High Pressure Sodium (HPS)

Last updated: May 18, 2021

What Does High Pressure Sodium (HPS) Mean?

A high pressure sodium (HPS) light is a type of grow light that is commonly used for indoor gardening. This particular light stimulates plant growth by diffusing the portion of the electromagnetic spectrum that is ideal for the whole process of photosynthesis. High pressure sodium lights are also used to prevent the plants from growing overly spindly and long. It mimics general outdoor conditions, especially as far as color and temperature is concerned.

HPS bulbs, along with other types of grow lights such as metal halide (MH) and mercury vapor (MV) are known as high intensity discharge (HID) lights.

High Intensity Discharge (HID) Bulb


Maximum Yield Explains High Pressure Sodium (HPS)

In 1868, Andrei Famintsyn was the first botanist to adopt a high pressure sodium light for indoor gardening. This grow light is commonly favored during the reproductive and vegetative stages of gardening. In these cases, growers may want to adjust the light spectrum range to enhance growth. High pressure sodium bulbs emit light primarily from the yellow to red parts of the visible spectrum.

Unlike metal halide growth lights, high pressure sodium lights have fewer carbon emissions. They also tend to last longer. Most high pressure sodium light systems normally last between 12,000 to 24,000 hours.

A 400W bulb can easily cover a gardening area of approximately 15 square feet, while a 1000W bulb can be used on a growing area of around 7x7 feet.

For a long time, HPS bulbs were the bulb of choice for many cannabis growers. However, newer technologies like light emitting diodes (LEDs) and ceramic metal halide (CMH) are providing more competition for HPS manufacturers. In an effort to compete, HPS manufacturers now offer double-ended lighting technology, which are more powerful and last longer than their single-ended counterparts.

HPS bulbs are sometimes available as a conversion bulb, meaning they can be operated in a metal halide ballast, or vice-versa.


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