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Lighting is one of the most important factors when it comes to plant growth. For any kind of reasonable yield, you need a minimum of 400W. Growers are currently leaning more and more towards 1000W or 600W as the standard for growing rooms equipped with the latest technology. Lighting is essential in the plant’s ability to assimilate minerals and CO2.

Indoors, lighting is almost always one of the main impediments to plant growth. Plants can grow no faster than the most limiting factor will permit.
There are essentially two types of high intensity discharge (HID) lamps used in horticulture: metal halide (MH) lamps and high-pressure sodium (HPS) lamps. MH lamps generate light at the blue end of the spectrum, which is very close to the spring and summer sun, whereas HPS lamps lean more towards red and yellow/green, which is closer to the fall sun. As a result, we recommend using MH lamps in your plants’ growth stage, and HPS lamps in their flowering stage to reproduce natural light as closely as possible. However, if you have to choose between the two types of lamps, a number of studies have shown that the HPS lamp comes out ahead, all uses combined, not only in terms of energy efficiency (Lumens) but also in terms of durability.

HPS = flowering

MH = growth

We offer our customers a wide range of products in this regard, and advice on the optimal use of each one:


  • Fluorescent tubes: for sowing and cutting.
  • 2,700 K or 5,000 K 105W compact fluorescents.
  • MH 400W and 1000W lamps: for plant growth.
  • HPS 400W, 600W and 1000W: for flowering.


  • HPS 400W, 430W, 600W and 1000W Hortilux bulbs emit a spectrum consisting of 30% blue and 70% red, as well as the highest Lumen/Watt ratio.
  • Conversion bulbs provide HPS lighting with MH ballast and vice versa.
  • Super MH bulbs generate up to 10% more lumens than standard MH bulbs.
  • The new Hortilux Blue (Daylight) Super MH growth bulbs. These tubular bulbs are available in 400W and 1000W. They provide an optimal range of spectral energy.

It should be noted that the intensity of lamps calculated in Watts is not cumulative. Thus, three 400W lamps are not more intense than one of 1000W. Two values need to be taken into consideration in determining the amount of lighting: the number of Watts per square foot and the intensity of the lamp (in Watts). The ideal is 50W/square foot. Thus, a 1000W lamp covers 20 square feet, while a 400W lamp covers 8 square feet. But most importantly, the 20 square feet covered by the 1000W lamp receive more light.

HID lamps generate an average of 3.4 BTU per Watt. The use of Air Cooled ventilated reflectors can help to significantly reduce heat emissions from the bulbs.

Finally, for optimal yield, bulbs need to be replaced in a timely fashion (maximum of 8 months for an MH and 12 months for an HPS).

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