Grower Glossary – FUpdated 8 days ago

F

The Grower Glossary – F covers everything from foliar sprays to flower development, fungi, and flushing. Learn how “F” terms define plant health, nutrient balance, and the art of finishing strong.

F1 Hybrid

A first-generation cross between two distinct parent strains, combining their strongest genetic traits.

Grower Slang: “First-gen cross” or “hybrid vigor.”

F1s are known for explosive growth, disease resistance, and consistency.

F2, F3 (Generational Breeding)

Subsequent generations of crosses made from F1 offspring.

Grower Slang: “Stabilizing the line.”

Used in cannabis breeding to lock in desirable phenotypes.

Fade (Nutrient Fade)

When leaves naturally yellow near harvest as the plant consumes stored nutrients.

Grower Slang: “Fall colors,” “flush fade.”

A healthy fade signals a clean, properly timed finish.

Fan Leaves

Large, broad leaves that power photosynthesis during veg.

Grower Slang: “Fans,” “solar panels.”

Remove selectively during defoliation for better light penetration.

Feeding Schedule

A structured plan outlining when and how much to feed your plants.

Grower Slang: “Feed chart,” “nutrient plan.”

Cronk Tip: Follow the Classic Line 3-Part Schedule or Bonnie & Clyde Auto Chart for consistent growth and balanced EC.

Feed Chart

A nutrient guide that breaks down ratios and dosages per stage (seedling, veg, bloom).

Grower Slang: “Feed plan.”

Always start at ¾ strength and adjust based on plant response.

Feed Hot

Applying a nutrient mix that’s too strong, resulting in leaf tip burn or stress.

Grower Slang: “Hot mix,” “burned the girls.”

Cronk Tip: Check EC before every feed; don’t exceed 2.2 in bloom.

Feed Light

A mild nutrient strength used for seedlings or sensitive strains.

Grower Slang: “Soft feed.”

Fertigation

The delivery of nutrients through irrigation water.

Grower Slang: “Feed-to-waste” or “drip feed.”

Common in coco and hydro grows for precision feeding.

Fertilizer

A substance providing essential nutrients to plants for growth and reproduction.

Grower Slang: “Nutes” or “juice.”

Cronk Tip: Use complete nutrient systems rather than single-element additives to prevent imbalance.

Fiber Pots

Fabric grow containers that promote airflow and root pruning.

Grower Slang: “Fabric pots,” “air pots.”

Improve root oxygenation and reduce overwatering.

FIM (F*** I Missed)

A high-stress pruning technique where the top growth tip is partially cut rather than fully topped.

Grower Slang: “FIM cut,” “multi-top.”

Produces 3–5 new tops from one cut. Great for maximizing canopy yield.

Fimmed (Plant State)

Describes a plant that has undergone FIM pruning.

Grower Slang: “Fimmed out.”

Finishing Stage

The final 1–2 weeks before harvest when plants ripen and trichomes mature.

Grower Slang: “Finishing,” “final push.”

Cronk Tip: Drop EC slightly and let the plant fade naturally.

Fire (Slang)

Grower slang for high-quality, potent, visually appealing cannabis.

Grower Slang: “That’s fire,” “straight gas.”

Represents strong genetics, good feeding, and perfect curing.

Fish Emulsion

An organic fertilizer made from decomposed fish, rich in nitrogen and trace minerals.

Grower Slang: “Fish juice.”

Cronk Tip: Best used during veg or early flower in soil grows.

Flavonoids

Plant compounds responsible for pigmentation and some aroma. They work alongside terpenes to influence color and flavor.

Grower Slang: “Flavor molecules.”

Float Valve

A hydroponic or irrigation control device that maintains water levels automatically.

Grower Slang: “Auto top-off.”

Flood and Drain (Ebb and Flow)

A hydro system that periodically floods and drains the root zone.

Grower Slang: “Ebb tray” or “flood table.”

Ensures roots receive nutrients and oxygen in cycles.

Flop (Bud Flop)

When heavy buds bend or fall due to weight or weak stems.

Grower Slang: “Flopping,” “bud flop.”

Cronk Tip: Use Armadillo Armour for silica support and trellising to prevent flops.

Flora (Microflora)

The collection of beneficial microbes in soil or root zones.

Grower Slang: “Soil life,” “micro community.”

Flower (Bloom)

The reproductive stage where cannabis forms resinous buds.

Grower Slang: “In flower,” “blooming.”

Triggered by a 12/12 light cycle or by age in autoflowers.

Cronk Combo: Clyde + Bud Booster + Sticky Bandit for optimal bloom performance.

Flower Cluster

A tight group of calyxes forming a bud.

Grower Slang: “Bud site,” “stack.”

Flower Initiation

The early stage of bloom where plants transition from vegetative growth to flowering.

Grower Slang: “Flip phase.”

Occurs within 10–14 days of switching to 12/12 lighting.

Flowering Time

The total duration a plant spends in bloom until harvest.

Grower Slang: “Run time.”

Autos: 6–10 weeks; Photoperiods: 8–12 weeks.

Flushing

Running plain, pH-balanced water through the medium to remove excess salts and buildup.

Grower Slang: “Flush run,” “clean out.”

Cronk Tip: Flush between stages or at finish to reset EC and improve final flavor.

Foliar Feeding

Applying nutrients or supplements directly to leaves via spray.

Grower Slang: “Leaf feed,” “foliar spray.”

Best done under low light conditions to prevent burn.

Foliar Burn

Damage caused by applying sprays in strong light or with too-hot concentrations.

Grower Slang: “Leaf burn.”

Always spray under low light or early in the day cycle.

Footprint (Lighting)

The coverage area of a grow light.

Grower Slang: “Light zone.”

Cronk Tip: Match fixture footprint to your canopy width for even light.

Force Flowering

Manually inducing bloom by shortening light hours or using light deprivation techniques.

Grower Slang: “Flipping early.”

Useful for outdoor growers controlling harvest timing.

FPH (Feed per Hour)

Measurement in automated irrigation setups showing how much nutrient solution is delivered each hour.

Grower Slang: “Drip rate.”

Frame (Plant Frame)

The structural shape of a plant — its main branches and canopy layout.

Grower Slang: “Structure.”

Training early builds a strong, balanced frame.

Frost / Frosty

A term describing heavy trichome coverage on buds and leaves.

Grower Slang: “Frosty,” “iced out,” “sugar-coated.”

Indicates high resin production and potency.

Full Spectrum Light

Lighting that mimics the entire natural light range from UV to infrared.

Grower Slang: “Sun-like spectrum,” “full spec.”

Modern LEDs provide full-spectrum light for both veg and bloom.

Fungicide

A product used to prevent or eliminate fungal infections like powdery mildew or bud rot.

Grower Slang: “Anti-mold spray.”

Always choose organic or OMRI-listed options for consumable crops.

Fungus Gnat

A small fly whose larvae feed on roots and decaying matter in moist soil.

Grower Slang: “Gnats.”

Cronk Tip: Allow dry-backs between feeds and use Diatomaceous Earth to control larvae.

Functional Leaf

A healthy, active leaf that contributes to photosynthesis and plant metabolism.

Grower Slang: “Active fan.”

Fulvic Acid

A natural compound derived from humic substances that enhances nutrient uptake and chelation.

Grower Slang: “Fulvics.”

Cronk Tip: Found in PuurOrganics for improved absorption and soil vitality.

Fungal Network (Mycorrhizae)

A network of beneficial fungi that link plant roots, sharing nutrients and communication signals.

Grower Slang: “Root web” or “myco net.”

Boosted by microbial inoculants like Monkey Juice.

Fusarium

A soil-borne fungal disease causing wilting, root rot, and vascular blockage.

Grower Slang: “Fusarium wilt.”

Prevent with good airflow, microbial diversity, and sterile practices.

Fuzzy Roots

Healthy white root tips often seen in hydro and coco grows — a sign of oxygenation and microbial health.

Grower Slang: “Happy roots.”

Fan Speed Controller

A device used to regulate the speed of exhaust or intake fans.

Grower Slang: “Fan dial.”

Helps stabilize temperature and humidity swings.

Flavor (Terpene Expression)

The taste profile of dried cannabis influenced by terpenes and nutrient balance.

Grower Slang: “Terp game,” “flavor chase.”

Proper feeding and curing preserve full flavor and aroma.

Flush Valve

A valve used in hydro systems to drain reservoirs or reset nutrient solutions quickly.

Grower Slang: “Drain tap.”

Flushing Agent

A solution that helps remove built-up salts from the medium faster than plain water.

Grower Slang: “Clearing solution.”

Optional during final flushes for smoother smoke.

Free Nitrogen (N₂)

Nitrogen gas in the atmosphere that must be fixed by bacteria before plants can use it.

Grower Slang: “Locked nitrogen.”

Inoculate soil with nitrogen-fixing microbes for better availability.

Frost Point

The temperature at which water vapor condenses or freezes — important for climate control in drying rooms.

Grower Slang: “Dew point.”

From foliar feeding to final flush, “F” is about fine-tuning. Use Sticky Bandit and Bud Booster during flower to push terpene and trichome potential to the limit.