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"rusty" leaves

chemman14

Member
so my plant is getting ever closer to harvest time and I have noticed that the leaves are begining to turn "rusty" here is a picture of what I am talking about
picture.php

as you can see this isn't really effecting the bud growth
picture.php

any ideas of what this could be? I have been posting a diary of the plant since it entered flowering here
https://www.icmag.com/ic/showthread.php?t=161989
 

TexasToker

Member
I would say magnesium actually or incorrect PH. Almost a picture perfect case IMO. Do you flush your plants with PH'd water? All the leaves that are damaged will not recover. To try and straighten it out flush with PH'd water followed by a gallon with a tsp of Epsom Salts. You can add Epsom to a foliar spray, but since you are already in flower I would not go that route.

pH is very critical to Cannabis. A lot of nutes get locked out with incorrect pH, which can cause other nutes to not be absorbed as well.

Are your leaves crunchy?

Also, it is easier to help if you follow the sticky at the top of this forum so we know what your setup is.
 

chemman14

Member
I would say magnesium actually or incorrect PH. Almost a picture perfect case IMO. Do you flush your plants with PH'd water? All the leaves that are damaged will not recover. To try and straighten it out flush with PH'd water followed by a gallon with a tsp of Epsom Salts. You can add Epsom to a foliar spray, but since you are already in flower I would not go that route.

pH is very critical to Cannabis. A lot of nutes get locked out with incorrect pH, which can cause other nutes to not be absorbed as well.

Are your leaves crunchy?

Also, it is easier to help if you follow the sticky at the top of this forum so we know what your setup is.

I have been using ph down on my water to get it to around 6. I have also been using cal-mag with each feeding
 

hazy

Active member
Veteran
i hate to suggest the 'form' up in the stickies, but if you use it, please put your answers in a different color.

being close to harvest, prolly nothing to stress about.
 

Norkali

Active member
Wow, you want to see something cool? (From a scientific standpoint, not a growers - lol) Look at my Deficiency thread, the same exact problem, but in the exact opposite parts of the leaf, the centers instead of the veins - so interesting!!!

Most likely pH mayne, if your going down to 6, that may be a little low, as cannabis in soil prefers ~6.5-6.6. :tiphat:
 

chemman14

Member
but my mazar that is getting fed with the same ph water is not having the issue. oh well I will check my ph next time I water
 

Norkali

Active member
but my mazar that is getting fed with the same ph water is not having the issue. oh well I will check my ph next time I water

Some plants are 'pickier' when it comes to pH, some can grow just fine with your pH off a bit - others pitch an absolute fit out if you have the pH off even a point or two (like 6.3 vs. 6.5) :blowbubbles:

Also, in my experience I have found that flowering, almost-done plants, tend to be very sensitive to pH fluctuations. Reminds me of my first indoor grow, bagseed, hadn't checked the pH literally all of the grow, added a little guano with like 4 weeks to go, fucked the pH (I'm presuming now that guano is pretty acidic) and all the leaves twisted violently and started yellowing by the next morning - nearly ruined the whole run.
 

FoCo(No.Co)

Barned
Veteran
I think you are feeding/fed it too much NPK and your OG is sensitive, but the Mazar is hearty.

Since you are at day 56, you should just start the flush, man.
 

FoCo(No.Co)

Barned
Veteran
I think you are feeding/fed it too much NPK and your OG is sensitive, but the Mazar is hearty.

Most likely pH mayne, if your going down to 6, that may be a little low, as cannabis in soil prefers ~6.5-6.6. :tiphat:

YES! A slightly too acidic soil with too much potassium(in your grow thread, it looks like you fed a lot of K) will cause Calcium lockout!!!

I would bet a zip that is whats going on here.

EDIT:i'm sorry about the triple posts, i fucked up
 

Norkali

Active member
I think you are feeding/fed it too much NPK and your OG is sensitive, but the Mazar is hearty.

Since you are at day 56, you should just start the flush, man. Using a light solution of Epsom Salt wouldn't hurt.

Wouldn't his tips be crispy if he overfed? The way it is distributed through the leaves makes me think pH...

Edit: Oooh, nevermind, look at those tips in the second picture. I think Fo. Co. may be zeroing in on the problem.

lol, second edit: Yep FoCo - a combination of both probably is exactly what's going on here. Haha, that was awesome :biglaugh::tiphat:
 

chemman14

Member
YES! A slightly too acidic soil with too much potassium(in your grow thread, it looks like you fed a lot of K) will cause Calcium lockout!!!

I would bet a zip that is whats going on here.

EDIT:i'm sorry about the triple posts, i fucked up
hmm, interesting. So should i be adjusting the PH after i add all of my nutes? I have been doing it before adding nutes.
and I will be starting the flush tomorrow. Final phase.
 

chemman14

Member
YES! A slightly too acidic soil with too much potassium(in your grow thread, it looks like you fed a lot of K) will cause Calcium lockout!!!

I would bet a zip that is whats going on here.

EDIT:i'm sorry about the triple posts, i fucked up

so I shouldnt of added that pk boost in the final feeding? or reduced K over the whole feeding schedule
 

Norkali

Active member
so I shouldnt of added that pk boost in the final feeding? or reduced K over the whole feeding schedule

Looks like it might have been a little too much pk boost, try maybe half the mount next round and see how that goes. As far as the K, while I haven't looked through your log, may be at a totally acceptable amount, but you just need to get the pH in check first so you don't experience the same lockout FoCo identified. Yes, and as FoCo said too, this is just my opinion having not read through your thread.
 

chemman14

Member
thanks for spending the time reading my diary. That is one of the main reasons why I have tried to keep it so detailed. That way if i had an issue others could help me pin-point it and I can avoid it on my future grows.
 

FoCo(No.Co)

Barned
Veteran
Yea man, you gave them far too much bloom stuff, too often. You should start with a nice soil that will give your plant what they need for the first couple weeks of bloom, then when you start giving bloom nutrients alternate the nutrient mix with plain water. I'd also use about half of the strength that you used as far as mL/gal is concerned.

Dont feel bad, I fucked up my first grow FAR worse. I would still hit your bud, but make sure you flush the living shit out of that soil before harvest. If you dont, your shit will pop snap and crackle from all the phosphorus.
 

chemman14

Member
Yea man, you gave them far too much bloom stuff, too often. You should start with a nice soil that will give your plant what they need for the first couple weeks of bloom, then when you start giving bloom nutrients alternate the nutrient mix with plain water. I'd also use about half of the strength that you used as far as mL/gal is concerned.

Dont feel bad, I fucked up my first grow FAR worse. I would still hit your bud, but make sure you flush the living shit out of that soil before harvest. If you dont, your shit will pop snap and crackle from all the phosphorus.
yeah I am going to give it near a gallon of prepared final phase and then give it plain water for the subsequent feeding and then harvest. Thanks for the suggestions :D
 
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