Unidentified red/brown spots on leaves: It can be fungus so jump in and help

[Emilya Green]

I use apple cider vinegar to make my home made calmagphos+, and I assure you it does not kill the microlife. If I poured a lot in the soil straight, it is a pretty strong acid, so yes that would kill... but just be careful with it... a little bit of vinegar is not going to hurt anything... a lot of people use it as a pH down.

Emmie's DIY CalMagPhos+ From Eggshells

This is an awesome product to use during the changeover period from growing to flowering/fruiting on all of your plants. For most of us, by using molasses we are able to get the magnesium that our plants need, but for our calcium needs, most of us have to fall back on a commercial product, and...

www.420magazine.com

These pictures were taken with photo-flash on. I got lots of other leaves looking exactly the same. I will share some more tomorrow. Do you think that picture from that grow website is a good example of Mg deficiency?

Yes, we see magnesium deficiency all the time here at 420mag... and yours is not that. The example you showed is a good one, but it is not what your leaves are doing.

 

[TriangleCheese]

I use apple cider vinegar to make my home made calmagphos+, and I assure you it does not kill the microlife. If I poured a lot in the soil straight, it is a pretty strong acid, so yes that would kill... but just be careful with it... a little bit of vinegar is not going to hurt anything... a lot of people use it as a pH down.

Emmie's DIY CalMagPhos+ From Eggshells

This is an awesome product to use during the changeover period from growing to flowering/fruiting on all of your plants. For most of us, by using molasses we are able to get the magnesium that our plants need, but for our calcium needs, most of us have to fall back on a commercial product, and...

www.420magazine.com

Yes, we see magnesium deficiency all the time here at 420mag... and yours is not that. The example you showed is a good one, but it is not what your leaves are doing.

Yeah just don't forget to dilute it. I have red some people, some here and some from other forums, using it directly and just wanted to note the importance of diluting acidic material one more time.

I will share some more leaves tomorrow. Lets decide whether is a Mg deficiency or a fungus then. I will be surprised if the problem turns out to be Mg deficiency as well but some leaves look really similar.

I will try apple cider vinegar and milk formula tomorrow if we agree on fungus after checking further evidence. If I can defeat these spots in 4-5 days with this mix, I won't buy a fungicide from grow shop.

Thanks a lot for your time btw really appreciated

 

[Emilya Green]

it is possible that you have both problems... mag deficiency is extremely common in cannabis grows

 

[TriangleCheese]

it is possible that you have both problems... mag deficiency is extremely common in cannabis grows

Yeah that would be the worst case for me

 

[TriangleCheese]

Btw I defoliated both of my plants and maxed the fan. I lowered RH inside tent from %72 to %57. I have red about Blue Cheese loving high RH and very strong against mildew 7-8 days ago but I guess will keep growing my way. RH around %55 works like a charm for many years. I don't know why I did this. Maybe I got greedy(probably the worst thing you can do when cultivating cannabis) for a second

 

[Aroxol]

I agree with Emilya, that’s not cal or calmag. To me that looks like a molybdenum deficiency if anything nutrient related (if that’s pink?)?

Just for my own education, why did you both think fungus? Does it tend to impact leaf coloration like that?

 

[Aroxol]

And also props for diagnosing weed issues on your DJ gear

 

[Emilya Green]

I agree with Emilya, that’s not cal or calmag. To me that looks like a molybdenum deficiency if anything nutrient related (if that’s pink?)?

Just for my own education, why did you both think fungus? Does it tend to impact leaf coloration like that?

Moly right now is such an extremely trace element that is needed in flower, that it would not show a deficiency at this point in the grow. Mid to late flower is where this will crop up, and almost always is pH related. I thought fungus because it does not seem to be starting from anywhere or attacking a particular point.. it just seems to have landed there.... I thought fungus instead of mold because it is not fuzzy. I would bet that a close examination of the back side of the affected leaves would show a fine white powder.

 

[Hdinkleman]

Just found this on a grow website. Looks just like my leaves. Can it be Magnesium deficiency? I am feeding them with minimal amounts of Advanced Nutrients Cal/Mag. I have increased the amount 4-5 days ago but I cropped more leaves with spots today. I thought FishMix had enough Cal/Mag in it but apparently not. Do you guys think this case is caused by Mg deficiency?

Magnesium (Mg):
-Commonly deficient in Cannabis
-Yellowing of lower leaves progressing upwards with severity
-Interveinal yellowing
-Rust brown patches on leaf margins, tips and between veins

my leaves have/had the same stuff im growing in coco i added calmag the plant is now healthy.
are you adding calmag to your water?

 

[Aroxol]

Moly right now is such an extremely trace element that is needed in flower, that it would not show a deficiency at this point in the grow. Mid to late flower is where this will crop up, and almost always is pH related. I thought fungus because it does not seem to be starting from anywhere or attacking a particular point.. it just seems to have landed there.... I thought fungus instead of mold because it is not fuzzy. I would bet that a close examination of the back side of the affected leaves would show a fine white powder.

Never had it, but saw a plant recently that had the picture perfect pink leaf issue - and happened to be mid-late flower and had pH problems. Think you’re spot on, and thanks for the info on fungus.

 

[TriangleCheese]

I agree with Emilya, that’s not cal or calmag. To me that looks like a molybdenum deficiency if anything nutrient related (if that’s pink?)?

Just for my own education, why did you both think fungus? Does it tend to impact leaf coloration like that?

Molds have fuzzy mycelium look. Just like Emilya said below.

And also props for diagnosing weed issues on your DJ gear

My studio is not "smoke free" I can tell you that

Moly right now is such an extremely trace element that is needed in flower, that it would not show a deficiency at this point in the grow. Mid to late flower is where this will crop up, and almost always is pH related. I thought fungus because it does not seem to be starting from anywhere or attacking a particular point.. it just seems to have landed there.... I thought fungus instead of mold because it is not fuzzy. I would bet that a close examination of the back side of the affected leaves would show a fine white powder.

Thanks again for nice information. Some leaves are already affected and that means I have spores flying over inside my tent. In 1-2 weeks I won't let leaves or branches touch each other, even slightly. I think I don't have a chance to kill all the spores before harvest so I will install more and more air flow. I will also give vinegar mix a try.

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• TriangleCheese
• Mar 5, 2019

IMG_4487.JPG

• TriangleCheese
• Mar 5, 2019

my leaves have/had the same stuff im growing in coco i added calmag the plant is now healthy.
are you adding calmag to your water?

I have been adding Advanced Nutrients Sensi Cal/Mag around 0.5 ml/l. I am also using Biobizz Fishmix, which contains fundamental amounts of Cal/Mag but it might prepared to be at a more suitable ratio for soil rather than coco. I increased the Cal/mag ratio to 1.5ml/l now because I have some leaves with Mg deficiency besides the fungus like Emilya said yesterday.

I will get some vinegar today. I cropped all of the affected leaves and I will be ready if the fungus strikes back.