The most common grow lights
Modern indoor plant cultivation usually involves at least one of three artificial light sources: HID, CFL, and/or LED. Growers often use a combination of grow lights. In this article, we will focus on the most widely used plant-growing lights of the 21st century.
HID, or high-intensity discharge lamps, are fixtures used to grow all kinds of plants indoors by everyone from beginners to professional cultivators—at least since the early 90s of the last century. Over the years, lamps have become more efficient, ballasts digital, and reflectors larger and better, but the basic principles of growing plants with this type of artificial light remain the same: MH for vegetative growth and HPS for flowering.
CFL, or compact fluorescent lighting, is highly effective in the cool-white spectrum as an alternative to an MH bulb. This is achieved by suspending the CFL 10 cm above the plant canopy. CFLs run cool and can be positioned very close to plants without burning the leaves. They also raise the temperature in growing rooms only slightly. This makes CFLs perfect for seedlings, cuttings, and use during vegetative growth. Sometimes CFLs are the only option for microgrowers. Unfortunately, CFLs do not deliver impressive light output or PAR. Worse still, CFLs are not very effective for flowering. Some plants need far more intense lighting during flowering than CFLs can provide. Expect low yields and loose buds from CFL lamps during the flowering stage.
LED, or light-emitting diode, is an emerging technology that aims to end HID's dominance. The latest generation of LED systems can now produce fruit of comparable and, in some cases, higher quality than average HID systems. PAR, or photosynthetically active radiation, is considered the most important metric. The latest LED systems have finally achieved parity with traditional HID lighting systems.
High-efficiency LED kits that consume 350-400 W and can outperform a full-spectrum 600 W MH and HPS setup require a larger investment, but have a considerably longer service life. Some models really can do everything. The best systems do not generate high temperatures and are extremely economical in the long term. Hanging distances vary widely, so buyers must take care and always check the manufacturer's instructions.
HID lamps rated at 400 W and 600 W are best suited to growing plants indoors. Lamps should be hung level. The optimal light height is between 30 and 60 cm above the plant canopy. This means carefully securing the reflector to the ceiling or the roof of the grow tent with ratchet hangers or rope hangers.
It is best to use lighting fixtures that can easily be adjusted and moved as the plants mature and grow taller. For seedlings and cuttings, however, a 600W MH lamp may be too powerful and would be better positioned more than 60 cm above the top of the plants.
Fixed lights with a horizontal bulb mounted in a clean, open reflector are the professional standard for growing. Ideally, use a large reflector, or one as large as the growing space will accommodate, with a wide spread to make use of the entire area.
If you need a grow light, it is not difficult to find one. The main thing is to determine the right parameters and choose a lamp with the appropriate power.
