We have developed general guidelines to follow when hanging the LEDs. For instance, a
single LGM5 should be mounted 28-18″ from the top or sides of your plants. One of the
few common characteristics of traditional lighting and LED lighting is that they both follow
the Inverse Square law for light intensity. The light intensity decreases as the square of the
distance from the light. For example, an LGM5 hung at 36″ will have approximately 1/4 of
the intensity of the LGM5 at 18″. This is a large range of light intensity that enables
growers to adjust for the needs of different plants. Because 100% of the light emitted is
being used by your plants (as opposed to 10% of the light from traditional lighting) there is
a danger of giving your plants too much light.
Hanging the bar further away will increase your coverage area but decrease the
intensity. Hanging the bar closer will decrease your coverage area but increase your light
intensity. The exact mounting height that will satisfy your plant’s light requirements can
only be judged by observing your plants reaction to the light, and of course, good old
fashioned common sense. Changes in light intensity should be gradual. A plant that
naturally grows in the deep shade of the rainforest will likely suffer if an LGM5 is placed at
20 inches over the plant. A plant that naturally grows in the bright sunlight may thrive at 20
inches. Like all light sources, the bars will need to be raised to maintain this distance from
the plant.
Remember that plants will generally survive a period of low light but too much light may
permanently damage them. This is why we recommend that you start your bars off close
to the maximum distance recommended and then watch for signs to determine if the bars
should be lowered. If you have a nearby window and you see your plants leaning toward
the window you may want to lower the bar. If there is not another light source and the
plants are leaning away from the LEDs it could be a sign that they are getting too much
light. Not enough light will cause leaves to turn yellow but too much light will bleach the
leaves. If the bar needs to be closer you may see reduced leaf size and longer internodal
lengths. If upward growth stops the lights should likely be raised. Once you have
determined a distance that is promoting the vigorous growth you are looking for you can
assume that this is the optimal mounting height.
Different plants have diverse needs and there are many environmental factors that can also
cause the above symptoms. If you are having difficulties determining whether your bars
are mounted properly please do not hesitate to call or email for product support.
Representatives will ask for basic information about your grow area and research the light
requirements of your garden or help troubleshoot environmental factors. We are available
seven days a week for your convenience. –AL