A

Absorb : To draw or take in. Rootlets absorb water and nutrients.

Alternating Current (AC): An electric current that reverses its direction at regularly occurring intervals. Homes have AC.

Acid: A sour substance, an acid or sour soil has a low pH, below 6.

Adobe: Heavy clay soil not suitable for container gardening.

Aeration: Supplying soil and roots with air or oxygen.

Aeroponics: Growing plants without soil by misting roots suspended in air.

Aggregate: Medium, usually gravel, that is about the same size and used for the inert hydroponic medium.

Alkaline: Refers to soil with a high pH. Any pH over 7 is considered alkaline.

All-purpose (General-purpose) fertilizer: A balanced blend of N-P-K. All-purpose fertilizer is used by most growers in the vegetative growth stage. Many All-purpose fertilizers also contain secondary and trace elements.

Amendment: Substance used to change soil texture. Amendments can be organic or mineral.

Ampere (amp): The unit used to measure the strength of an electric current. A 20-amp circuit is overloaded when drawing more than 17 amps.

Annual: A plant that normally completes its entire life cycle in one year or less, marijuana, marigolds and tomatoes are examples of plants grown as annuals.

Arc: Luminous discharge of electricity (light) between two electrodes.

Arc tube: A quartz container for luminous gases also houses the arc in HID lights.

Auxin: Classification of plant hormones. Auxins are responsible for foliage and root elongation.

Bacteria : Very small, one-celled organisms that have no chlorophyll. There are both beneficial and problem bacteria.

Beneficial insect : A good insect that eats bad flower and vegetable-munching insects.

Biodegradable : Able to decompose or break down through natural bacterial action, substances made of organic matter are biodegradable.

Biosynthesis : The production of a chemical compound by a plant

Bleach : Ordinary laundry bleach is used in a mild water solution as a soil fungicide.

Blood meal : High nitrogen organic fertilizer, made from dried blood. Dogs love blood meal

Bloom : To yield flowers

Blossom booster : Fertilizer high in phosphorus that increases flower yield.

Bolt : Term used to describe a plant that has gone to seed prematurely.

Bonsai : A very short or dwarfed plant.

Breaker box : Electrical circuit box having on/off switches rather than fuses.

Breathe : Roots draw in or breathe oxygen, stomata draw in or breathe carbon dioxide.

Bud : A small stem on a branch containing thick rows of calyxes.

Bud blight : A withering condition that attacks flower buds.

Buffering : The ability of a substance to reduce shock and cushion against pH fluctuations. Many fertilizers contain buffering agents.

Bulb : (1) The outer glass envelope or jacket that protects the arc tube of an HID lamp and blocks UV light, (2) Clove or bulb of garlic.

Bulbous trichome : A spherical-shaped resin producing plant hair with no stalk

C

Calyx : The pod harboring female ovule and two protruding pistils, seed pod.

Cannabinoid : A hydrocarbon unique to cannabis

Cannabis : Scientific name specifying genus for “hemp” affectionately known as “rope” and “marijuana” AKA dope.

Capitate stalked trichome : Resin-producing plant gland high in THC content

Carbon dioxide (CO2) : A colorless, odorless, tasteless gas in the air necessary for plant life. Cannabis can process up to 1500 ppm (parts per million) of CO2 but there is only 350 ppm that naturally occurs in the air.

Carbohydrate : Neutral compound of carbon, hydrogen and oxygen. Sugar, starch and cellulose are carbohydrates.

Caustic : Capable of destroying, killing or eating away by chemical activity

CBN : Cannabinol

Cell : The base structural unit that plants are made of, cells contain a nucleus, membrane and chloroplasts.

Cellulose : A complex carbohydrate that stiffens a plant. Tough stems contain stiff cellulose

Centigrade : A scale for measuring temperature where 100 is the boiling point of water and 0 is the freezing point of water.

CFM : Cubic feet per minute.

Chelates : Nutrients that are combined in an atomic ring so that they are easy for plants to absorb. Chelated nutrients are the most available forms of nutrients.

Chlorophyll : The green photosynthetic matter of plants. Chlorophyll is found in the chloroplasts of a green plant cell.

Chlorine : Chemical used to purify water.

Chloroplast : Containing chlorophyll.

Chlorosis : The condition of a sick plant with yellowing leaves due to inadequate formation of chlorophyll. Chlorosis is caused by a nutrient deficiency.

Circuit : A circular route traveled by electricity.

Clay : Soil made of very fine organic and mineral particles, clay is not suitable for container gardening.

Climate: The average condition of the weather in a garden room or outdoors.

Cola : Spanish and American slang word for a marijuana flower top.

Cold : Temperatures below 50 F

Color spectrum : The band of colors (measured in nanometers (nm)) emitted by a light source.

Color tracer : A coloring agent that is added to many commercial fertilizers, so the horticulturist knows there is fertilizer in the solution. Peters fertilizer has a blue color tracer.

Compaction : Soil condition that results from tightly packed soil. Compacted soil allows for only marginal aeration and root penetration.

Companion planting : Planting garlic, marigolds, etc., along with other plants to discourage insect infestations. Companion planting can be beneficial over a long term.

Compost : A mixture of decayed organic matter high in nutrients. Compost must be at least one year old. When compost is too young decomposition uses nitrogen. Once left to compost for a few months compost releases nitrogen.

Core : The transformer in the ballast is referred to as a core in HID lighting systems.

Cotyledon : Seed leaves, first leaves that appear on a plant.

Cross-pollinate : Pollinate two plants having different ancestry.

Crystal : (1) Appearance resin has when found on foliage. (2) Fertilizers many times come in soluble crystals.

Cubic foot : volume measurement in feet: Width times length times height equals cubic feet.

Cure : (1) Slow-drying process that makes marijuana more pleasant and palatable to smoke. (2) To make a sick plant healthy.

Cutting : (1) Growing tip cut from a parent plant for asexual propagation (2) Cutting
 

D

Damping-off : Fungus disease that attacks young seedlings and cuttings causing stem to rot at base. Over-watering is the main cause of damping-off.

Decompose : To rot or decay etc., through organic chemical change.

Dehumidify : To remove the moisture from air.

Dehydrate : To remove water from foliage.

Deplete : Exhaust soil of nutrients, making it infertile: Once a soil is used it is depleted

Desiccate : Cause to dry up. Safer’s Insecticidal Soap desiccates its victims.

Detergent : Liquid soap concentrate used as a: (1) wetting agent for sprays and water (2) pesticide. Note: Detergent must be totally organic to be safe for plants.

Dioecious : Having distinct male and female flowers.

Direct Current (DC) : An electric current that flows in only one direction.

Disease : Sickness of any kind.

Dome : The part of the HID outer bulb opposite the neck and threads.

Dome support : The spring-like brackets that mount the arc tube within the outer envelope.

Dose : Amount of fertilizer, insecticide, etc., given to a plant, usually in water solution.

Drainage : Way to empty soil of excess water: with good drainage. Water passes through soil evenly, promoting plant growth. With bad drainage water stands in soil, drowning roots.

Dripline : A line around a plant directly under its outermost branch tips. Roots seldom grow beyond the drip-line.

Drip system : A very efficient watering system that employs a main hose with small water emitters. Water is metered out of the emitters, one drop at a time.

Dry ice : A cold, white substance formed when carbon dioxide is compressed and cooled. Dry ice changes into CO2 gas at room temperatures.

Dry soil pocket : Small portion of soil that remains dry after watering: Dry soil pockets may be remedied by adding a wetting agent (soap) to water and/or waiting 15 minutes between waterings.

Dry well : Drain hole, filled with rocks.
 

E

Electrode : A conductor used to establish electrical arc or contact with non-metallic part of circuit.

Elongate : Grow in length.

Envelope : Outer protective bulb or jacket of a lamp.

Elongate : To grow in length. Cannabis Elongates from 3 to a foot when flowering is induced.

Emit : To give off, send out (light).

Encarsia Formosa : A parasitic wasp that preys on whiteflies Envelope - outer protective bulb or jacket of a lamp

Epsom salts : Hydrated, magnesium sulfate in the form of white crystalline salt: Epsom salts add magnesium to soil.

Equinox : The point at which the sun crosses the equator and day and night are each 12 hours long. The equinox occurs twice a year, in spring and fall.

Extension cord : Extra electrical cord that must be 14-gauge or larger (i.e. 12- or 10-gauge).
 

F

Feed : Fertilize.

Fan leaves : Large, fan-like marijuana leaves: Fan leaves are usually low in potency.

Female : Pistilate, ovule, seed producing.

Fertigate : To fertilize and irrigate at the same time.

Fertilizer burn : Over-fertilization. First leaf tips burn (turn brown) then leaves curl.

Fixture : Electrical fitting used to hold electric components.

Flat : Shallow (three-inch) deep container, often 18 by 24 or 10 x 20 inches with good drainage, used to start seedlings or cuttings.

Flat white : Very reflective, whitest white paint available. Magnesium or titanium white, semi-gloss is a favorite.

Fluorescent lamp : Electric lamp using a tube coated with fluorescent material, which has low lumen and heat output. A fluorescent lamp is excellent for rooting cuttings.

Foliage : The leaves or more generally, the green part of a plant.

Foliar feeding : Misting fertilizer solution which is absorbed by the foliage.

Fritted : Fused or embedded in glass or in semi-soluble material like calcium carbonate. Fritted trace elements (FTE) are long-lasting and do not leach out easily.

Fungicide : A product that destroys or inhibits fungus.

Fungistat : A product that inhibits fungus keeping it in check.

Fungus : A lower plant lacking chlorophyll which may attack green plants. Mold, rust, mildew and mushrooms are fungi.

Fuse : Electrical safety device consisting of a metal that MELTS and interrupts the circuit when circuit is overloaded.

Fuse box : Box containing fuses that control electric circuits.

 

G

GPM : Gallons per minute

General purpose fertilizer : See: ALL-PURPOSE FERTILIZER.

Gene : Part of a chromosome that influences the development of a plant. Genes are inherited through sexual propagation.

Genetic make-up : The genes inherited from parent plants. Genetic make-up is the most important factor dictating vigor.

Glandular trichome : Resin secreting plant hair.

Guano : Dung from birds, high in organic nutrients: Sea bird guano is noted for being high in nitrogen.

 

H

Halide: Binary compound of a (halogens) with an electropositive element(s).

Halogen : Any of the elements fluorine, chlorine, bromine, iodine and astatine existing in a free state. Halogens are in the arc tube of a halide lamp.

Hemp : Fibrous cannabis low in THC, used to make rope and give people who smoke it a headache.

Hermaphrodite : One plant having both male and female flowers. The breeding of hermaphrodite is hard to control.

Hertz (Hz) : A unit of a frequency that cycles one time each second. A home with a 60 hertz AC current cycles 60 times per second.

HID : High Intensity Discharge.

Honeydew : A sticky, honey-like substance secreted onto foliage by aphids, scale and mealy bugs.

Hood : Reflective cover of a HID lamp. A large, white HOOD is very reflective.

HOR : The abbreviation stamped on some HID bulbs meaning they may be burned in a horizontal position.

Horizontal : Parallel to the horizon, ground or floor.

Hormone : Chemical substance that controls the growth and development of a plant. Root-inducing hormones help cuttings root.

Horticulture : The science and art of growing plants.

Hose bib : Water outlet containing an on/off valve.

Hostile environment : Environment that is unfriendly and inhospitable to disease and conducive to plant growth.

Hot : Temperature over 90 F.

Humidity (relative) : Ratio between the amount of moisture in the air and the greatest amount of moisture the air could hold at the same temperature.

Humus : Dark, fertile, partially decomposed plant or animal matter. Humus forms the organic portion of the soil.

Hybrid : An offspring from two plants of different breeds, variety or genetic make-up.

Hydrated lime : Instantly soluble lime used to raise or sweeten soil.

Hydrogen : Light, colorless, odorless gas. Hydrogen combines with OXYGEN to form water.

Hydroponics : Growing plants in nutrient solutions without soil.

Hygrometer : Instrument for measuring relative humidity in the atmosphere. A hygrometer will save time, frustration and money.

 

I

Inbred : (True breed) offspring of plants of the same breed or ancestry.

Induce : To effect, cause or influence via stimulation. Flowering is induced via a 12-hour photoperiod.

Inert : Chemically non-reactive. Inert growing mediums make it easy to control the chemistry of the nutrient solution.

Insecticide : A product that kills or inhibits insects.

Intensity : The magnitude of light energy per unit. Intensity diminishes the farther away from the source. In short, light fades exponentially fast.

 

J

Jacket : Protective outer bulb or envelope of lamp.

Jiffy 7 pellet : Compressed peat moss wrapped in an expandable plastic casing. When moistened, a Jiffy 7 pellet expands into a small pot that is used to start seeds or cuttings.

 

K

Kilowatt-hour : Measure of electricity used per hour. A 1000-watt HID uses one kilowatt an one hour.

 

L

Lacewing : Beneficial insect that preys on aphids and other pest insects.

Leach : Dissolve or wash out soluble components of soil by heavy watering.

Leader : See MERISTEM.

Leaf curl : Leaf malformation due to over-watering, over fertilization, lack of magnesium, insect or fungus damage or negative tropism.

Leaflet : Small immature leaf.

Leggy : Abnormally tall, with sparse foliage. A leggy plant is usually caused by lack of light.

Life cycle : A series of growth stages through which plant must pass in its natural lifetime. The stages for an annual plant are seed, seedling, vegetative and floral.

Light mover : A device that moves a lamp back and forth or in a circle across the ceiling of a garden room to provide more even distribution of light.

Lime : Used in the form of DOLOMITE or HYDRATED LIME to raise and stabilize soil pH.

Litmus paper : Chemically sensitive paper used for testing pH.

Loam : Organic soil mixture of crumbly clay, silt and sand.

Lumen : Measurement of light output: One lumen is equal to the amount of light emitted by one candle that falls on one square foot of surface located one foot away from one candle.


 

M

Macro-nutrient : One or all of the primary nutrients N-P-K or the secondary nutrients magnesium and calcium.

Manicure : Trim leaves and large stems from buds with scissors or fine pruners

Marijuana : Cannabis with high cannabinoids profile. Illegal drug ingested for its THC content

Mean : Average throughout life. HIDs are rated in mean lumens.

Meristem : Tip of plant growth, branch tip.

Micro- nutrients : Also referred to as TRACE ELEMENTS, including S, Fe, Mn, B, Mo, Zn and Cu.

Millimeter : Thousandth of a meter approximately 04. inch.

Moisture meter : An electronic device that measures the exact moisture content of soil at any given point.

Monochromatic : Producing only one color. LP sodium lamps are monochromatic.

Mother Nature : The vast outdoors and all she holds: The indoor horticulturist assumes the role of Mother Nature.

Mother plant : Female marijuana plant that is used for cutting (cloning) stock. A mother plant maybe grown from seed or be a clone.

Mulch : A protective covering of organic compost, old leaves, etc. Indoors, mulch keeps soil too moist and possible fungus could result.

 

N

Nanometer : 0.000001 meter, nm is used as a scale to measure electromagnetic wave lengths of light, Color and light spectrums are expressed in nanometers (nm).

Necrosis : Localized death of a plant part.

Neck : Tubular glass end of the HID bulb, attached to the threads.

Nursery : Gardening store that sells many of the things indoor marijuana horticulturists need. A nursery is a great place to gather information.

Nutrient : Plant food, essential elements N-P-K, secondary and trace elements fundamental to plant life.

 

O

Ohm’s Power Law : A law that expresses the strength of an electric current. Volts times Amperes equals watts.

Optimum : (1) The most favorable condition for growth. (2) Peak production.

Organic : Made of, or derived from or related to living organisms. In agriculture organic means “natural”. In chemistry, organic means “a molecule or substance that contains carbon”.

Outbred : See hybrid.

Overload : Load to excess. A 20-amp circuit drawing 17 amps is overloaded.

Ovule : A plant’s egg found within the calyx, it contains all the female genes. When fertilized, an ovule will grow into a seed.

Oxygen : Tasteless, colorless element, necessary in soil to sustain plant life as well as animal life.

 

P

Parasite : Organism that lives on or in another host organism. Fungus is a parasite.

Passive : Hydroponic system that moves the nutrient solution passively through absorption or capillary action

Peat : Partially decomposed vegetation (usually moss) with slow decay due to extreme moisture and cold.

Perennial : A plant, such as a tree or shrub, that completes its life cycle over several years.

Perlite : (1) Sand or volcanic glass, expanded by heat, holds water and nutrients on its many irregular surfaces. (2) Mineral soil amendment.

pH : A scale from 1 to 14 that measures the acid-to-alkaline balance a growing medium (or anything). In general plants grow best in a range of 5.5 to 6.8 pH.

pH tester : Electronic instrument or chemical used to find where soil or water is on the pH scale.

Photometrics : The study of light, especially color.

Phosphor coating : Internal bulb coating that diffuses light and is responsible for various color outputs.

Photoperiod : The relationship between the length of light and dark in a 24-hour period.

Photosynthesis : The building of chemical compounds (carbohydrates) from light energy, water and carbon dioxide.

Phototropism : The specific movement of a plant part toward a light source.

Pigment : The substance in paint or anything that absorbs light, producing (reflecting) the same color as the pigment.

Pistils : Small pair of fuzzy white hairs extending from top of calyx. Pistils catch pollen and channel it into contact with the ovule for fertilization.

Pollen : (1) Fine, yellow, dust-like microspores containing male genes pollen sack. Male flower containing pollen. (2) Sieved glandular trichomes with a high THC content. Pollen, as it is known in Europe, is pressed into hashish.

Pod seed : A dry calyx containing a mature or maturing seed.

Pod, seed : A dry calyx containing a mature or maturing seed.

Pot-bound : Bound, stifled or inhibited from normal growth, by the confines of a container. Root system becomes pot-bound.

Potent : Marijuana rich in THC that provides a desirable psychoactive effect

Power surge : Interruption or change in intensity of electricity.

Predator : Beneficial insect or parasite that hunts down and devours harmful insects.

Primary nutrients : N-P-K.

Primo : American slang word for potent, top quality cannabis

Propagate : (1) Sexual: produce a seed by breeding different male and a female flowers (2) Asexual: to produce a plant by taking cuttings.

Prune : Alter the shape and growth pattern of a plant by cutting stems and shoots. A fruit that gives you diarrhea.

PVC pipe : Plastic (polyvinyl chloride) pipe that is easy to work with, readily available and used to pipe water into a garden room or make a watering wand.

Pyrethrum : Natural insecticide made from the blossoms of various chrysanthemums.

 

R

Rejuvenate : Restore youth. A mature plant, having completed its life cycle (flowering), may be stimulated by a new 18-hour photoperiod, to rejuvenate or produce new vegetative growth.

Resin glands : Tiny pores that secrete resin

Root-bound : See POT BOUND.

Root hormone : Root-inducing substance.

 

S

Salt : Crystalline compound that results from improper pH or toxic buildup of fertilizer. Salt will burn plants, preventing them from absorbing nutrients. Mineral salts-nutrients used to supply elements in hydroponic formulas.

Seal-a-meal : Airtight sealer for plastic baggies used to seal in freshness of pungent marijuana.

Sea of Green : Sea of Green (SOG) is the theory of harvesting lots of small plants, matured early to get the fastest production of buds available.

Secondary nutrients : Calcium (Ca) and magnesium (Mg).

Seed : The mature, fertilized, ovule of a pistilate plant, containing a protective shell, embryo and supply of food: A seed will germinate and grow, given heat and moisture.

Short circuit : Condition that results when wires cross and form a circuit. A short circuit will blow fuses.

Sinsemilla : Two Spanish words: sin = without, semilla = seed combined into one word by Americans: Sinsemilla describes flowering female cannabis, that has not been fertilized.

Soap : (1) Cleaning agent. (2) Wetting agent. (3) Insecticide. All soap used in horticulture, should be biodegradable.

Socket : Threaded, wired holder for a bulb.

Soilless mix : A growing medium, made up of mineral particles such as vermiculite, perlite, sand, pumice, etc. Organic moss is many times a component of soilless mix

Soluble : Able to be dissolved in water.

Solution : (1) Mixing a solid or liquid with water to form a Solution. (2) Answer to a problem.

Spore : Seed-like offspring of a fungus.

Sprout : (1) A recently germinated seed (2) Small new growth of leaf or stem.

Square feet (sq. ft.) : Length (in feet) times width equals square feet.

Stagnant : Motionless air or water. Water must be drained and not become stagnant for healthy marijuana growth.

Stamen : Male, pollen producing.

Starch : Complex carbohydrate. Starch is manufactured and stored food.

Sterilize : Make sterile (super-clean) by removing dirt, germs and bacteria.

Strain : (l) Ancestry, lineage, phenotype, a particular type of marijuana having the same characteristics. (2) To abuse a plant by withholding nutrients, water, etc.

Stroboscopic effect : A quick pulsating or flashing of a lamp.

Stress : A physical or chemical factor that causes extra exertion by plants. A stressed plant will not grow as well as a non-stressed plant.

Stomata : Small mouth-like or nose-like openings (pores) on leaf underside, responsible for transpiration and many other life functions. The millions of stomata must be kept very clean to function properly.

Sugar : Food product of a plant. Carbohydrates that contain hydrocarbon chain.

Super-bloom : A common name for fertilizer high in phosphorus that promotes flower formation and growth.

Synthesis : Production of a substance, such as chlorophyll, by uniting light energy and elements or chemical compounds.

Sump : Reservoir or receptacle that serves as a drain or holder for hydroponic nutrient solutions.

 

T

Taproot : The main or primary root that grows from the seed. Lateral roots will branch off the taproot.

Taxonomy : Cutting in order and giving a name.

Teflon tape : Tape that is extremely useful to help seal all kinds of pipe joints. I like Teflon tape better than putty.

Tepid: Warm 70 to 80 degrees F (21 to 27 degrees C). Always use tepid water around plants to facilitate chemical processes and ease shock.

Terminal bud: Bud at the growing end of the main stem.

THC : Tetrahydrocannibinol

Thermostat: A device for regulating temperature. A thermostat may control a heater, furnace or vent fan.

Timer: An electrical device for regulating photoperiod, fan, etc. A timer is a must in all grow rooms.

Thin: cull or weed out weak slow growing seedlings.

Toxic life : The amount of time a pesticide or fungicide remains active.

Transformer : A devise in the ballast that transforms electric power from one voltage to another.

Transpire : Give off water vapor and by-products via the stomata and carbon dioxide intake at the leaves.

Trellis: Frame of small boards (lattice) that trains or supports plants.

True breed : See INBRED.

Tungsten : A heavy, hard metal with a high melting point, which conducts electricity well. Tungsten is used for a filament in tungsten halogen and incandescent lamps.

 

U

Ultraviolet : Light with very short wave lengths, out of the visible spectrum, past the blue-violet.


 

V

Vacuole : space within a cell separate from the cytoplasm
  
Variety : Strain, phenotype (see strain).

Vent : Opening such as a window or door that allows the circulation of fresh air.

Ventilation : Circulation of fresh air, fundamental to healthy indoor garden. An exhaust fan creates excellent ventilation.

Vertical: Up and down perpendicular to the horizontal.

Vitamin B1 : Vitamin that is absorbed by tender root hairs, easing transplant wilt and shock.
 

W

Weed : (l) Slang word for marijuana in the U.S. (2) Any undesirable plant. One persons weed is another persons flower!

Wetting agent : Compound that reduces the droplet size and lowers the surface tension of the water, making it wetter. Liquid concentrate dish soap is a good wetting agent if it is biodegradable.

Whorled Phyllotaxy : three or more limbs appear per node

Wick : Part of a passive hydroponic system using a wick suspended in the nutrient solution, the nutrients pass up the wick and are absorbed by the medium and roots.

Wild : weedy, escaped, naturalized, or indigenous

X

Xylem : vascular tissue of the roots, stems, and leaves through which water and nutrients flow upward from the roots