“Birth, life, and death -- each took
place on the hidden side of a leaf.”
Lighting- A Primer
There are three primary
grow light choices for hydroponics gardening: Fluorescent, Metal Halide (MH),
and High Pressure Sodium (HPS).
Fluorescent grow lights give off low heat, but
consequently, lower light output. Full-spectrum fluorescent lights are fine for
ornamental houseplants and leafy produce like lettuce and spinach, and for
herbs. They also work great for starting seedlings, cuttings, and clones. They
are the cheapest lights you can buy for a hydroponics garden, and are nice and
COOL. You can find small "Gro Sticks" at Walmart for $10 for your seedling
BUT, fluoros just don't have the proper spectrum needed for fruiting vegetables
and flowering plants. New T5 and T8 high output systems are now available that
produce enough lumens to grow various plants to maturity, but they just don't
provide the most ideal lighting for optimum production of fruits and flowers.
If you're pretty sure you're going to limit your hydroponics gardens to leafy
veggies... lettuces, chard, spinach, herbs... then go ahead with a T5 fixture.
But if you think you might one day grow veggies or flowers... then go with a
High Intensity Discharge (HID) lamp. It can be used for all types of hydroponics
LITE TEMPERATURE CHART
HID LAMPS COME IN 2 TYPES:
Metal-halide lamps produce high light output
for their compact size, making them a powerful and efficient gardening light
source. Rare earth metal salts are added to a mercury vapor lamp, which improves
luminous efficiency. Like most HID lamps, metal halide lamps operate under high
pressure and temperature, and require special fixtures to operate safely. Since
the lamp is small compared to a fluorescent or incandescent lamp of the same
light level, a reflector is essential to direct the light efficiently onto your
Metal Halide grow lights are
green/blue/violet-oriented in the spectrum, depending upon the Kelvin
temperature, and is the best light when natural sunlight is not available. It
also is particularly appropriate during the vegetative growth stages. If you can
only afford one lamp, get a 400 or 600 watt MH.
HIGH PRESSURE SODIUM
High-pressure sodium (HPS) lamps are also a
small but highly efficient light source. They contain additional elements such
as mercury, and produce a dark pink glow when first struck, and a pinkish orange
light when warmed. High Pressure Sodium grow lights are red/orange-oriented in
the spectrum and the superlative lamp for secondary or supplemental lighting and
promotes budding, flowering and fruiting. A 400 or 600 watt HPS makes a fine
addition to your hydroponics system. The best solution is to use a MH lamp for
the vegetative stage of growth, and switch to an HPS for the flowering and
WHAT? CAN'T AFFORD TWO
We have a great solution for that problem here:
Hydro Tip of the Month-
Looking for the perfect frame in which to place your hydro system? Look no
PVC HYDRO STAND .
We hope you have enjoyed this issue of The Urban Farmer Ezine. Each month, we will bring you another inspiring photo, gardening quote or idea, plus fresh new hydroponics news, techniques & products.
Insiders tips to get you growing...
~Stella and Simon from