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What is going on with my Jack Herer

Hey all,
this is my first grow. I’ve got a jack herer and a blue dream growing in a coco perlite mix. I’m using Sensi coco A/B, CalMag and B-52. My water is about 5.8-6ph. I don’t know my ppms but I am just following the instructions on the bottle. My temps range from 22-28c and my humidity sits around 50-65 RH. I just don’t understand what’s going on


Looks like a heat issue and the leaves are cupping


But your temps are fine hm. Here for the responses. Best of luck brother

Yeh I’ve had the same response on other forums saying it’s heat but it really doesn’t get that hot in my tent. Could it just be the pheno? Or a stage?

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I’ve never seen this before but I bet I know who to ask for ya :wink: @Jess @dbrn32 @Growernick @tdubwilly any idea what’s going on here peeps?

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I’m of em will kno

Btw welcome @nate_g42

Thanks hoppie hope I can get some help. It has me stumped

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Is there a fan blowing directly on it?


How much nutrients are you using and how often? A couple of my girls looked like this and it turned out to be a ph issue which caused nutrient lockout and burn… I ended up having to do a big flush to them and after about a week they recovered…


I may be wrong but sensi AB+ a cal mag might be too much for them… from what I’ve read and heard most AN base nutes have enough cal and mag in them already


How far are your lights from the canopy? Your temp in your tent and your temp at canopy level may not b the same. This is a temp issue. The fact that one plant is doing it and not the other just says one is more sensitive than the other.

What type of lights are u using?


Thanks for the reply davesnothere. I’ve been doing 4ml of A/B, 2ml CalMag and 2ml of B-52 per 1ltr.

Ok that’s interesting. So do you think I’ll try a week of just A/B and leave out CalMag?
Thanks again for the reply

Yes there is a fan in there but not blowing directly on them it rotates above the light and just gives them a slight move


My temps at canopy level where I hang my thermometer is 25 celcius. It’s so odd to me. My light is about 60cm and it’s a viparspectra r900

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Those curling leaves are a sign that the plant is in heat stress. That particular plant doesn’t like that 28c. 82f isn’t that high but for some plants at 24” might not b good if there isn’t sufficient wind.

She just might b a finicky bitch. They exist in our plants too. With your ph being in line just keep taking care of her. You haven’t foliar fed have u?


I know coco is a whole different ball game but if I were to feed that high ppm amount to my plants in soil that early they wouldn’t be very happy… AN has great customer service and I would definitely recommend calling or emailing them to ask if that particular base nute needs extra calmag… the second picture looks exactly like my plants that I burned a while back, if the tips start changing I would flush fast.

This is what they looked like before I decided to do a heavy flush.


I can tell you that you shouldn’t be doing this, no matter the nutrient mfg

I see nutrient burn combined with deficiencies on your worst plant. On top of that your plants are still young and don’t need to be inundated with fertilizer, especially to the mfg’s recommendations.

Cut you nutrient schedule in half. I believe you have feed them too much, burned them, and the fertilizer excess has started to cause lock out on certain nutrients.

Too much phossphorous will lock out magnesium and calcium while too much potasium will lock out iron and zinc and your plant looks deficient in both.

The plant that is really bad will probably need a flush to wash out all the excess fertilizer

P.s. are you sure your pH meter is correctly calibrated?



@davesnothere is sniffing down the culprits tracks!!


I’ll shoot them an email and see what they say. I’ll give them a big flush out and reduce the nutes by half. Should I also be feeding everyday and wait till the coco surface dries out before feeding?

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