Halide Bulbs (aka: MH)
Many gardeners recommend metal halide
grow lights above all others. The reason being it's
excellent spectral distribution. Metal halide bulbs
emulate bright summer sunlight and contain all the
energy peaks at wavelengths of the visible spectrum. To
plants this means quality simulated sunlight and
photosynthesis at a level much higher than that which
fluorescent lamps can achieve.
Use MH bulbs during the green
vegetative stage of your plants' growth cycle.
The spectral output of HID bulbs varies
drastically. Metal Halide bulbs come in all spectrums,
from specialized MH bulbs that are made specifically for
early vegetative growth, to equally specialized bulbs
that target the heart of your plants flowering cycle.
The higher the "K" (kelvin units) number listed with the
bulb, the 'cooler' the bulb spectrum is. Cool spectrum
bulbs (6.4k-10k) are best used for different parts of
vegetative growth, while warm bulbs (2700-3000k) are
better for fruiting/flowering.
To keep it simple, start with bulbs
that are in the range of 6400k (this applies to both
T5's and HID lights), and finish with a bulb that's near
2700-3000k. (If you want to fully "explore" the science
of indoor gardening, we've got customers that change
their bulbs as many as 4 or 5 times during one growth
cycle, but this is not necessary for good results.) Our
best selling vegetative bulbs are
Deluxe, Hortilux Blue,
standard MH bulbs.
In addition, metal halide grow lights
have good lumen maintenance and long life expectancy.
Having good lumen maintenance means that as a lamp ages,
its decline in lumen output is very gradual. After 12
months of use at 18 hours per day, a 1000 watt metal
halide lamp should be replaced as it is only about 85%
as bright as the day you bought it. Halide is the best
bulb technology available for achieving the highest
level of plant and flower growth. They allow the
flexibility of multi-crop, multi-season indoor
Sodium Bulbs (aka: HPS)
High pressure sodium plant lights are
the only growlights comparable to metal halide bulbs.
They have good spectral distribution, but sodium lights
cannot compare to halide in the blue end of the
Use HPS bulbs during (or to
initiate) the budding, flowering and fruiting stages of
Sodium grow lights are particularly
high in the yellow and red regions of the spectrum. This
is the type of light fruiting and flowering plants like
best. Because of the focus on red light, some varieties
of plants grown with sodium lights alone can become
elongated and leggy.
Sodium grow lights do, on the other
hand, stimulate flower and fruit production more
efficiently than metal halide bulbs, making them an
important light source best used in conjunction with
metal halide either in addition to, or cycled together.
High Pressure Sodium bulbs also have a much longer life
expectancy than metal halides, lasting up to two (2)
Our best selling HPS (flowering) bulbs
Agrosun Red, and
If you have one of these types of grow
light systems, but need to move into the other type, you
don't have to buy a whole new lighting system!!! We've
got conversion grow light bulbs to accommodate your
HID Conversion bulbs make it possible
to run a halide bulb from your sodium ballast or a
sodium bulb from your halide ballast. So you could run a
halide to bring your plants through the vegetative stage
then switch to a sodium conversion bulb to finish 'em
off through flowering.
The newest addition to the HID bulb
category is the "Dual-Spectrum" bulbs.
These are very intricately designed
bulbs that contain the inner workings of both MH, and
HPS bulbs, both artistically installed into the same
glass outer housing of a single bulb.
This is a growing category, and we'll
be adding more dual-spectrum options over time. When you
light one of these bulbs, it's a thing of true beauty.
Even with all of the advancement in bulb spectral output
technology, this is still the clearest example of a true
full-spectrum bulb. Dual-spectrum bulbs can be used in
all stages of growth, and will give you excellent
results every time. Plants love these bulbs, and grow
and develop very nicely as a result.
We've found that plants respond to LED
lights similar to T5 fluorescent fixtures. They result
in tight inter-nodal growth, and short stocky, strong
plants. The plants do look a little different - the
leafs tend to curl down. But the leaves are thicker and
a more healthy shade of green.
Vegetative growth is a little slower
compared to a 400 watt HPS light but are healthy and
progress normally. Fruiting and flowering is also
slightly slower but healthy and strong, with
surprisingly dense development. The fruit and flowers
are more realistic in color and are beautiful.
Fluorescent bulbs have come a long way!
The old T12's are being phased out of the marketplace,
and replaced with T8, and T5 bulbs and fixtures.
T5's are the best quality fluorescent
lights for horticultural purposes, and work great for
everything from cloning or seedling germinating, to the
early vegetative stages of growth for larger plants.
T5's excel at vegetative growth up to about 12" tall.
For leafy green and herb gardens,
they simply can't be beat. They also work great for
bonsai trees, houseplants, and orchids.
The light quality from T5 lights is
gentle, and doesn't produce much heat so they can be
used in small areas. The best bulbs for vegetative
growth are the 6500k bulbs, and for orchids, or other
short flowering plants, the 2700k bulbs work best. You
can also mix the bulbs to produce a full-spectrum light.
T5 fluorescents put out 5000 lumens per
tube and have solid state electronic ballasts that do
not emit heat, noise or vibration.
Compact Fluorescents are a proven
success as horticultural lighting. In their first year
on the market, they have proven themselves as a perfect
grow light for seedlings, cuttings and small plants.
Compact Fluorescent bulbs are ideal for small spaces as
they do not produce much heat or use much electricity.
For fruiting or flowering plants, the 2700K warm bulb is
superb. For plants taller than a foot, regular
fluorescent tubes can be supplemented on the plant
OK, now that we've got an idea about the
kind of grow light bulbs we want, let's take a look at the
grow light systems.
Or, if you just need replacement
growlight bulbs, go right to our