Royal Queen Seeds
royalqueenseeds.com › blog-leaf-septoria-yellow-leaf-spot-on-cannabis-plants-n678
Leaf Septoria and Cannabis: Prevention & Treatment - RQS Blog
November 8, 2023 - Depending on the plant affected, septoria can damage the harvest, or totally destroy it. In cannabis cultivation, it shouldn’t totally ruin a harvest, but it is likely to stunt growth and reduce the final harvest if left untreated.
fungal plant pathogen
Wikipedia
en.wikipedia.org › wiki › Septoria_cannabis
Septoria cannabis - Wikipedia
October 3, 2024 - Septoria cannabis is a species of plant pathogen from the genus Septoria that causes the disease commonly known as Septoria leaf spot. Early symptoms of infection are concentric white lesions on the vegetative leaves of cannabis plants, followed by chlorosis and necrosis of the leaf until it ...
Leaf Septoria? It's been hot and humid.
Could be, maybe deficiency. Pull all the affected leaves and hope it doesn’t come back. Cut down your cottonwood trees. More on reddit.com
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July 26, 2022Is this septoria and is there a way to cure it while my plant is in flower?
Looks to me more like a calcium deficiency than septoria...they can look pretty similar. Might want to include something like gypsum or oyster shells or lime or bone meal next round...calcium is crazy important. Throw a little milk to her roots see if she don't get a Lil happy More on reddit.com
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December 28, 2023Is this leaf septoria and if so is there anything I can do about it during flower?
if you are confident it is not a root zone issue (ph lockout, roots too wet for too long) then i’d wager it’s calcium related, you did not list calcium as one of your nutrient additions so this would make sense…. cannabis is a calcium liking plant and the leaf symptoms are similar to the signs of calcium deficiency. https://www.growweedeasy.com/cannabis-plant-problems/calcium-deficiency you won’t fix already affected leaves and you’ll likely suffer some stunting given how it’s progressed. this will most likely affect yield but now you know for next grow. i don’t personally ph in ffof, i run filtered tap water and fox farm trio with a very light dose of calcium/magnesium in each feeding as a preventative versus a treatment. More on reddit.com
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December 28, 2023Is this leaf septoria? Just harvested and buds look great. Will this make it toxic to smoke?
Buds ruined you'll have to send it to me for analysis
More on reddit.com 4
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June 27, 2019Grow Weed Easy
growweedeasy.com › home › plant problems › leaf septoria / yellow leaf spot
Yellow Leaf Spot (Leaf Septoria) & Cannabis - Get Rid of It Quickly!
Sometimes called “yellow leaf spot” or “leaf septoria,” this condition is caused by a fungus (or sometimes a bacteria) that attacks cannabis plants and usually appears in warm, wet weather.
Dutch Passion
dutch-passion.com › home › blog › cannabis plant › cannabis leaf septoria vs calcium deficiency
Cannabis Leaf Septoria vs Calcium Deficiency | Dutch Passion
Cannabis leaf Septoria is a fungal disease that affects cannabis plants, as well as plenty of other species including tomatoes, potatoes, parsley, aubergine/egg plant and many others.
GrowDiaries
growdiaries.com › journal › what-is-cannabis-leaf-septoria-and-how-to-treat-and-prevent-it
What is Cannabis Leaf Septoria and How to Treat and Prevent It?
November 10, 2022 - Once it takes hold of the lower leaves, it starts moving upwards quickly, leading to various light-colored patches on the higher leaves, too. The affected leaves soon turn yellow and, if not treated in time, turn brown and wither completely. Leaf septoria in cannabis goes beyond just yellow leaves — it damages the rest of the plant in many ways.
Canvast Supply Co.
canvastsupplyco.com › home › the canvast blog › the canvast blog
Identify and Treat Septoria Leaf Spot in Hemp Plants
August 17, 2020 - What is Septoria Leaf Spot Septoria cannabis is a species of plant-pathogen from the genus Septoria, which is an ascomycete and pycnidia producing fungus, otherwise known as Septoria leaf spot.
Kannabia
us.kannabia.com › how-to-identify-and-treat-septoria-leaf-spot-in-cannabis-plants
How to Identify and Treat Septoria Leaf Spot in Cannabis Plants - Kannabia
April 17, 2024 - For example, Septoria lycopersici, ... the spot on wheat, affecting it and also oats, barley and rye. Septoria cannabis is known to cause disease only in cannabis....
FloraFlex
floraflex.com › blogs › floraflex-media › how-to-treat-and-prevent-cannabis-leaf-septoria-a-comprehensive-guide
How to Treat and Prevent Cannabis Leaf Septoria: A Comprehensive Guide – FloraFlex
April 18, 2023 - One of the most common ailments that can affect cannabis plants is cannabis leaf septoria. This fungal disease is characterized by small, circular lesions on the leaves that can grow and merge, eventually leading to the death of the plant.
I Love Growing Marijuana
ilovegrowingmarijuana.com › home › grow guides › leaf septoria on marijuana plants
Leaf Septoria On Marijuana and Weed Plants: How to Prevent It
February 17, 2024 - Yellow leaf spot, also known as leaf septoria, are caused by Septoria cannabis and S.
LeafWorks
leafworks.com › home › blogs
The Challenge of Septoria in Cannabis Cultivation - LeafWorks
May 16, 2025 - While Septoria species are well-known pathogens in other agricultural crops (particularly tomatoes), the cannabis-specific variant presents unique challenges to growers. One significant concern is misdiagnosis.
PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC11369300
Septoria cannabicola, a new species on Cannabis sativa from Japan - PMC
Septoria leaf spot on hemp has re-emerged with increasing hemp cultivation worldwide. In Japan, Septoria cannabis, initially recorded as the causal pathogen in Japan, was studied with morphology based on the current criteria and detailed molecular phylogenetic analyses using seven gene loci.
Uky
plantpathology.mgcafe.uky.edu › files › ppfs-ag-h-01.pdf pdf
Importance Septoria leaf spot is the most commonly reported leaf
Septoria leaf spot is caused by Septoria cannabis. In · general, Septoria spp. infect specific hosts or a specific · group of hosts. For example, Septoria lycopersici, causing a leaf spot of tomato, affects tomato and other
Farmonaut®
farmonaut.com › home › precision farming › organic treatment for cannabis & tomato septoria leaf spot
Organic Treatment For Cannabis & Tomato Septoria Leaf Spot
June 18, 2025 - While we promote organic methods, we recognize that conventional fungicides can be effective in severe cases of Septoria Leaf Spot. Some common chemical treatments include: ... Note: Always follow label instructions and local regulations when using chemical fungicides, especially on edible crops like tomatoes or medicinal plants like cannabis.
Growers Choice Seeds
growerschoiceseeds.us › home › leaf septoria in cannabis plants: prevention & treatment
Leaf Septoria and Cannabis Plants | Growers Choice Seeds
January 26, 2026 - This disease specifically targets cannabis plants, among others, making it a concern for both outdoor and greenhouse growers. The fungus thrives in warm, wet conditions and is particularly prevalent in places with high humidity or during rainy seasons. Leaf septoria affects the foliage of the plant but does not typically affect the buds directly; however, it can significantly impact the overall health and yield of the plant if you don’t manage it properly.
Humboldt Seeds
humboldtseeds.net › blog › grow tips › septoria: with yellow spots in sight, keep your plants dry
Septoria: with yellow spots in sight, keep your plants dry - Humboldt Seeds
Septoria, also known as "leaf spot disease", is caused by a fungus that attacks cannabis plants and usually appears outdoors with frequent rain and hot climates. Over 1000 species of pathogens can lead to this fungal disease, each infecting ...
Herbies Seeds
herbiesheadshop.com › blog › leaf-septoria-an-in-depth-guide-to-yellow-spots-on-cannabis-leaves
Leaf Septoria – An In-Depth Guide To Yellow Spots On Cannabis Leaves - Herbies Seeds USA
May 18, 2020 - This fungus is known for originating ... abundantly in outdoor environments. When transferred to cannabis, leaf septoria causes unnecessary stress and hinders the overall growth of the plant....
PubMed
pubmed.ncbi.nlm.nih.gov › 33719542
Reemergence of Septoria Leaf Spot Caused by Septoria cannabis on Hemp in Kentucky - PubMed
Hemp reemerged in 2014 after being ... is primarily grown for production of cannabidiol (CBD), with limited acreage dedicated to fiber. One of the most frequent and destructive leaf spot diseases of hemp cultivars grown for CBD is Septoria leaf spot...
Growers Network
growersnetwork.org › home › growers network’s disease profile: septoria leaf spot
Growers Network’s Disease Profile: Septoria Leaf Spot - Growers Network
November 5, 2019 - The Septoria cannabis species however is limited to infecting hemp and Cannabis only. As seen above, it is characterized by causing yellow-white circular spots to appear on the leaves.
Plant Health Progress
apsjournals.apsnet.org › doi › 10.1094 › 9780890546284.02.17.1
Septoria Leaf Spot | Compendium of Cannabis Diseases
September 13, 2022 - Two Septoria species have been reported on Cannabis sativa: S. cannabis and S. neocannabina. The specific distribution of each species is unknown, since morphological characteristics are similar between them, but S. cannabis appears to be dominant in cannabis production in the United States.