Is your cannabis plant looking unhealthy? Diagnosing problems early is crucial for a successful grow. Use this visual guide and interactive tool to quickly identify what’s ailing your marijuana plants and learn how to fix it. Click on the images below to explore common cannabis plant problems, deficiencies, and symptoms, and find effective solutions.
Having trouble pinpointing the issue? Consult our 5-Step Remedy to 99% of Cannabis Growing Problems for a comprehensive approach.
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Browse through these cannabis plant symptoms to narrow down your diagnosis:
Accidental Re-Vegging
Accidental re-vegging happens when a flowering cannabis plant reverts back to the vegetative stage. This cannabis plant problem leads to unusual new growth and leaves with smooth edges as the plant tries to revert to its vegetative state after flowering has begun. This is often triggered by light cycle disruptions. Read More
Aphids
Aphids are common cannabis pests, small soft-bodied insects that come in various colors such as white, green, yellow, black, brown, and red. They are typically found under cannabis leaves and are often accompanied by white specks, which are baby aphids and their exoskeletons. Aphids suck sap from cannabis plants, weakening them. Read More
Barnacle Scales
Barnacle scales are unusual, immobile bugs that can infest cannabis plants. These scale insects attach themselves to stems and undersides of leaves, resembling barnacles. They are stationary and suck vital fluids from the plant, causing stress and reduced growth. Regular inspection helps in early Cannabis Plant Diagnosis. Read More
Beet Curly Top Virus
Beet Curly Top Virus (BCTV) is a serious cannabis plant disease. Symptoms include curling and twisting leaves, noticeable yellowing, and overall stunted growth. This virus can severely impact cannabis health and yield. Early cannabis plant diagnosis is key to manage the spread and impact. Read More
Boron Deficiency
Boron deficiency in cannabis, though rare, can occur, especially in underwatered plants or dry environments. This nutrient deficiency manifests as brown patches on cannabis leaves and leads to thick, twisted, or otherwise abnormal new growth. Proper watering and environmental control are crucial to prevent this cannabis nutrient deficiency. Read More
Broad Mites
Broad mites are microscopic cannabis pests, virtually invisible to the naked eye. Broad mites cause significant damage indicated by droopy or twisted new growth, particularly at the top of the plant. Leaves may appear blistered and glossy. Accurate cannabis plant diagnosis requires a magnifying tool to identify these pests. Read More
Bud Rot or Mold
Bud rot, or mold, is a devastating cannabis disease caused by fungal infections. It’s especially prevalent in dense buds in humid conditions. Signs of bud rot include dying leaves appearing within the buds themselves. Early cannabis plant diagnosis and intervention are vital to save the harvest. Read More
Calcium Deficiency
Calcium deficiency is a cannabis nutrient deficiency that leads to brown spots on the leaves. Calcium is essential for plant structure and stress resistance. Identifying these spots during cannabis plant diagnosis can help growers correct nutrient imbalances and improve plant health. Read More
Caterpillars & Inchworms
Caterpillars and inchworms are cannabis pests that cause noticeable damage. These pests eat cannabis leaves, leaving holes and missing chunks. Finding such damage is a clear sign of infestation during cannabis plant diagnosis, prompting immediate pest control measures. Read More
Copper Deficiency
Copper deficiency in cannabis is indicated by unique leaf symptoms. Cannabis leaves become dark, almost shiny, with blue or purple undertones. Leaf edges and tips turn yellow. Recognizing these visual cues is vital for accurate cannabis plant diagnosis and nutrient correction. Read More
Crickets
Crickets are opportunistic cannabis pests that can damage plants by eating leaves, leaving small holes. Mole crickets may also disturb roots by digging in the soil. Identifying cricket damage is part of effective cannabis plant diagnosis and pest management. Read More
Four-lined plant bug
Damage from four-lined plant bugs on cannabis is often mistaken for leafhopper damage. These pests cause specific leaf damage with distinct spotting patterns. Proper cannabis plant diagnosis distinguishes this damage from other pests, ensuring targeted treatment. Read More
Fungus Gnats
Fungus gnats are tiny flying cannabis pests, often appearing as small flies buzzing around the soil surface. They thrive in wet soil conditions. The presence of fungus gnats indicates overwatering or poor drainage, essential factors in cannabis plant diagnosis and environmental management. Read More
Grasshoppers
Grasshoppers and locusts are larger cannabis pests that consume leaves, leaving significant holes. Grasshopper damage is easily identifiable due to the size and irregular patterns of eaten areas on cannabis leaves, crucial for cannabis plant diagnosis. Read More
Heat Stress
Heat stress affects cannabis plants exposed to excessive temperatures or light. Cannabis leaves react by cupping upwards, trying to reduce light absorption and heat. Leaf curling is a key symptom for cannabis plant diagnosis related to environmental stress. Read More
Hemp Russet Mites
Hemp russet mites are minute cannabis pests that are very difficult to see. They cause significant damage, with symptoms including yellow masses of bugs and drooping plant tops. Early cannabis plant diagnosis is challenging due to their size, but plant symptoms are indicative. Read More
Hermies, Pollen Sacs & Bananas
Hermaphrodite cannabis plants develop both male and female sex organs. Pollen sacs (“bananas”) are a sign of hermaphroditism. Identifying these during cannabis plant diagnosis is critical for preventing self-pollination and seed production in female-intended grows. Read More
Iron Deficiency
Iron deficiency in cannabis typically manifests as bright yellowing on new leaves, especially inner and upper leaves. This cannabis nutrient deficiency impacts new growth most severely. Cannabis plant diagnosis involves checking new growth for these distinctive yellowing patterns. Read More
Leaf Miners
Leaf miners are cannabis pests that live within leaf tissue. They create pale, winding trails on cannabis leaves as they tunnel through. These distinctive trails are key to cannabis plant diagnosis for leaf miner infestations. Read More
Leaf Septoria / Yellow Leaf Spot
Leaf septoria, or yellow leaf spot, is a cannabis disease caused by fungi or bacteria. It presents as round yellow or brown spots on cannabis leaves. Identifying these spots is important for cannabis plant diagnosis to differentiate from nutrient deficiencies. Read More
Leafhoppers
Leafhoppers are cannabis pests that feed on leaves, causing brown or yellow spots. They can also transmit plant diseases. Spotting leafhoppers or their damage is crucial for cannabis plant diagnosis and preventing further infestation and disease spread. Read More
Light Burn or Light Stress
Light burn or light stress occurs when cannabis plants receive excessive light. Symptoms include yellowing leaves or leaf tips, particularly those closest to the grow light. This is a common environmental issue in cannabis plant diagnosis. Read More
Magnesium Deficiency
Magnesium deficiency in cannabis starts with light green or yellow coloring between veins and edges of older, lower leaves. This cannabis nutrient deficiency progresses if unaddressed. Cannabis plant diagnosis includes checking lower leaves for this interveinal chlorosis pattern. Read More
Manganese Deficiency
Manganese deficiency in cannabis leads to yellowing between leaf veins, accompanied by mottled brown spots. These brown patches are crucial for cannabis plant diagnosis, differentiating it from other deficiencies. Read More
Mealybugs
Mealybugs are white, hairy cannabis pests that thrive in warm conditions. They appear as white patches resembling mold or webbing on cannabis plants. Identifying these bugs is essential for cannabis plant diagnosis and initiating pest control. Read More
Molybdenum Deficiency
Molybdenum deficiency in cannabis can initially mimic nitrogen deficiency with yellowing lower leaves. However, it uniquely progresses to cause red or pink coloring on leaves. This color change is a key indicator for cannabis plant diagnosis. Read More
Nitrogen Deficiency
Nitrogen deficiency in cannabis is common, causing older, lower leaves to turn yellow, wilt, and eventually fall off. This cannabis nutrient deficiency is easily identified by the progressive yellowing from the bottom of the plant upwards in cannabis plant diagnosis. Read More
Nitrogen Toxicity
Nitrogen toxicity in cannabis is caused by excessive nitrogen. Symptoms include dark green, shiny leaves with clawing or downward-turned tips and slow growth. Recognizing these signs during cannabis plant diagnosis helps in correcting nutrient imbalances. Read More
Nutrient Burn
Nutrient burn, or fertilizer burn, is a frequent issue, especially for beginner cannabis growers. It’s caused by over-fertilization, leading to yellow or brown burnt leaf tips. Identifying burnt tips is a key part of cannabis plant diagnosis for nutrient management. Read More
Over-Watering
Overwatering cannabis leads to droopy and wilting plants soon after watering. Overwatered leaves often feel firm and curl downwards. Drooping after watering is a primary symptom in cannabis plant diagnosis for watering issues. Read More
pH Fluctuations
pH fluctuations disrupt nutrient uptake in cannabis, causing brown spots, particularly on middle and lower leaves. Managing pH is crucial for nutrient availability. Brown spots due to pH issues are important to recognize in cannabis plant diagnosis. Read More
Phosphorus Deficiency
Phosphorus deficiency in cannabis usually appears on lower, older leaves. Leaves develop dark splotches and may eventually drop. Identifying these dark spots on lower leaves is key for cannabis plant diagnosis of phosphorus deficiencies. Read More
Planthoppers
Planthoppers are cannabis pests that leave a unique cotton-like, white fuzzy growth on plants. They suck sap, weakening the plant. These white patches are distinctive in cannabis plant diagnosis for planthopper infestations. Read More
Potassium Deficiency
Potassium deficiency in cannabis causes burnt leaf tips and edges, along with yellowing between leaf margins. Symptoms often appear on older leaves but can occur elsewhere. Burnt edges and yellowing are key indicators for cannabis plant diagnosis. Read More
Root Problems
Root problems in cannabis manifest in many ways, mimicking other issues. Symptoms include drooping, curling, wilting leaves, and slow growth. Due to varied symptoms, cannabis plant diagnosis of root issues requires considering other factors and examining roots directly. Read More
Root Rot
Root rot in cannabis is caused by pathogens in hydroponic systems or waterlogged soil. Roots become slimy, brown, and unhealthy. Above-ground symptoms include curled, drooping leaves. Cannabis plant diagnosis of root rot involves checking root appearance directly. Read More
Slugs or Snails
Slugs and snails are less common cannabis pests but unwelcome. They chew on leaves, leaving bite marks and slime trails. Finding slime trails and leaf damage is a clear sign in cannabis plant diagnosis of slug or snail presence. Read More
Spider Mites
Spider mites are common cannabis pests, related to spiders. They cause small spots on cannabis leaves as they feed. Early cannabis plant diagnosis of spider mites is crucial to prevent widespread infestation. Look for fine webbing as infestations progress. Read More
Stink Bug
Stink bugs are cannabis pests that lay distinctive patches of white eggs on leaves. Identifying these egg patches and the bugs themselves is part of cannabis plant diagnosis for stink bug management. Read More
Sulfur Deficiency
Sulfur deficiency in cannabis is rare and causes overall chlorosis, or yellowing of leaves, typically starting from the back of the leaf. This yellowing pattern is indicative in cannabis plant diagnosis of sulfur nutrient issues. Read More
Thrips
Thrips are small, fast-moving cannabis pests in various forms. They damage cannabis leaves, leaving streaks and discoloration. Recognizing thrip damage and the insects themselves is important for cannabis plant diagnosis and pest control. Read More
Tobacco Mosaic Virus (TMV)
Tobacco Mosaic Virus (TMV) is a cannabis disease causing odd yellow markings, twisted growth, and splotchy leaves. These unique symptoms are used in cannabis plant diagnosis for TMV. Read More
Under-watering
Underwatering cannabis leads to wilting and drooping plants. Underwatered leaves become limp and lifeless, often feeling papery. Wilting and limp leaves are key indicators in cannabis plant diagnosis for underwatering issues. Read More
White Powdery Mildew
White powdery mildew (WPM) is a fungal cannabis disease that appears as white powdery patches on leaves and stems, resembling flour. Identifying these white patches is straightforward in cannabis plant diagnosis of WPM. Read More
Whiteflies
Whiteflies are small white flying cannabis pests, resembling tiny moths. They behave similarly to spider mites and can infest plants quickly. Seeing small white flies is a clear sign in cannabis plant diagnosis of whitefly infestation. Read More
Wind Burn
Wind burn in cannabis is caused by excessive airflow, often from fans. It results in curled or clawing leaves, usually in the direct path of the fan. Leaf curling in airflow paths helps in cannabis plant diagnosis of wind burn. Read More
Zinc Deficiency
Zinc deficiency in cannabis causes yellowing in younger, upper leaves, specifically between the veins. Leaf tips also discolor and die. Yellowing upper leaves with these vein patterns are key to cannabis plant diagnosis of zinc deficiency. Read More
Alternative: Quick Text Guide to Common Cannabis Plant Problems (Beta Version)
