Rust Spots - Mid-Flower

I am in Coco

Oh and yes, I did flush 2 weeks ago for the first time. Ran about 10 gallons of pH’d water through the soil, and then fed it immediately thereafter.

Just remember that any damaged leaves will not recover: look to new growth for signs of improvement.

Based on your output TDS I’d say the plants are hungry. Your soil is depleted which means you have to supplement. Unfortunately your soil is going to retain more water than coco so not sure how you continue without issues. Once you mixed in soil it’s no longer coco but soil.

I would suggest supplementing at every other watering while monitoring runoff TDS and PH. Input should be somewhere around 1,000 to 1,100 ppm 500 scale and PH to between 6.0 and 6.5 due to the presence of coco. When runoff exceeds about 1,800 ppm or so, water only until TDS drops to around 1,100 again. Watch new growth for any issues.


Hey thanks! I’m not in coco, by the way…I’m in Fox Farm Ocean Forest cut with Coco. But I’ll up the feeds if you think that might be my problem.

OK that makes sense. The only thing in coco is what ever you put there.

Thanks all for pipping in. Guess I need to up my feeds as mine run off has always been slightly lower than in.

@JaneQP I have a Gary right now. Don’t want to tell you what I named her :frowning:

Very true, soil can be tricky. I grew in Happy Frog and ocean Forest, and the numbers could be quite spectacular. Why I say look at what the plant is telling you


IMHO I think you have both calcium and Phosphorus deficiency… Cal Mag (I use General Organics 1-0-0 and for phosphorus, I use phosphorus bat guano… go lightly… but it is hard to overfeed Cal/Mag.

but the pH test is a tell all. Do a soil slurry test. You can google how to do it

I agree with @Caligurl a soil slurry test is needed.

But my assumption is that you have a salt build up causing lock out, it’s common when you don’t water to 20% run off every time and thus salts build up. This is why your seeing more tds coming out then going in, you have excess salt in your root zone.

Flush them with ph’d water (unless your waste is under 100tds) and then give them a full feed as per feed chart. That will be a sure fire way to start off fresh and give them what they want.

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@Caliguri @Nicky - thanks for suggestions. I just did a slurry test and pH was 6.2 (slightly lower than my last feed). The PPMs were really low - 175 (last feed was 760). Does that tell you anything?

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Yes it does, thanks for that info.
Your PH is within range in the soil, water and nutrients should be given at flower from 6.5-6.8

You need to feed your plant a full feeding
Feed at like 1200-14000 ppm and add cal mag

Ensure you get 20% run off ans your nutrient feed is ph’d


Thanks, Nicky!

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Can i get some help with my plants, i beleive it to be cal def, but many say leaf sporias, unsure how to proceed, will give info if you have time.

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Your plants are hungry, nitrogen from the yellow calcium from the rust
Give a full feed

Thank you for the direct answer, so many people guessing i didnt know what to do.

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