Plant Doctor – Diagnose Your Plants!

Updated Jul 19, 2019

Use our cannabis growing problem pictures and interactive plant doctor tool to quickly diagnose your sick marijuana plants! Click the pictures below to learn about a marijuana problem, deficiency or symptom & get the solution! Still having trouble? Consult our 7-Step Remedy to 99% of Cannabis Growing Problems​​

An accidental revegging of cannabis causes unusual new growth and smooth leaf edges

Accidental Re-Vegging

"Re-veg" is short for "re-vegetation" and refers to what happens if a flowering plant stops flowering and re-enters the vegetative ...
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Cannabis plants with aphids have pale or dark bugs under the leaves, typically with white specks (baby aphids and their exoskeletons)

Aphids (also Greenflies & Blackflies)

Aphids are soft-bodied insects which can appear white, green, yellow, black, brown and red, depending on their stage of life and ...
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Barnacle scale insects look like unmoving growths on your cannabis stems and leaves

Barnacle Scales

These unusual bugs hang out on your stems and under your leaves without moving. Scale insects suck the life out ...
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A cannabis boron deficiency causes brown patches on leaves and causes thick, twisted or abnormal new growth.

Boron Deficiency

A boron deficiency in cannabis is relatively rare unless a plant is underwatered or in a really dry environment, and ...
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When broad mites attack cannabis they cause droop or twisted new growth, especially near the top of the plant, along with blistered and glossy looking leaves

Broad Mites

Broad mites on your cannabis plants are so tiny they are practically impossible to spot with the naked eye, and can ...
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Bud Rot on cannabis causes dying leaves to appear on the buds, and upon investigation you'll be able to see mold at the base of the leaves

Bud Rot or Mold

Bud rot in cannabis plants is caused by mold, and is most likely to appear when buds are dense and the ...
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A calcium deficiency in cannabis causes brown spots on the leaves

Calcium Deficiency

Calcium is an important nutrient which helps provide structure to the cannabis plant and helps it withstand stress like from ...
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Caterpillars and inch worms can leave holes in your cannabis leaves

Caterpillars & Inchworms

Sometimes the first sign of caterpillars / worms / cabbage loopers is just seeing chunks of your leaves missing. You may also see ...
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Example of a copper deficiency on a cannabis plant. The leaves turn dark, almost shiny looking, and edges and tips of leaves turn yellow

Copper Deficiency

A cannabis copper deficiency appears with leaf symptoms such as dark leaves that take on blue or even purple undertones. The ...
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Crickets don't infest cannabis often, but they can chew small holes in your leaves, and mole crickets can tunnel under your plants

Crickets

Crickets will happily eat your cannabis plants and leave small holes in your leaves. Mole crickets may be found digging around ...
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Fungus gnats looks like tiny flies buzzing around the soil, and are typically triggered by wet soil conditions

Fungus Gnats

A fungus gnat is so small it's thinner than the width of a quarter. They commonly appear when cannabis plants ...
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Example of grasshopper damage on a cannabis leaf

Grasshoppers

Grasshoppers (and sometimes locusts, which are basically just grasshoppers with wings) will happily eat your cannabis leaves, leaving holes, and live ...
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Heat stress causes cannabis leaves to start cupping (turn into "canoes"). Another symptoms is leaves pointing up

Heat Stress

Your cannabis plant can only withstand a certain amount of heat and light. After a certain point, your cannabis will ...
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Hemp russet mites on cannabis symptoms (yellow mass of bugs, tops of plants droop)

Hemp Russet Mites

Hemp russet mites are tiny bugs that attack cannabis plants. In fact, they are so small you can only see ...
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A cannabis iron deficiency causes the top and inner leaves to turn yellow or white

Iron Deficiency

A cannabis iron deficiency is usually seen first on bright yellow new leaves, and the symptoms of a cannabis iron deficiency ...
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Cannabis leaf damage from a leaf miner looks like a pale trail on the leaf

Leaf Miners

The term "leaf miner" is a common name for a type of pest actually lives inside the tissue of the leaf. These ...
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Leaf septoria on cannabis plants causes round yellow or brown spots on leaves

Leaf Septoria / Yellow Leaf Spot

Sometimes called "yellow leaf spot" or "leaf septoria," this condition is caused by a fungus (or sometimes a bacteria) that attacks ...
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Leafhopper damage on a cannabis leaf (appears as brown spots in clusters)

Leafhoppers

These pests will happily munch on your leaves, leaving brown or yellow spots. They can sometimes spread certain plant diseases ...
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Light burn or light stress on cannabis plants causes the leaves or tips of leaves to turn yellow. The worst symptoms are usually closest to the grow light.

Light Burn

Your cannabis plant can only withstand a certain amount of light. After a certain point, your cannabis will start turning ...
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The lower and older leaves start turning yellow between the veins when a cannabis plant gets a magnesium deficiency

Magnesium Deficiency

A light green or yellow coloring will begin to show on the veins and edges of the lower & older ...
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Male plants, hermies and bananas are not good. The first sign is "bananas" or "balls" where buds should be

Male Plants, Hermies & Bananas

Did you know there are “male” and “female” cannabis plants? Yes, cannabis plants are “dioecious” plants, which means each plant shows ...
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Manganese deficiency symptoms on a cannabis plant

Manganese Deficiency

Leaves may become yellow in between the veins, with mottled brown spots on the affected leaves. These brown dead patches ...
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These mealybugs look like white hairy bugs on your cannabis, leaving white patches that look like mold or webbing

Mealybugs

These white and hairy bugs enjoy warm temperatures and don't tolerate the cold. They have even been known to grow and spread ...
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A cannabis molybdenum deficiency causes red or pink coloring on the leaves

Molybdenum Deficiency

he initial symptoms may appear similar to a nitrogen deficiency (yellowing of older, lower leaves). Leaves may become mottled or ...
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Example of a nitrogen deficiency (the lower cannabis leaves turn yellow and fall off)

Nitrogen Deficiency

A cannabis nitrogen deficiency will cause the older, lower leaves on your plant to turn yellow, wilt away and eventually ...
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Example of a cannabis plant with a nitrogen toxicity (dark green leaves with the tips turned down)

Nitrogen Toxicity

Dark green leaves, shiny leaves, clawing, weak stems, and overall slow growth. Marijuana leaves that are nitrogen toxic often get ...
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Burnt leaf tips as the results of cannabis nutrient burn

Nutrient Burn

Nutrient burn or fertilizer burn is one of the most common beginner cannabis growing problems. The yellow or brown leaf ...
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Signs of an over-watered cannabis plant includes droopiness and wilting

Over-Watering

After watering, your plants start drooping. Usually the droopy leaves will feel firm and appear curled down (the whole leaf ...
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PH fluctuations can cause brown spots on middle or lower leaves

pH Fluctuations

Managing pH is crucial for cannabis plants to be able to take up nutrients through their roots. When the pH ...
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Example of a phosphorus deficiency on a cannabis plant (leaves get dark splotches and eventually drop)

Phosphorus Deficiency

A cannabis phosphorus deficiency generally appears on leaves from the lower/older parts of the plant. The lower leaves may turn ...
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Planthoppers

Planthoppers

by Nebula Haze Planthoppers can attack and infest cannabis, leaving a unique cotton-like growth while they suck the life out ...
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A potassium deficiency in cannabis causes burnt leaf tips and edges, as well as yellowing between the margins

Potassium Deficiency

With a marijuana potassium deficiency, you'll generally see symptoms on older leaves, but not always. Sometimes you'll see the symptoms at the ...
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Root problems in cannabis can cause a variety of symptoms, which can look like almost anything

Root Problems

Cannabis plants with root problems show many symptoms. They may appear overwatered or droopy, leaves curl or cup, wilted, slow ...
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Root Rot

Root Rot

Slimy, brown, twisted or unhealthy roots are caused by unwanted pathogens in your hydroponic tank! Curled, drooping, unhealthy leaves are ...
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Slugs and snail damage on cannabis leaves looks like a bunch of bites were taken out of the leaf (which is what happened) often accompanied by a trail of slime

Slugs or Snails

Although not the most common cannabis pest, slugs and snails are unwelcome visitors when they do show up! Sure signs ...
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Spider mites on cannabis cause spots on the leaves. You'll also start to see webbing and tiny bugs if you look closely

Spider Mites

Spider mites are part of the mite family and are related to spiders, ticks, and other mites. Although they’re a ...
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Young stink bugs massing on eggs that were laid on cannabis leaves

Stink Bug

Various species of stink bug have been known to attack cannabis plants. They lay distinctive patches of white eggs, which ...
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A sulphur deficiency in cannabis plants causes leaves to turn yellow (starting from the back of the leaf)

Sulfur Deficiency

A sulfur deficiency is relatively rare and will manifest itself as all-over chlorosis (yellowing of leaves), usually starting with the ...
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Thrip damage on cannabis leaves

Thrips

Thrips are small, fast-moving insects and can come in many forms, from pale wormy looking things to dark or golden ...
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Tobacco mosaic virus gives cannabis plants odd yellow markings and twisted growth

Tobacco Mosaic Virus (TMV)

Tobacco Mosaic Virus (TMV) is a virus that is commonly found in tobacco plants which causes splotchy or twisted leaves, strange mottling ...
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Under watered cannabis plants wilt or droop, and the leaves become limp and lifeless

Under-watering

If your plant is drooping, then it’s usually a sign of either over or under-watering. Leaves often seem “papery” and ...
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WPM causes white powdery patches on leaves or stems that may resemble flour

White Powdery Mildew

White powdery mildew is usually a minor annoyance that's easily fixed, but if you don't catch it early, white powdery ...
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Whiteflies

Whiteflies

White flies look like tiny white moths when they're flying around and otherwise behave a bit like spider mites; hanging ...
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Wind burn causes curled or clawing leaves in the direct flow from a fan

Wind Burn

Most indoor cannabis growers use fans to blow air around within the grow area. This creates a nice breezy environment that ...
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Zinc deficiency on cannabis plants cause the top leaves to turn yellow

Zinc Deficiency

With a cannabis zinc deficiency, younger leaves start yellowing in between the veins. Leaf tips get discolored and start dying ...
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