All Plants Require Light in Order to Thrive
All plants require light in order to thrive. The basic life process of the plant kingdom is photosynthesis, wherein light-sensitive cells in plant leaves convert light energy into chemical energy to feed the plant. Because of this, indoor gardening requires planning and the use of proper equipment in order to be successful. When growing indoors hydroponically, or even in good old-fashioned soil, there are many considerations to be taken into account, but of primary concern is the type of artificial lighting to be used.
Traditionally, indoor horticulture required the use of bulky gas-discharge lamps in order to produce light of sufficient intensity and of the proper wavelength to grow plants. Regular consumer lighting fixtures used in homes and offices do not produce light of the correct spectrum and intensity for this purpose. These types of high-output lamps consume excessive amounts of energy and produce massive amounts of waste heat, which require the additional expense of sophisticated ventilation systems to draw off all the wasted heat produced by the lamps. However, recent advances in LED lighting technology promise to change this paradigm of indoor gardening for the better, by exponentially reducing the amount of energy required per unit of light produced and by reducing or eliminating the need for complex ventilation systems in indoor gardens.
LED stands for Light Emitting Diode, which is a simple electronic semi-conductor device that has been around since the 1960s. An LED is a diode, basically a one-way electronic switch, that produces light through a phenomenon called electroluminescence. A diode is a device constructed of two materials with differing levels of limited electrical conductivity, hence the word semi-conductor, with one of the materials having a net positive charge and the other having a net negative charge. Diodes are used much like transistors and resistors to regulate current flow in various electronic devices and machines. When a current is passed through a diode from the negative (N-type) to the positive (P-type) material, some the electrons in the current flow are captured by empty spaces in the atomic structure of the P-type material. This, as a side-effect, discharges the excess energy by producing photons of light.
The light produced by early LEDs was not very bright, being of a very long (red) wavelength. The good news is that it takes a miniscule amount of current to produce a unit of light. The better news, from the standpoint of the indoor gardener, is that as the science behind the technology has advanced, the output capabilities of this very efficient lighting system makes LED grow lights a viable alternative to the old gas-discharge systems for indoor horticulture.
LED grow lights have been commercially available for a number of years now and, as the technology and production infrastructure continues to expand, the cost of these super-efficient LED lighting systems will surely come down. The advantages of LEDs are clear: They provide highly reduced energy consumption, the elimination of waste-heat and long-term cost-savings through the extreme durability of these devices. They can be rated to last as many as 100,000 hours, or 12 years under normal usage conditions.