Maximum Yield USA 2015 April | Page 54

the right light for vegetative growth “Lighting manufacturers have created many different, vegetativespecific MH lamps designed to emit a spectrum catered to vegetative growth.” the plant canopy, the more light energy can be used by the plants. This more efficient use of light energy creates plants with tighter node spacing. Short, bushy plants are the most sought after for indoor horticulture and will generally produce higher yields than tall, lanky plants. Due to their high output, even light dispersion and low heat signature capabilities, T5 fluorescent fixtures have become one of the most popular lighting choices for vegetative growth. Light-Emitting Diodes Some of the newest technologies growers have adapted for vegetative growth are light-emitting diodes (LEDs). LEDs provide many advantages for indoor gardens. They have an extremely low heat signature, which means plants can be placed close to the light source, and some LEDs also have a customized spectral output. In other words, LED fixtures can be made to produce a particular spectrum suitable for various types of growth. For the purpose of vegetative growth, many LED manufacturers produce fixtures with a higher output of blue spectrum. LEDs, like T5 fluorescents, can produce even growth in terms of both node spacing and plant canopy uniformity. Another large advantage of LED lighting is longevity. LEDs will not need bulb replacement like HID or fluorescent lighting. They can be used for 10-15 years before requiring replacement. 52 Maximum Yield USA  |  April 2015