The Grower's Glossary: Every Term You'll Meet, Decoded

LST, VPD, flushing, hermie, trichomes, DWC — the full dictionary of grow-speak so forums, videos, and our guides all make sense.

Grow culture speaks its own language. Here's the working dictionary — skim it once, then come back whenever a forum post reads like alphabet soup.

The plant itself

Cola — a main flowering bud site; the "top" every training method multiplies.
Node — where a branch/leaf meets the stem. Spacing between nodes signals light quality.
Fan leaves — the big solar panels. Sugar leaves — the small frosted leaves inside buds.
Calyx — the actual flower structure that stacks into buds. Pistils — the white hairs; they darken and curl as flower matures.
Trichomes — the resin glands (the "frost") holding cannabinoids and terpenes. Their color (clear → cloudy → amber) is the harvest clock.
Cotyledons — the first round seed leaves. They yellowing early is normal.
Taproot — the first root from a germinated seed. Snap it and the seed is done.

Photoperiod (photo) — flowers when darkness hits 12 h. Autoflower (auto) — flowers on an internal timer regardless of light schedule.
Feminized (fem) — bred to produce ~99 % female plants. Regular seeds — 50/50 male/female.
Cultivar / strain — a named genetic line. Pheno(type) — an individual expression of it; two seeds of one strain can grow differently.
Hermie (hermaphrodite) — a stressed female growing male pollen sacs; can seed a whole tent.
Landrace — an old, region-native strain. Clone/cut — a rooted cutting, genetically identical to its mother.

LST (low-stress training) — bending and tying branches flat to multiply tops without cutting.
Topping — snipping the main tip so two colas grow instead of one. FIM — a sloppier top that can give 3–4.
SCROG — a screen/net the canopy is woven through for a flat, even table. SOG — many small plants flipped early.
Defoliation — strategic leaf removal for light and airflow. Lollipopping — stripping the shaded bottom third so energy goes topside.
Mainlining/manifolding — structured topping into a symmetrical hub of equal colas.
Super cropping — deliberately crushing/bending a stem softly to reset height (high-stress).

VPD (vapor pressure deficit) — temp + humidity combined into one "how hard is the air pulling water from leaves" number.
RH — relative humidity. PPFD — light intensity actually hitting leaves. DLI — total light received per day.
Quantum board / bar light — modern LED formats. Blurple — old-style purple LEDs; usually a red flag.
Inline fan / carbon filter ("scrubber") — exhaust and smell control. Lung room — the room your tent breathes from.
Runoff — water that drains from the pot; its pH/EC hints at root-zone conditions.
EC / PPM — measurements of nutrient concentration in water.

Medium — what roots live in: soil, coco coir, rockwool, or water (hydro/DWC).
Living soil / no-till — soil built to feed plants through microbial life, often water-only.
Super soil — heavily amended soil "cooked" in advance (see the Soil Lab).
Amendments — dry organic inputs: worm castings, kelp, alfalfa, bone/fish/crab meal, guano, rock dusts.
Top-dress — sprinkling amendments on the soil surface mid-grow. Tea — aerated microbe/nutrient brew.
Cal-Mag — calcium+magnesium supplement; the usual fix for LED-era rusty spots.
N-P-K — nitrogen, phosphorus, potassium: the three numbers on every fertilizer.
Lockout — nutrients present but chemically unavailable (usually pH). Flush — plain-water reset of a salted-up medium.
Mycorrhizae (Mykos) — root-partner fungi that extend nutrient reach.

Flip — switching photos to 12/12 to start flower. The stretch — the height explosion in flower weeks 1–3.
Fade — the healthy late-flower yellowing as the plant spends its reserves.
Wet/dry trim — trimming at chop vs. after drying.
Cure — the slow jar-finish that turns "decent" into "excellent." Burp — opening jars briefly during cure.
62 % pack — two-way humidity packs for jars. Loupe — the magnifier for trichome checks.
Larf / popcorn — small airy under-canopy buds. Bud rot (botrytis) — mold inside dense colas; the late-flower nightmare.

Bookmark this one — every other guide on the site will read twice as fast.