beginner's corner
With most LED lighting systems, an overlap of a couple
feet is more than enough to create a proper cross-
pattern. Some fast-growing plants, such as tomatoes
or peppers, require higher amounts of light energy and
will require a more intense cross-pattern. For these
types of plants, the LED fixtures should be spaced closer
together. With taller plants, light needs to be directed
deeper into the canopy, which is another key reason a
more focused field of illumination makes sense. Other
plants that require less light, such as lettuce or culinary
herbs like sage, parsley, thyme, etc., will perform just
fine with less aggressive cross-patterns.
One of the biggest differences between cross-patterns
for LEDs verses cross-patterns for HIDs is that LEDs do
not use the same type of reflectors as an HID system.
The reflector of an HID system is the main determining
factor of the lighting system’s footprint. Although some
LED systems have a reflector built in to the system, the
primary and secondary lenses are mainly responsible for
an LED system’s footprint. This is why it is so important for
growers to closely examine the specifications of an LED
lighting system before purchasing.
Comparing horticultural LEDs to one another is a lot
like comparing apples to oranges. They are similar in
some ways, but so different in other ways. Regardless
of the lighting technology being used, some of the
main principles, such as the inverse square law and
how light energy combines in cross-patterns, still
apply. The same benefits growers have received from
utilizing cross-patterns of HID lighting systems are
also applicable to LED lighting systems.
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grow cycle
“
One of the biggest differences
between cross-patterns for LEDs
verses cross-patterns for HIDs is
that LEDs do not use the same type
of reflectors as an HID system.”
As with many aspects of indoor horticulture, experimenting
with light placement and positioning is a key to unlocking
a garden’s full potential, but taking advantage of a value-
added lighting plan from a manufacturer will save time
and maximize efficiency. Horticulturists with multiple LED
lighting systems who use cross-patterns for maximizing
their light energy will be rewarded with better yields and a
higher return on investment.