How To Identify and Control Septoria on Cannabis Plants

How To Identify and Control Septoria on Cannabis Plants

How To Identify and Control Septoria on Cannabis Plants

Professor DeBacco

Septoria Identification
Septoria leaf spot can cause leaf loss and reduction in photosynthesis and is one of the most common leaf spot pathogens among the hemp leaf spot diseases.
Scout lower leaves and within the inner canopy where leaf wetness and high humidity occur as this is the likely place for the disease to start.
Look for small irregularly shaped spots with bright yellow margins.  Spots expand to about ¼ inch in diameter and appear brown with a prominent yellow halo. 
As spots enlarge, brown areas become more irregular and develop gray to white centers. 
Yellow halos expand outward from spots. 
Entire leaves rapidly become yellow and drop from plants in advanced cases.

Septoria Life Cycle

Septoria Management
When excess moisture or high humidity is available, fungal life cycles are shorter, and larger numbers of spores are produced. So this can increase the chance of disease later in a plants life cycle when the plants are more dense. During rainy summers, disease can spread rapidly through fields.

Septoria species can overwinter in fields on infected plant debris as pycnidia.
Under cool conditions with low relative humidity, pycnidia may remain viable for up to 9 months in debris.
In contrast, pycnidial survival decreases dramatically in hot weather or when buried in soil (i.e. tilling), to less than one month.

Although alternative hosts have not been identified for the Septoria species that causes leaf spot in hemp, it is likely that weeds or another similar “green bridge” is responsible for survival from one growing season to the next.

Link to Lecture Slides: https://drive.google.com/file/d/1kWtPgsIuqnWe6zSt1_539B3-KP9_FC6z/view?usp=sharing

*Due to the description character limit the full work cited for “How To Identify and Control Septoria on Cannabis Plants” can be viewed at… https://drive.google.com/file/d/13IfNnUwTLHrX1f3Q63LfyLbLQ9EWpB-l/view?usp=sharing

41 Comments

  1. Tripppy on January 15, 2023 at 1:22 pm

    is it ok smoke the plant with a desease like this?



  2. Bread on January 15, 2023 at 1:22 pm

    🤦🏻‍♂️ I definitely have this problem. I’m glad I randomly come across this video! I’ve been thinking it was a nutrient problem this whole time. Now I can hopefully eradicate the issue and prevent it in the future! Thank you



  3. Yonder Mountain Jam Fan on January 15, 2023 at 1:23 pm

    This video was lacking in strategies to combat existing infections. Prevention is the best, but omitting treatment recommendations left many of us looking elsewhere.



  4. Mark Redwood on January 15, 2023 at 1:23 pm

    Thanks



  5. Jesse Freeman on January 15, 2023 at 1:23 pm

    Thank you… so many people think they have nut deficiency…. I will be sharing this video..



  6. Ronald Tharp on January 15, 2023 at 1:24 pm

    I did not hear you say anything about how to get rid of it



  7. Vince Callagher on January 15, 2023 at 1:24 pm

    Did you said you were going to tell us how solve this. Guess you are saying get rid of humidity? Kinda hard outside.



  8. webo420 on January 15, 2023 at 1:26 pm

    Now i know why my plants repeatedly get it. Looks like I’m doing soil maintenance after harvest.



  9. KING FISH / PHILL on January 15, 2023 at 1:28 pm

    Very good information and understandable , great video and footage 😎



  10. Newwavepressure on January 15, 2023 at 1:28 pm

    Can I do a foliar spray with some hydrogen peroxide



  11. Robert the Grow Guy on January 15, 2023 at 1:30 pm

    Looks alot like a type of blight unless septoria is like a Latin term for blight



  12. Lydia Hilles on January 15, 2023 at 1:31 pm

    My plant was placed by a small black walnut tree(i think) which unknowingly had leaf spot. It wasn’t there last night and is this morning. Its been raining the last 2 days😢 so quick i didn’t see it coming.



  13. Ponolovefarms on January 15, 2023 at 1:35 pm

    Liquid copper



  14. Levi Chicwown on January 15, 2023 at 1:37 pm

    I know this is a little late, I have my cannabis plant but its not leaf septoria, its some weird spots that looks like rust at the base of some leaves while I can see regular healthy ones have no visible spot at the base. I don’t know if this will affect it in anyway but it seems to not be spreading so? Should I be worried



  15. Cody Henry on January 15, 2023 at 1:41 pm

    Hydrogen peroxide might combat this well🤔



  16. Jahstafari on January 15, 2023 at 1:42 pm

    Tnx ….i think i have it on one plant …i thought it was some soil problem creating root problem ….causing deficiency ….can hydrogen peroxide spraying eliminate patogen?



  17. Technically Infinite on January 15, 2023 at 1:46 pm

    So far I really like your content. You give clear descriptions of the things you are talking about(/w pics), and you haven’t tried to ramble off technical jargon, in a way to make yourself seem knowledgeable. I just started growing myself and of all the 100’s of hours of youtube growing content i’ve watched, yours is my favorite so far. You actually describe everything properly without seeming biased toward certain methods while clearly stating the reasons why. What I like the most of all is all the trouble shooting you show for the different diseases/ deficiencies, etc.



  18. Paul G on January 15, 2023 at 1:48 pm

    I had these spots on a yam vine’s lower leaves and it was apparently anthracnose, a fungus treated with copper, I removed the leaves and it seems to have disappeared for now.



  19. Shanne Lowe on January 15, 2023 at 1:48 pm

    Looks like liver spots on older people lol



  20. Nahledge Bourne on January 15, 2023 at 1:49 pm

    I am a mycologists. And thru my experience the best combatant in a situation like this would most likely be a beneficial bacteria. Lacto basillus would probably do a pretty decent job of attacking this fungas while keeping the plant remaining plant material unaffected



  21. Pastrie Ryan on January 15, 2023 at 1:50 pm

    I loved how you covered prevention. I just wish you would have covered the control a lot more. Are there any sprays? Do you remove the affected leaves? These are pretty important things that people watching this video are trying to find out. Cheers. That being said you still taught me things, which I’m grateful for!



  22. pappy van winkle on January 15, 2023 at 1:50 pm

    I.take rice soak in water take the water add molk put in glass jar cover paper towel let srt 3days take top curd off strain the liquid in to another jar i use this at around 2tbsp per galon water works im in Hawaii very humid



  23. Hyperparasite 🌏 Organic Farming 🟢 on January 15, 2023 at 1:54 pm

    Adaptive cultivation of hyperparasites – possible method for controlling pathogens and insect. If you are interested💹



  24. Matthew Molina on January 15, 2023 at 1:56 pm

    I have two autos that are like this I moved them out side from inside weeks ago photo plants in same tent didn’t have this Does this stunt the growth and development ? 1 auto is almost finish the other is at 11 weeks and just started flowering . Thought I was getting multiple deficiencies , is it treatable or should I cut my losses and cull the 11week auto ?



  25. chris tinkham on January 15, 2023 at 1:59 pm

    Is this a outdoors only issue or can it happen indoors



  26. need to know on January 15, 2023 at 1:59 pm

    ok… this is the first season that i have that issue … how do i get rid of it…??



  27. robmarz1 on January 15, 2023 at 2:02 pm

    I have this problem but with only one strain(blue haze). I’m wondering why it never happens to other strains I grow right next to the blue haze plants?



  28. Joe T. on January 15, 2023 at 2:03 pm

    Hey man! Great video! I’ve got septoria doing a number on my plants right now! I was given sulfur dust to treat it as a foliar spray, but 2 days later, it still seems to be spreading. I’ve been trying to remove the affected leaves but it’s spreading pretty fast. Any tips?



  29. Jordan Luke on January 15, 2023 at 2:04 pm

    Debaockle



  30. The grow bro on January 15, 2023 at 2:07 pm

    When you have one that is 8 weeks into flowers does this affect the smokability of the plant as in is it dangerous to smoke the flower since it’s a fungus



  31. Mr Nobody on January 15, 2023 at 2:09 pm

    I’ve got these on top leaves??



  32. Dan O on January 15, 2023 at 2:09 pm

    Gotta get that deep clean. Especially between grows!



  33. Copper Ridge Grow on January 15, 2023 at 2:09 pm

    It’s almost like tomato plant blight. It’s impossible to control. It’s prevalent here in Southwest, Va. If it’s damp it will show up in late august/early September. It doesn’t matter what preventative measures you take. I’ve fought this stuff for 3 seasons.



  34. Swayze Crazy on January 15, 2023 at 2:10 pm

    I have this issue after i gave them my homemade compost tea. It was bubbling for over a week. Got very thick. Ppm was 580. Ph was 8. I use this tea to lower the acid in the soil that the plant makes. But i seen to have dying out leaves. Making it look like a P problem.
    Then rust on leaves and tops have black spots.
    My clones had issues while the main ladies were fine. Till after the light switch. Also had issues. Was thinking light stress. Can’t seem to get it right. Inside temp is 25 c and humidity is 55 percent.



  35. Timmer on January 15, 2023 at 2:11 pm

    Oh no. I think I found it.



  36. Jason Ivy on January 15, 2023 at 2:13 pm

    Do you recommend stripping infected leafs



  37. Drugs Anonymous Intervention on January 15, 2023 at 2:17 pm

    So once your plant gets this your pretty much fucked. Great, my plants have this and they just started budding 🤦‍♂️



  38. Matty itto on January 15, 2023 at 2:18 pm

    My heart is broken, had a beautiful Colombian haze plant, stupid ass septoria is destroying it very rapidly, i thought PM was bad, septoria is very aggressive if you spot it act immediately and cross your fingers, its a devastating disease , my poor haze plant had at least 8 weeks left no way in hell is it gonna make it, be careful out there esp with longer flowering varieties



  39. T H on January 15, 2023 at 2:19 pm

    Bacillus amyloliquefaciens ( southern ag biological fungi ) at 5-15ml per gal, best ag grade biological for leaf spot/septoria



  40. Mike Foglestine on January 15, 2023 at 2:20 pm

    You said nothing about how to help or cure a plant that has this issue. This is more of a recognizing Septoria video.



  41. Dan Dan on January 15, 2023 at 2:21 pm

    Your videos are always very informative