Grower Glossary

136 terms

A

Aeroponics (Aero): A way to grow plants where the roots hang in the air and get sprayed with water mixed with nutrients. It's like a misting system for roots. Grows plants fast but needs careful attention.
Antagonism (Nutrient): When too much of one nutrient blocks the plant from absorbing another. For example, excess potassium can stop calcium and magnesium uptake. Think of it as nutrients competing with each other at the root.
Anthocyanin: Natural pigments that turn cannabis leaves and buds purple, blue, or red. Triggered by cooler nighttime temperatures or genetics. Purely cosmetic — doesn't affect potency, but some growers love the look.
Aphids: Tiny soft bugs (usually green or black) that gather on leaves and stems to drink plant juice. They leave behind a sticky substance and can spread diseases to your plant.
Autoflower (Auto): A type of cannabis plant that starts making buds on its own after a few weeks, no matter how much light it gets. Great for beginners because they're faster and more forgiving than regular plants.
Auxin: A natural plant hormone that controls growth direction. It concentrates in the main tip, telling the plant to grow tall instead of bushy. When you top a plant, you remove the auxin source and it branches out instead.

B

Bloom Booster: A supplement with extra phosphorus and potassium (PK) marketed for bigger flowers. Often overhyped — research shows cannabis needs less P than most labels suggest. Overuse can lock out zinc, iron, and other micronutrients.
Boron (B): A nutrient plants need in tiny amounts. It helps build strong cell walls and move sugars around. If missing, you'll see brown patches and weird-looking new growth.
Broad Mites: Super tiny bugs you can't see without a magnifying glass. They attack new leaves and make them look twisted, shiny, and wet. Very hard to spot but cause serious damage.
Bud: The flower of the cannabis plant - this is the part people harvest and use. Buds grow where branches meet the main stem and get covered in sticky crystals called trichomes.
Bud Rot (Botrytis): A mold that grows inside thick buds, turning them gray and mushy. Happens when it's too humid or there's not enough air movement. Can ruin an entire harvest if not caught early.

C

Calcium (Ca): A nutrient that helps build strong cell walls, like bones for your plant. Without enough, new leaves curl up and get brown spots. Common problem in filtered or soft water.
CalMag: A calcium and magnesium supplement — the most commonly recommended add-on in cannabis growing. Essential for soft water, RO water, and coco coir grows that lack these naturally. Overdoing it can lock out potassium.
Calyx: The actual flower part of the bud - small tear-drop shaped pods that stack together to form buds. This is where seeds would develop if the plant was pollinated.
Canopy: The top layer of your plant's leaves and branches - like the ceiling of a forest. Growers try to keep the canopy flat and even so all buds get the same amount of light.
Cannabinoids: Natural chemicals found in cannabis plants that affect your body and mind. THC and CBD are the most famous ones, but there are over 100 different cannabinoids.
Caterpillars: Baby moths or butterflies that eat leaves and sometimes burrow into buds. Look for missing chunks of leaves and tiny dark droppings that look like pepper.
Cation: A positively charged nutrient ion like K⁺, Ca²⁺, or Mg²⁺. Cations enter roots through shared channels, so they compete with each other — too much of one means less of another gets absorbed. This is why nutrient ratios matter.
CBD (Cannabidiol): A cannabinoid that doesn't get you high but may help with pain, anxiety, and inflammation. Some strains are bred to have high CBD and low THC for medical users.
CBG (Cannabigerol): Sometimes called the 'mother cannabinoid' because other cannabinoids are made from it. Found in small amounts in most strains but some are bred for higher CBG levels.
Chelate: A special chemical form that wraps around a micronutrient (usually iron) to keep it dissolved and plant-available. Chelated iron stays usable at higher pH where regular iron would precipitate and lock out.
Chlorine (Cl): A nutrient plants need in tiny amounts for photosynthesis. Deficiency is rare since tap water usually has enough. Too much chlorine from pool chemicals can harm plants.
Chlorophyll: The green pigment inside leaves that captures light energy for photosynthesis. When a plant can't make enough chlorophyll (from nutrient problems or stress), leaves turn yellow — that's called chlorosis.
Chlorosis: When leaves turn yellow because they can't make enough green chlorophyll. Usually means the plant is missing nutrients or the pH is off.
Clone: A cutting taken from a mother plant that grows into an exact genetic copy. Clones skip the seed stage and are guaranteed to be female with the same traits as the parent.
Coco Coir (Coco): A growing material made from coconut shell fibers. It's like a halfway point between soil and hydroponics - holds water well but needs you to add all the nutrients.
Cola: A cluster of buds that grow tightly together, usually at the top of the main stem or branches. The main cola at the very top is often the biggest and densest bud on the plant.
Compost Tea: A liquid brew made by steeping compost in aerated water for 24-48 hours. Packed with beneficial bacteria and fungi that boost root health and nutrient availability. Popular in organic growing.
Copper (Cu): A nutrient plants need in tiny amounts for photosynthesis. If missing, leaves turn dark with blue or purple tints. Rare but can happen with very high pH.
Curing: The process of slowly drying harvested buds in jars over several weeks. This improves the smell, taste, and smoothness. Skipping this step means harsh, hay-smelling buds.

D

Deep Water Culture (DWC): A hydroponic method where plant roots sit directly in nutrient water with air bubbles. Plants grow very fast but you need to watch pH and oxygen levels closely.
Deficiency: When a plant isn't getting enough of a nutrient it needs. Shows up as yellow leaves, spots, slow growth, or other symptoms depending on what's missing.
Defoliation: Removing some leaves from the plant to improve airflow and light penetration. Done carefully during veg and early flower. Too much can stress the plant.

E

EC (Electrical Conductivity): A way to measure how strong your nutrient mix is. Higher EC means more nutrients dissolved in the water. Helps you avoid overfeeding or underfeeding.
Entourage Effect: The idea that all the compounds in cannabis (cannabinoids, terpenes, etc.) work better together than alone. Why whole-plant products may feel different than pure THC.

F

Fan Leaves: The big iconic cannabis leaves with fingers (usually 5-9). They're the plant's solar panels, catching light for energy. Not very potent but can be used for extracts.
Feminized Seeds: Seeds bred to produce only female plants (which make buds). Regular seeds have a 50/50 chance of being male or female.
Flowering Stage (Flower): When the plant stops focusing on growing bigger and starts making buds. In regular plants, this happens when they get 12 hours of darkness. Autoflowers do it automatically.
Flush / Flushing: Running plain water through your growing medium to wash out built-up salts — the fix for nutrient problems like salt buildup or nutrient burn. Note: flushing right before harvest to 'improve taste' is a widely disproved myth; a proper cure is what smooths the smoke.
Foliar Feeding: Spraying nutrients directly on leaves instead of watering them in. Plants can absorb nutrients through their leaves for quick fixes, but don't rely on this alone.
Foxtailing: When buds grow spiky, elongated towers instead of filling out round. Can be genetic (normal for some strains) or stress-induced from heat or lights too close. Stress foxtailing usually means conditions need adjusting.
Fungus Gnats: Tiny black flies that hover around your plants. Their babies (larvae) live in wet soil and munch on roots. A sign you're probably watering too much.

G

Genotype: A plant's complete DNA blueprint — its full set of genetic instructions. Two plants with the same genotype can still look different (different phenotypes) depending on how they're grown. Seeds from the same mother have similar but not identical genotypes.
Germination: When a seed sprouts and starts growing. Usually done by placing seeds in a damp paper towel or directly in soil. Takes 1-7 days for the taproot to appear.
Growing Medium: Whatever your plant's roots grow in - soil, coco coir, clay pebbles, or just water (hydroponics). Each type has pros and cons for beginners.

H

Harvest: Cutting down your plant when the buds are ripe. Timing is important - too early means less potency, too late can make effects more sleepy. Watch the trichome colors.
Heat Stress: When it's too hot for your plant. Leaves curl upward like tacos, edges turn brown, and the plant looks droopy near the lights. Keep temps below 85°F (30°C).
Hermaphrodite (Herm): A plant that develops both male and female parts, usually due to stress. Can pollinate itself and other plants, causing seedy buds. Remove immediately if found.
HST (High Stress Training): Techniques that intentionally damage the plant to control its shape, like topping or super cropping. Stresses the plant but can increase yields.
Humidity: How much moisture is in the air. Seedlings like 65-70%, veg likes 50-60%, flowering likes 40-50%. Too high causes mold, too low stresses plants.
Hybrid: A cannabis variety bred from both indica and sativa parents. Most modern strains are hybrids, combining traits from both types. Can lean indica or sativa dominant.
Hydroponics (Hydro): Growing plants in water with dissolved nutrients instead of soil. Plants can grow faster and bigger, but there's less room for error since there's no soil to buffer mistakes.

I

Immobile Nutrients: Nutrients that stay put once the plant uses them - it can't move them to new growth. When these are low, problems show up in NEW leaves at the top. Includes calcium, iron, and others.
Indica: One of the main types of cannabis, traditionally from mountainous regions. Known for shorter, bushier plants and relaxing effects. Though modern science suggests effects depend more on chemical profile than indica/sativa labels.
Internode: The section of stem between two nodes (where leaves grow). Short internodes mean a compact, bushy plant. Long internodes (stretching) often mean the plant wants more light.
Interveinal Chlorosis: When the areas between leaf veins turn yellow but the veins stay green, creating a striped pattern. Common sign of magnesium, iron, or manganese deficiency.
Iron (Fe): A nutrient plants need to make chlorophyll (the green stuff). When missing, new leaves turn bright yellow but veins stay green. Usually happens when pH is too high.

L

Leaf Blade: The flat, green part of a leaf — the wide surface that catches light and does photosynthesis. The 'fingers' on a cannabis leaf are called leaflets, and each one is its own blade attached to the petiole.
Landrace: Original cannabis strains that developed naturally in specific regions over centuries, like Afghan, Thai, or Colombian. They're the ancestors of modern hybrid strains.
Late Flower: The final 2-3 weeks before harvest when buds fatten up and trichomes mature. Some yellowing of leaves is normal now as the plant focuses all energy on the buds.
Leaf Miners: Tiny larvae that tunnel between the top and bottom layers of leaves, leaving squiggly white trails. Damage is mostly cosmetic but heavy infestations weaken plants.
Leaf Septoria: A fungal disease that makes round yellow or brown spots with dark edges on lower leaves. Spreads in humid conditions. Remove affected leaves and improve airflow.
LED: A type of grow light that uses light-emitting diodes. Modern LEDs are energy efficient, run cool, and can grow great cannabis. Most popular choice for home growers today.
Light Burn: When leaves get damaged from being too close to grow lights. Looks like bleaching or yellowing on the tips closest to the light. Move lights up or dim them.
Light Cycle: How many hours of light vs darkness your plant gets each day. Vegetative stage typically uses 18 hours light / 6 dark. Flowering uses 12/12 for regular photoperiod plants.
Lockout: When nutrients are in the soil but the plant can't absorb them, usually because the pH is wrong. Looks like deficiency even though you're feeding properly. Fix the pH first.
LST (Low Stress Training): Gently bending and tying down branches to create an even canopy. Doesn't stress the plant much but can significantly increase yields by exposing more bud sites to light.
Lux: A measurement of how bright light is to human eyes. While not perfect for plants, it's a free way to check light levels with a phone app. Cannabis likes 35,000-70,000 lux in flower.
Leaf Vein: The visible lines running through a leaf. Veins are the plumbing — they carry water, nutrients, and sugars between the leaf tissue and the rest of the plant. The thickest vein down the center is called the midrib.

M

Macronutrients: The main nutrients plants need in larger amounts: Nitrogen (N), Phosphorus (P), and Potassium (K) - that's what NPK on fertilizer labels means. Also calcium, magnesium, and sulfur.
Magnesium (Mg): A nutrient that's the central atom in chlorophyll - plants need it to be green and photosynthesize. When low, older leaves turn yellow between the veins but veins stay green.
Manganese (Mn): A micronutrient needed for photosynthesis. Deficiency causes pale, mottled new growth. Often confused with other deficiencies. Usually a pH problem.
Mealybugs: White fluffy-looking bugs that cluster where leaves meet stems. They suck plant sap and leave sticky honeydew. Wipe off with alcohol or use insecticidal soap.
Micronutrients: Nutrients plants need in tiny amounts: iron, manganese, zinc, boron, copper, molybdenum, and chlorine. Most fertilizers include these. Problems are usually pH-related.
Mobile Nutrients: Nutrients the plant can move from old leaves to new growth when running low. Deficiency shows in OLDER/lower leaves first. Includes nitrogen, phosphorus, potassium, and magnesium.
Molybdenum (Mo): A micronutrient needed in very tiny amounts for processing nitrogen. Deficiency is rare but causes older leaves to yellow and curl at the edges.
Mother Plant: A plant kept in vegetative stage specifically to take cuttings (clones) from. A good mother can provide unlimited identical copies of a favorite strain.
Mulder's Chart: A reference diagram showing how nutrients interact — which ones block each other (antagonism) and which ones help each other (synergy). Essential for understanding why adding more of a 'deficient' nutrient sometimes makes things worse.
Mycorrhizae: Beneficial fungi that attach to plant roots and massively extend the root network. They help absorb phosphorus and micronutrients in exchange for sugars from the plant. Common in organic soil growing but destroyed by heavy synthetic fertilizers.
Multiple Problems (Multi-Deficiency): When a plant shows symptoms of several deficiencies at once. Usually caused by a systemic issue like pH lockout, root damage, or salt buildup -- not multiple separate problems. Check pH and root health first.

N

Necrosis: When plant tissue dies and turns brown or black. This is the end stage of many problems - once tissue is dead, it won't recover. Focus on saving the healthy parts.
Nitrogen (N): The most important nutrient for leaf growth. Plants need lots during veg, less during flower. When low, lower leaves turn pale yellow and may fall off.
Nitrogen Toxicity: Too much nitrogen makes leaves dark green and shiny with tips that claw downward. Common mistake of new growers who overfeed. Flush with plain water.
Node: The joint on a stem where leaves, branches, or buds grow out. Counting nodes helps track plant maturity. More nodes generally means more potential bud sites.
NPK: The three numbers on fertilizer bottles showing Nitrogen-Phosphorus-Potassium ratios. For example, 10-5-5 is high nitrogen for veg growth; 5-10-10 is better for flowering.
Nutrient Burn: Damage from giving too much fertilizer. Leaf tips turn brown and crispy, then the damage spreads inward. Flush with plain water and feed at lower strength.

O

Overwatering: The #1 beginner mistake. Roots need oxygen, and too much water drowns them. Leaves droop but feel thick and heavy. Let soil dry out between waterings - lift the pot to check weight.

P

pH: A scale from 0-14 measuring how acidic or alkaline something is. Cannabis likes 6.3-6.8 in soil, 5.8-6.0 in coco, 5.5-6.0 in hydro. Wrong pH locks out nutrients even if they're present.
Petiole: The small stem that connects a leaf to the main branch. Think of it as the leaf's neck. Cannabis petioles are usually green but can turn red or purple under cold temperatures or certain deficiencies.
Phenotype (Pheno): The physical traits a plant shows - how it looks, smells, grows. Seeds from the same strain can have different phenotypes, like siblings looking different from each other.
Phosphorus (P): Essential for root growth, flowering, and energy transfer. Deficiency shows as dark leaves with purple stems, starting in lower leaves. Very important during flowering.
Photoperiod (Photo): Cannabis plants that need a change in light schedule to start flowering - specifically 12 hours of uninterrupted darkness. Most strains are photoperiod unless labeled autoflower.
Photosynthesis: The process where leaves use light energy to turn CO₂ and water into sugars (plant food). This is why light quality, intensity, and duration matter so much — more efficient photosynthesis means faster, healthier growth.
Pistils: The hair-like strands on female flowers, starting white and turning orange/brown as buds mature. They catch pollen for seed production. Lots of white pistils means the bud is still growing.
Potassium (K): Helps with water regulation, disease resistance, and bud development. Deficiency shows as brown, crispy leaf edges starting on older leaves. Important throughout the plant's life.
Powdery Mildew (PM): A fungus that looks like white powder sprinkled on leaves. Spreads fast in humid, stagnant air. Wipe leaves with diluted hydrogen peroxide and improve ventilation.
PPFD (Photosynthetic Photon Flux Density): A measure of how much usable light hits your plants per second — more accurate than lux for grow lights. Seedlings like 200-400, veg 400-600, flower 600-900+ µmol/m²/s. Most LED manufacturers list this spec.
PPM (Parts Per Million): Another way to measure nutrient strength in water, similar to EC. A PPM meter tells you how much stuff is dissolved in your water. Seedlings like 200-400ppm, flowering plants 800-1200ppm.
Pre-flower: Tiny structures that appear at nodes showing whether a plant is male or female. Females show white hairs (pistils), males show small ball-shaped pollen sacs.

R

Reservoir (Rezz): The tank that holds water and nutrients in a hydroponic setup. In DWC, the roots actually sit in the reservoir water. Growers monitor reservoir pH, EC, and temperature closely because changes affect plants within hours.
Re-vegetation (Revegging): When a flowering plant switches back to vegetative growth, usually from light leaks or intentional light schedule change. New growth looks weird with smooth, single-finger leaves.
Rhizosphere: The thin zone of soil right around the roots where beneficial bacteria and fungi live. Keeping this zone healthy with good moisture, oxygen, and organic matter helps the plant absorb nutrients more efficiently.
Root Bound: When roots completely fill a container and start circling. Growth slows and the plant may show deficiency symptoms. Time to transplant to a bigger pot.
Root Rot: When roots turn brown, slimy, and smelly from too much water or pathogens. Overwatered plants are most at risk. Can kill a plant if not caught early - let things dry out and add beneficial bacteria.
Runoff: The water that drains out the bottom of your pot after watering. Testing runoff pH and PPM tells you what's happening in the root zone. Aim for 10-20% runoff when feeding.
Russet Mites: Microscopic mites that cause yellowing and bronze coloring on upper growth. You need at least 60x magnification to see them. Often mistaken for nutrient deficiency.

S

Salt Buildup: When excess mineral nutrients accumulate in your growing medium over time. Happens from overfeeding or not enough runoff. Causes nutrient lockout and burnt leaf tips. Fix by flushing with 3x the pot volume of pH-adjusted water.
Sativa: One of the main cannabis types, traditionally from equatorial regions. Known for taller plants with narrow leaves and uplifting effects. Though effects depend more on chemical profile than sativa/indica labels.
SCROG (Screen of Green): A training technique using a net or screen to create a flat, even canopy. Branches are woven through the screen. Maximizes light exposure and can dramatically increase yields.
Seedling Stage: The first 2-3 weeks after a seed sprouts, when the plant is most delicate. Keep humidity high (65-70%), lights not too intense, and don't overwater or overfeed.
Senescence: Natural yellowing and leaf drop in the final weeks of flowering. The plant is redirecting all its energy to the buds. This is normal and not a problem to fix.
SOG (Sea of Green): A method of growing many small plants close together instead of fewer large ones. Each plant grows one main cola. Faster harvests but requires more plants.
Soil: The most forgiving growing medium for beginners. Good soil has nutrients built in, buffers pH swings, and is hard to overwater compared to hydro. Look for cannabis-specific soil or 'hot' soil.
Spider Mites: Tiny spider-like pests that leave small yellow dots on leaves and spin fine webs. They love hot, dry conditions and multiply fast. Check leaf undersides with a magnifier.
Stem: The main structural support of the plant, like its trunk. A thick, strong stem can support heavy buds. Some training techniques aim to strengthen the stem.
Stretch: The rapid vertical growth that happens in the first 2-3 weeks after switching to flowering. Plants can double or triple in height. Plan for this or your plants may hit the lights.
Substrate: The material your plant's roots grow in — soil, coco coir, perlite, rockwool, clay pebbles, or just water in hydroponics. Each substrate has different watering, feeding, and pH requirements.
Sugar Leaves: Small leaves that grow within the buds, often covered in trichomes (the 'sugar'). Usually trimmed off after harvest but great for making extracts or edibles.
Sulfur (S): A nutrient needed for proteins and enzymes. Deficiency makes new leaves turn lime green and feel papery. Not common if using decent fertilizer.
Symptom Location: WHERE problems appear helps identify them. Lower/older leaves = mobile nutrient issue (N, P, K, Mg). Upper/new leaves = immobile nutrient issue (Ca, Fe) or pH problem.
Synergy (Nutrient): When the presence of one nutrient helps the plant absorb or use another. For example, boron helps transport calcium, and phosphorus aids magnesium uptake. The opposite of antagonism — nutrients working together instead of competing.

T

THC (Tetrahydrocannabinol): The main compound in cannabis that produces the 'high.' Measured as a percentage of the bud's weight. Most strains range from 15-30% THC. Develops in trichomes.
Thrips: Tiny slender insects that scrape leaf surfaces, leaving silvery streaks and tiny black dots (their poop). They move quickly when disturbed. Use sticky traps and spinosad.
Topping: Cutting off the main growing tip to make the plant grow two main colas instead of one. Creates a bushier plant with more bud sites. Usually done during veg.
Toxicity: When there's too much of something, causing damage. Nutrient toxicity shows as burnt tips, dark leaves, or clawing. Different from deficiency (not enough).
Training: Techniques to control plant shape and increase yields. Includes LST (bending), topping (cutting), SCROG (screen), and more. Most plants benefit from some training.
Transpiration: When water evaporates from leaf surfaces, pulling more water and dissolved nutrients up from the roots — like the plant's circulatory system. Driven by temperature, humidity, and air movement. Low humidity speeds it up, high humidity slows it down.
Transplanting: Moving a plant to a bigger container. Do it before roots get too crowded. Water the day before, be gentle with roots, and don't bury the stem deeper than it was.
Trichomes: Tiny mushroom-shaped glands covering buds and sugar leaves - they look like frost or crystals. This is where THC, CBD, and terpenes are produced. Clear trichomes = not ready, milky = peak THC, amber = more sedating.
Trim: Removing excess leaves from harvested buds, either wet (right after cutting) or dry (after drying). Good trim improves appearance and smoke quality.

U

Underwatering: Not giving enough water. Leaves droop and feel thin, papery, and lifeless. The pot feels very light. Unlike overwatering, this is easily fixed - just water thoroughly.

V

VPD (Vapor Pressure Deficit): The relationship between temperature and humidity that affects how fast plants transpire. Advanced growers optimize VPD for faster growth. For beginners, just keep temp 70-85°F and humidity appropriate for the stage.
Vegetative Stage (Veg): The growth phase before flowering when the plant builds its structure - stems, branches, and leaves. Give lots of light (18+ hours), higher nitrogen, and let it get big before flipping to flower.

W

Whiteflies: Tiny white moth-like insects that fly up in clouds when you disturb the plant. They live under leaves and suck sap. Sticky traps and insecticidal soap work well.
Wind Burn: Damage from too much direct fan airflow. Leaves in the wind path get dry, curled edges and may look clawed. You want gentle air movement, not a hurricane.

Z

Zinc (Zn): A micronutrient needed for growth hormones and enzymes. Deficiency makes new leaves small, wrinkled, and twisted. Usually a pH problem rather than actually missing zinc.

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