Help with plants 39 days into flowering, Burn or deficient? (Pics inside!)

So, these plants are currently on day 39 of flowering and haven't looked great for about two weeks now, progressively getting worse. Some plants appear to be nutrient deficient, while others burnt. I cannot pinpoint the cause or causes. Some of the leaves that are yellow and brown are due to wind burn. These are grown in a 4x4 tent.

I have 5 plants total, all in 7 gallon (#10) pots. I've been using Subcool's Super Soil method. I made no adjustments to his recipe, or method of application. After mixing the batch, it was composted in a garbage can for over 8 weeks. I went conservative on the amount of super soil I used in each pot, maybe 20% on the bottom with Roots Organic on top. All plants were top dressed with super soil on day 28. No other nutrients or fertilizers were used throughout the plants life cycle, only water!

If you notice the first 3 pictures the leaves are canoeing/tacoing upwards. This started on only one plant, and now the others are doing it as well. Below are some facts about my grow:

Strain- Afghan Skunk by Advanced Seeds (next grow I will be using TGA). Hybrid, Indica dominant. Breeder's website says flowers mature in 50-65 days.

Water- I've been using tap water that's been aerated with an air stone for 48 hours before watering. PPM is around 60. I add GO Cal/Mg+ raising the total ppm to around 130. pH going in is 6.5. Soil pH is around 6.2.

Temp/Humidity- 73 degrees with lights on, 66 lights off. Humidity 40% lights on, 50% lights off

Misc- HPS light being used is no less than 8" from the canopy so I don't think this is heat stress, although I could be mistaken?

Everything was going great but now that I'm in the home stretch, these girls don't look happy. I might only have 15 days until harvest, I hope they last that long. Does anybody have any input as to what is causing these issues? Perhaps it's too late for them to recover? Any and all comments are greatly appreciated. Thanks in advance! def

Your PPMs are way to low for flowering.But it looks like it may be heat related to me,your ambient temps are perfect but unless I missed what wattage your HPS is,if it is a high wattage 8" could be too close.

Interesting. What do you recommend the PPM be during flowering? I'm using a 600w HPS in a 4x4 tent. Thanks for the reply!

The PPMs are going to be strain dependant on what they like but I think a safe range 1200-1400 at least more if they can handle it. As far as the 600w maybe this can help your at the threshold of too close with that distance.
View attachment 2669183 Good Luck. NVM I just reread your original post about the PPMs and misunderstood,I thought you had 60 PPM after adding nutrients.Still think conoeing is heat related though.

sohighifly said:

The PPMs are going to be strain dependant on what they like but I think a safe range 1200-1400 at least more if they can handle it. As far as the 600w maybe this can help your at the threshold of too close with that distance.
View attachment 2669183 Good Luck. NVM I just reread your original post about the PPMs and misunderstood,I thought you had 60 PPM after adding nutrients.Still think conoeing is heat related though.

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Sohighfly, he said he was using super soil. That soil is already super hot.

Duster, dont add 1200-1400 or youll really burn them plants. Yes you might need more nutes but not that high.

As far as distance goes, if it doesnt burn you, it wont burn them.

Thanks for the chart, I'll back off on the distance of the light to see if that helps. Yeah, it's 60 PPM out of the faucet. After adding the Cal/Mg supplement, I raise to around 130, thinking more than 300 or so is considered "hard" water. Or does this rule only apply to water before any added nutrients are mixed in? So to be clear, you recommend a total PPM of 1200-1400? That would be 1140-1340 of Cal/Mg added to my 60 PPM of tap?

Is your thermometer low to the floor or at canopy level?

The thermometer is closer to the floor. I have it resting on the brim of a pot. I'll move it up and see what it reads. Thanks!

Don't add anything as mentioned above...you are using super soil...ur nutrients are already in the soil. I personally think you should back off the calmg for a couple feedings. calcium and magnesium kinda work together and an excess of either can block out the other ie. excess Mg will block Ca and excess Ca will block out Mg. some of the deficiency symptoms look like Mg and Ca combined while also looking a little burnt. I would feed them with just plain water for a couple of feedings and see if it improves.

duster74 said:

The thermometer is closer to the floor. I have it resting on the brim of a pot. I'll move it up and see what it reads. Thanks!

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Cool beans. I hope you find your problem. Get those babies pumpin swollen buds and fat trichs!

Subcool does say to use some added Cal/Mg into the supersoil if using RO. I'm not using RO, but my water out of the tap is 60 PPM, which is close to pure. Since it wasn't added into the super soil when I mixed the batch, I've been supplementing with 70 PPM of liquid Cal/Mg during each watering. Is this too much, or too little? Thanks again.

mehrific said:

Sohighfly, he said he was using super soil. That soil is already super hot.

Duster, dont add 1200-1400 or youll really burn them plants. Yes you might need more nutes but not that high.

As far as distance goes, if it doesnt burn you, it wont burn them.

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Yes,I already edited my post after I went back and reread thanks mehrific.

Thanks bobswizzle. I will not add the Cal/Mg and see what happens.

Looks like phos, mag and zinc def.. a couple guano teas will fix. Get on your compost teas too.

If super soil is too hot. There's nothing you can do. You did not let it cook long enough. If you don't let it cook long enough early deficiencies will occur.

I stopped doing super soil myself. Its over rated. Living organic soil is much much better. I use shrimp / crab meal instead of bone meal, blood meal and guano. Plants seem to love it way more.

Looking at it I would say you seem to have high levels of N (dark green, also green veins) combined with a magnesium deficiency. (yellowing from bottom up with leafs dying starting at the tips)

hyroot said:

Looks like phos, mag and zinc def.. a couple guano teas will fix. Get on your compost teas too.

If super soil is too hot. There's nothing you can do. You did not let it cook long enough. If you don't let it cook long enough early deficiencies will occur.

I stopped doing super soil myself. Its over rated. Living organic soil is much much better. I use shrimp / crab meal instead of bone meal, blood meal and guano. Plants seem to love it way more.

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I have read The Rev's book, "True Living Organics." It seems very interesting and might be worth a shot trying sometime. I've also been following Cann's posts here in Rollitup.

automated said:

Looking at it I would say you seem to have high levels of N (dark green, also green veins) combined with a magnesium deficiency. (yellowing from bottom up with leafs dying starting at the tips)

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The Super Soil does seem to contain high levels of N, and not much K. But, it's supposed to be a tried and true method. I believe I mixed my batch exactly to his 2010 recipe. Who know, it's possible some of the ratios are off by miscalculation.

duster74 said:

I have read The Rev's book, "True Living Organics." It seems very interesting and might be worth a shot trying sometime. I've also been following Cann's posts here in Rollitup.

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I don't do rev's recipe. Mine is closer to cootz recipe.

Check this thread https://www.rollitup.org/organics/636057-recycled-organic-living-soil-rols.html


Also sub doesn't add k because the kelp in the roots soil and when the coco breaks down it creates k. Personally I think it lack k. Add some kelp meal and green sand for k.

I know you have received a lot of responses to this already but just wanted to mention I just heard on the "Ask Danny" section of Free Weed with Danny Danko episode 3 that the "dreaded taco shell" symptom usually contributed to a calcium and magnesium deficiency at the same time.