A little help with rusty leaves!


I’ll Try to keep this short and sweet. I have four different strains in a 4 x 4 grow tent with a 400 W HPS. Coco, general hydroponics flora nova bloom, big bud additive and Cali magic. One of the plants, my pure Indica it’s starting to get brown discoloration it looks like rust on the leaves. I’ve never done the whole pH thing before so I don’t know what the pH is but it’s never been an issue for me in the past and the other plants are fine.

If anybody tell me, typically, what is the issue with the leaves when they look all rusty? More importantly what can I do to fix it? I got about one more month of flowering to do on these.


Ph, cal/mag and possibly phosphorus deficient, based upon the purple stems. Those are the most common reasons for leaves looking like that. Could be a combination of a few of those. If you’re not checking ph, I’m gonna start there.


I’d say that’s pretty accurate. Nutes can be there, just not being consumed by plant due to ph.


Maybe you can fill out this!
COPY/PASTE: This “Support Ticket” into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, or NA

Soil in pots, Hydroponic, or Coco?

System type?

PH of runoff or solution in reservoir?
What is strength of nutrient mix? EC, or TDS

Indoor or Outdoor
Light system, size?

Temps; Day, Night
Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, No
Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you



Thank you for posting the Support Ticket.

For one he needs a ph meter. With out one it’s a guessing game.
I’em leaning toward fungus cause that’s what rusty brown on leaves is it’s a fungus ands needs to be treated that way.

rust, how many of you have had this and been beaten by it? lots i bet!!!
first, rust is a fungi. it is opportunist. it preys on unwell plants. if something is a miss, rust is a sign. rust has been identified to have 7,000 species. it attacks crops of every description. but we’re only interested in one variety arn’t we?
if rust is present early in a grow, you have problems as it’s an indicator something in your room is a miss. usually ventilation. go through your system and double check things are in place and working properly.
rust is an air borne fungi. if given the opportunity, it WILL take hold. it usually does during flower as this is when the plants immune system is at its weakest as its energies are concentrating on re-production, not survival.
depending on what part of the grow you get it, you can cure/minimize it with either chemical or natural remedies.
it enters the leaf via the stomata and then it’s off and running.
fungacides used are generally copper based and include; thriram, manzecob, maneb or zineb at 10 day intervills.
baking soda, 1 tea spoon/ quart of water. spray on.
copper sulphate, read lables.
fungacidal soap sprays;
garlic sprays, 1/2 cup minced garlic, 1 quart of water. let sit 24hrs, strain, spray.
sulphur, one of the best natural sprays. it is low in toxicity.
micro kill, a citric based killer. i use this with great success


I used sulfur. Just cleaned it off today with a watering can. Still left white dots on some darker leaves.
I put mine into fruiting mode yesterday, so I’ll be watching and picking off any more. I had a couple leaves today with the tips leaves dried up and a tad brown. Doesn’t look like the original issue. Usually the center leaf of the five, and brown in the middle, not dried up. I just kept plucking them, tried the CaliMag for a few weeks, and then dusted with sulfur powder. Tell me this, can you still smoke, vape, or cook with it if it has a little left at harvest time, or in a bud where I can’t see it?



How ya doing today ?
The tips that are brown kinda burnt is a sign of " NUTRIENT BURN " Here is a pic of it. It
starts at the tip and spreads to the sides as you can see… Stop with the nutrients and water only for the next 3 waterings ok


Thanks G-Man. Mine were just on the center leaf tips. Have been feeding with Humbolt Grow, and CaliMag at the PH of 6.25. So maybe a touch over over nute.
I’ll skip the nutes for a few weeks, and start the Humbolt Bloom.
I’m pretty good. You?



I’m fine thank you. Just getting over the flu



Heard this year’s was a rough one. Will, if I pluck any brown leaves will my crop be okay to smoke this harvest?



I don’t see why not. I’m always taking the leaves off that are old and used up by the plant.


Looks like I’ll be a little more picky this harvest…:expressionless:


Okay to use the organics during fruiting mode (pre-bloom) and leave it on?
The sulfur took care of all but on plant.



That’s good to hear.
Let me know how your harvest go’s…ok



You got it. See the latest picture I posted. Weighing the difference between growing and buying outright now that it’s legal here.
Also, I noticed no tips on cloning. Will that pull too much biz away from ILGM?



No it sure won’t. can’t wait to see your harvest. This is where your patience will be tested big time…lol

Will meatballs


Patience I got. On month five. I have a seven month deadline last (and first) grow. They could have gone at least two to four weeks longer. I was just getting into checking out the triclomes (sp?).
They were just turning amber.