In my HID light garden, a diversity of orchids are cultivated beneath these lights. Subtle differences in illumination and temperature create microclimates that cater to the needs of different genera. Choosing A System Homeowners who consider light gardens often zero in on fluorescent lights. But HID lighting is an alternative that is gaining popularity where a spare room, a large closet or even an unused area of the basement is available. Metal-halide lamps match the tropical sun's color spectrum more closely than other HID lamps.
Fluorescent lights are a boon to the orchid grower.
But these bulbs provide insufficient light to flower those orchids that demand high illumination. While modern fluorescent lighting that offers a spectrum coverage comparable to the sun is available, the tubes lack sufficient output in lumens to coax a big vanda or dendrobium to reach its full bloom potential. Several HlD-type lights are available. High pressure-sodium lamps are somewhat more cost effective and help increase flowering, but their spectrum is more limited. High-pressure sodium lights are also effective when positioned to supplement natural sunlight in a greenhouse.