Glossary - Growing
Alternating Current (AC) - an electric current that reverses
its direction at regularity occurring intervals. Homes have A.C.
Adobe - heavy clay soil, not suitable for container
gardening or hydroponics.
Aeration - supplying growing mediums and roots with air or
Aeroponic - growing plants by misting roots suspended in
air. No medium is needed with this method and usually only small plants that
need no support are grown this way.
Aggregate - medium usually grow rocks, gavel, or lava rocks
that is all nearly the same size, and used for an inert hydroponic medium.
Alkaline - refers to soil or hydroponic nutrient solution
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 for soil and is used by most growers in the
vegetative growth stage. Miracle-Gro and Peters is an example. They are not
recommended for hydroponics.
Ampere (amp) - the unit used to measure the strength of an
electric current; A 20-amp circuit is overloaded when drawing more than 17amps,
Annual - a plant that normally completes its entire life
cycle in one year or less: Marigolds and tomatoes are examples of annual
Arc - luminous discharge of electricity (light) between two
Arc tube - container for luminous gases; also houses the
Auxin - classification of plant hormones; Auxins are
responsible for foliage and root elongation.
Bacteria - very small, one-celled organisms that have no
Beneficial insect - a good insect that eats bad insects that
attack your plants.
Biodegradable - able to decompose or break down through
natural bacterial action; Substances made of organic matter are biodegradable.
Bleach - Ordinary laundry bleach is used in a 1 part bleach
to 10 parts water solution as a garden fungicide. Use this solution to clean
all your equipment between harvests to rid of any lingering contamination.
Bolt - term used to describe a plant that has run to seed
prematurely which means that it bloomed because of heat or other reasons.
Bonsai - a very short or dwarfed plant.
Breaker box - electrical circuit box having on/off switches
rather than fuses.
Breath - Roots draw in and breath oxygen, stomata draw in
and breathe CO2.
Bud blight - a withering condition that attacks flower buds.
Buffering - the ability of a substance to reduce shock and
cushion against pH fluctuations. Many soil fertilizers contain buffering agents
but it is much more critical to maintain the correct pH with hydroponics than
with soil growing..
Bulb - 1. the outer glass envelope or jacket that protects
the arc tube of an HID lamp 2. clove or bulb of garlic.
Calyx - the pod harboring female ovule and two protruding
pistils, seed pod.
Carbon dioxide (CO;) - a colorless, odorless, taste less gas
in the air necessary for plant life.
Carbohydrate - neutral compound of carbon, hydrogen and
oxygen; Sugar, starch and cellulose are carbohydrates.
Caustic - capable of destroying, killing or eating away by
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.
CFM - Cubic feel per minute.
Chelate - combining nutrients in an atomic ring that is easy
for plants to absorb.
Chlorophyll - the green photosynthetic matter of plants:
Chlorophyll is found in the chloroplasts of a cell.
Chlorine - chemical used lo 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, usually iron or imbalanced pH.
Circuit - a circular route traveled by electricity.
Clay - soil made of very tine organic and mineral particles:
Clay is not suitable for container gardening.
Climate - the average condition of the weather in a grow
room or outdoors.
Color spectrum - the band of colors (measured in 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 has a blue color tracer.
Compaction - soil condition that results from lightly 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.
Compost - a mixture of decayed organic matter, high in
nutrients; Compost must be at least one year old. When to young, decomposition
uses nitrogen; after sufficient decomposition, compost releases nitrogen.
Core - the transformer in the ballast is referred to as a
Cotyledon - seed leaves first leaves that appear on a plant.
Cross-pollinate - pollinate two plants having different
Cubic foot - volume measurement in feet: Width times length
times height equals cubic feet.
Cutting - 1. growing tip cut from a parent plant for asexual
propagation 2. clone
Damping-off - fungus disease that attacks young seedlings
and cuttings causing them to rot at the base: Over-watering is the main cause
Direct Current (DC) - an electric current that flows in only
Deplete - exhaust soil of nutrients, making in infertile:
Once a soil is used it is depleted.
Desiccate - cause to dry up. Safari'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.
Dome - the part of the HID outer bulb opposite the neck and
Dome support - the spring-like brackets that mount the arc
tube within the outer envelope.
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.
Drip line - a line around a plant directly under its
outermost blanch 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 CO2; is
compressed and cooled: Dry ice changes into CO2; gas at room temperatures. For
small garden rooms this my be an easy way to add CO2.
Dry well - drain hole, filled with rocks.
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.
Equinox - the point at which the sun crosses the equator and
day and night are each 12 hours long: The equinox happens twice a year.
Extension cord - extra electrical cord that must be 14-gauge
or larger (i.e. 12-or IO-gauge).
Feed - fertilize.
Female - pistillate, ovule, seed-producing.
Fertilizer burn - over-fertilization: First leaf tips bum
(turn brown) then leaves curl.
Fixture - electrical fitting used lo hold electric
Flat - shallow (three-inch) deep container, often 18 by 24
inches with good drainage, used to start seedlings or cuttings.
Flat white - very reflective, whitest white paint available.
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
Foliar feeding - misting fertilizer solution which is
absorbed by the foliage.
Fritted - fused or embedded in glass, 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 in check.
Fungus - a lower plant lacking chlorophyll which may attack
green plants; Mold, rust, mildew, mushrooms and bacteria 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
GPM - Gallons per minute.
General purpose fertilizer - See ALL-PURPOSE FERTILIZER.
Gene - part of a chromosome that influences the development
and potency 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 and potency.
Halide - binary compound of a halogen(s) with an
Halogen - any of the elements fluorine, chlorine, bromine,
iodine and astatine existing in a free state: Halogens arc in the arc tube of a
Hermaphrodite - one plant having both male and female
flowers: The breeding of hermaphrodites 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, while 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.
Hose bib - water outlet containing an on/off valve.
Humidity (relative) - ratio between the amount of moisture
in the air and the greatest amount of moisture the air could hold at the same
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
Hydrogen - light, colorless, odorless gas: Hydrogen combines
with oxygen to form water.
Hygrometer - instrument for measuring relative humidity in
the atmosphere A hygrometer will save time, frustration and money.
Inbred - (true breed) offspring of plants of the same breed
Inert - chemically non-reactive; inert growing mediums make
it easy to control the chemistry of the nutrient solution.
Intensity - the magnitude of light energy per unit:
Intensity diminishes the farther away from the source.
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.
Kilowatt-hour - measure of electricity used per hour; A
1000- watt HID uses one kilowatt per hour.
Leach - dissolve or wash out soluble components of soil by
heavy watering but can be beneficial to hydroponics systems to flush out excess
Leader - See Meristem
Leaf curl - leaf malformation due lo over-watering, over
fertilization, lack of magnesium, insect or fungus damage or negative tropism.
Leaflet - small immature leaf.
Leggy - abnormally tall, with sparse foliage: Legginess of a
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 arc seed,
seedling, vegetative and floral.
Light mover - a device that moves a lamp back and forth
across the ceiling of a grow 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
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.
Macro-nutrient - one or all of the primary nutrients N-P-K
or the secondary nutrients magnesium and calcium.
Mean - average throughout life; HID's are rated in mean
Meristem - lip of plant growth, branch lip.
Micro-nutrients - also referred to as TRACE ELEMENTS,
including S, Fe, Mn, B, Mb, An and Cu.
Millimeter - thousandth of a meter; approximately .04 inch.
Moisture meter - a fantastic electronic device that measures
the exact moisture content of soil at any given point.
Monochromatic - producing only one color; LP sodium lamps
Mulch - a protective covering of organic compost, old
leaves, etc.: Indoors, mulch keeps soil too moist, and possible fungus could
Nanometer - .000 000 001 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
Nutrient - plant food, essential elements N-P-K, secondary
and trace elements fundamental to plant life.
Ohm's Power Law - a law that expresses the strength of an
electric current: Volts times Amperes equals watts.
Organic - made of, derived from or related to living
Outbred - see hybrid.
Overload - load to excess; A 20-amp circuit drawing 17 amps
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.
Parasite - organism that lives on or in another host
organism: Fungus is a parasite.
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.
pH - a scale from I to 14 that measures the acid-lo-alkaline
balance a growing medium (or anything): In general plants grow best in a range
of 6 to 6.8 pH in soil and 5 to 6.5 for hydroponics.
pH tester - electronic instrument or chemical used to find
where soil or water is on the pH scale.
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 CO2.
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.
Pollen - fine, yellow, dust-like microspores containing male
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 systems become pot bound.
Power surge - interruption of change in flow of electricity.
Primary nutrients - N-P-K.
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.
PVC pipe - plastic (polyvinyl chloride) pipe that is easy to
work with, readily available and used to make most of the gardens on this site.
Pyrethnim - natural insecticide made from the blossoms of
various chrysanthemums: Raids' Pyrethrum is the most effective natural spider
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.
Root-bound - see POT BOUND.
Salt - crystalline compound that results from improper pH or
toxic buildup of fertilizer. Salt will burn plants, preventing them from
Secondary nutrients - calcium (Ca) and magnesium (Mg).
Short circuit - condition that results when wires cross and
forms a circuit. A short circuit will blow fuses.
Socket - threaded, wired holder for a bulb.
Soluble - able to be dissolved in water.
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
Staminate - male, pollen producing.
Starch - complex carbohydrate: Starch is manufactured and
Sterilize - make sterile (super-clean) by removing dirt,
germs and bacteria. A good sterilizer for hydroponic equipment is a 10 percent
bleach to water solution.
Stroboscopic effect - a quick pulsating or flashing of a
Stress - a physical or chemical factor that causes extra
exertion by plants: A stressed plant will not grow as well as a non-stressed
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 dean to function properly.
Sugar - food product of a plant.
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.
Tap root - the main or primary root that grows from the
seed: Lateral roots will branch off the tap root.
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° F (21 to 270 C). Always use tepid water
around plants to facilitate chemical processes and case shock.
Terminal bud - bud at the growing end of the main stem.
Thin - cull or weed out weak, slow growing seedlings.
Tonic life - the amount of time a pesticide or fungicide
remains active or live.
Transformer - a devise in the ballast that transforms
electric current from one voltage to another.
Transpire - give off water vapor and by products via the
Trellis - frame of small boards or PVC (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
Ultraviolet - light with very short wave lengths, out of the
Variety - strain, phenotype (sec 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.
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.
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.