Septoria cannabis - FUNGUS HELP

OK - I’m about 6 weeks into flower on an outdoor grow. I’ve got 4 varieties (6 plants) over 2 grow sites, both of which are affected similarly. After hours of research, I am fairly certain I have a severe case of Septoria cannabis fungus. This is a damn shame. I’ve moved past the four-lined plant bug attack earlier in the season. Although I lost a few substantial limbs during EXTREME winds we’ve had recently, most were saved by bamboo staking . 10 days or so ago, my ladies were in near perfect health, standing 9’ tall, 8’ wide, and flowering nicely. around 10 days ago, we began to get pounded with rain. every day… rain…rain…wind… rain…wind… In my reading, I discovered that this is the perfect condition for Septoria cannabis fungus to arrive and spread. It spread like wild fire. I could almost notice deterioration by the hour and not day. I realize that the damage is to a point where I’ll incur substantial loss of quality and yield. I guess what I’m looking to do (without driving myself nuts…lol) is to salvage what can be salvaged, and move forward best I can. If anyone is familiar with this issue, or can concur my suspicions of Septoria cannabis fungus are correct, please give me your insights. Assuming that is the issue, I see only a few options

  1. do nothing to combat the fungus. hope that the flower production can “out run” the destruction of the plant / flowers. possibly harvest early would be prudent?

  2. neem oil or some other fungicide? everything I read says not to do this in flower stage. will ruin flavor and smokability.

  3. let them flower until trichomes and pistils indicate it’s time to harvest? I will say, that the more affected plants have more pistils turning red faster that I think they should, whereas the more heathy ones are mostly white as they should be at this stage.

In any case, do I have a chance at a decent harvest, or should I write this off as one big and painful learning experience, and move on to preventative measures next year.



Definitely try to remove all infected leaves while following strict protocols to prevent cross-contamination. Clean up all weeds and dead stuff on the ground.

Try a broad spectrum fungicide, one with Copper would be extremely effective. Neem oil, eucalyptus, rosemary, lemon, and cinnamon could help, too, but they could affect flavor. Try to avoid spraying your buds. No matter, you will definitely want to wash any buds you harvest, to remove the residue of whatever you apply.

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That looks scary :frowning: . Spraying fungicides will not help once your plant is affected , most fungicides are used to prevent spores on the surface to penetrate to plant tissue , once they are in the system you can just work on the environment to stop their spreading , but since you are outdoor is tricky :@ Maybe someone with Septoria experience , but it looks like Septoria …

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You could try something like enzyme komplete natural cleaner. Do a wash with it all over the plants and rinse about a 1/2 hour later should help. Do NOT let it sit on the plants for a long time. This will remove the spores that is causing your problem. It will not repair the damage already done. Like others have remove the damage leaves after treatment.


Thank you for the replies~! well, the fungus has progressed at a rapid rate. I’ve decided not to drive myself nuts picking and cleaning the area… that would’ve been a full day’s work as well as being eaten alive by mosquitos and other fun bugs! I also did not apply anything to them, as I didn’t want to take chances with ingesting anything toxic or messing with natural flavors…

I have decided to leave it in Mother Natures hands, and see what can be salvaged. I will attempt to time it out and harvest what I can. some is worse than others. many of the more severely affected plants have lost ALL LEAVES. The necrosis (fungus) has even crept into the flowers to some extent. I don’t expect much more growth, as foliage is mostly destroyed. My final question on this is:

will smoking these flowers pose any threat? are they at all toxic? I have much more work to do in harvesting, manicuring, and curing… many many hours it will take, as you all know. Some of the tops actually look worth while, but many have been stunted. they aren’t nearly as fat and full as they surely would have been if plants remained healthy. I have researched on whether or not its safe to smoke, and I cant find one single paragraph on this! Again, I firmly believe this is a SEVERE case of Septoria cannabis fungus. I say severe, as most info indicates attack of foliage only, with reduced yields… I just need to know if its safe to smoke or not at this point. I will post some pics later, but feel free to leave opinions. thanks!!!

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here are the pics… please tel me this will not be toxic or harmful to salvage, process, and SMOKE??? SO DISGUSTED

OMG! That is just TERRIBLE! Damn what shitty luck. Ok i have to go now i cant look at THAT any more.:hot_face::disappointed_relieved::sleepy::cry::sob::scream: R.I.P.
They were such young buds and were just enjoying life. When there lives were tragically cut short by complications from septoria cannabis. We will forever remember them as they were and what happy lives they lived and they touched us all why they were with us and will be remembered forever. Godspeed little buds.:pray::angel:


The life of an outdoor grower…

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Yep i have to fight. Earwigs, grasshoppers, and Deer.

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I have seen plenty of extracts made from contaminated plants (remove most dead material first) it was tested before donation to medical patients.(we were all ok after;) if it was mold id say throw it .


Lol @hoppiefrog we were all ok lol made me laugh a lot ha ha.

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