Plants
depend on photosynthesis for growth and this in turn depends on sunlight. The
Sun emits light ranging in wavelength from ultraviolet with the shortest
wavelength at about 280 nanometers to infrared with a wavelength of about 700
nanometers. This is known as full spectrum and plants benefit when exposed to
Sunlight since the process of photosynthesis needs indigo, violet, some
infrared, red and orange colors to grow properly. Growers using hydroponics
under controlled conditions make use of artificial full spectrum or part
spectrum lighting concentrated in these ranges to promote growth and obtain
better yields.
The
most common light sources are low pressure sodium vapor lamps, mercury halide
and halogen. However, these emit light with limited spectra with sodium vapor
emitting yellow light and mercury lights emitting blue-green light. Most of the
energy is lost and only a small part is used. This means lower productivity and
higher energy costs. The better alternative is to get full spectrum LED grow lights for sale
from quality manufacturers. Such selected LEDs emit full spectrum light in the
correct balance, nearly mimicking Sunlight.
LED
lamps consume less power, run cooler and have a life of about 100000 hours
depending on the control circuitry. They also have a flatter light spread and a
directional beam, avoiding the use of reflectors and wastage of light. About
400 to 800 low cost 3W full spectrum LEDs can be arranged in a flat panel to
give uniform light output over an area of 3 meters x 3 meters , with the lumen
output at 600 watt power consumption being the same as the output of other
lamps consuming 1500 or 2000 watts because LEDs have the highest
efficiency. With full spectrum LEDs on
the scene, it is no contest and all other lamps become obsolete for hydroponics
purposes.
