it sometimes reacts with the ph down or other acidic nutrients to form a non soluble molecule of calcium witch sinks down at the bottom and never reaches the plant. Creating a white sediment where you mix the nutrients

[D.A.A.S.69]

Thanks@9fingers, with the way my water,and nutrients are, I never have to use ph up-down, every now an then I use some, but not often. Maybe that's why I didn't lock-out my plants. Thanks.