Grow Lights: High Pressure Sodium
High pressure sodium (HPS) grow lights are one half of a standard HID (high intensity discharge) grow system. Producing a red spectrum light, HPS grow lights are used to replace MH (metal halide) bulbs once your plants have entered the flowering stage. A popular choice for indoor growers for over 50 years, HPS grow lights are inexpensive and can be used by indoor gardeners of all skill levels.
Benefits of HPS Grow Lights
When choosing a high pressure sodium grow light, use the wattage to determine how large of a grow area the lamp can cover.
- 150-Watt HPS grow lights are for very small spaces around 4 square feet. 150W HPS grow lights can be used to grow lettuce, herbs, and other small plants.
- 250-Watt HPS grow lights can cover around 9 square feet of space, making them a good choice for small indoor gardens.
- 400-Watt HPS grow lights are the most commonly used HPS grow bulb, covering around 16 square feet and capable of producing high yields.
- 600-Watt HPS grow lights are the most efficient HPS grow lamp. 600W HPS grow lights produce more light output per Watt used than other wattages and cover around 36 square feet.
- 1000-Watt HPS grow lights are the most powerful and cover a wider area of around 49 square feet.
High pressure sodium grow lights generate heat, so higher wattages should be mounted farther away from your plants. Depending on what plants you are growing, HPS grow lights can be mounted anywhere between 6 to 34 inches away. Make sure to fully research your plants so you can create the ideal growing conditions and not burn your plants by having them too close to the light. You will also need to set up a ventilation system.
While most high pressure sodium grow lights are meant to be used in conjunction with MH bulbs, there are a few instances where these bulbs can be used as a stand-alone grow light. Some HPS grow lights are designed to have a higher blue light spectrum allowing them to also be beneficial to the vegetative stage, eliminating the need for MH grow lights. High pressure sodium lights can also be used without MH bulbs if they are in an area that receives natural sunlight. The sunlight fills in the missing blue light.
To maximize your growing potential, HPS grow lights can be used with timers and light rails. Timers allow you to keep your crop on a schedule, making sure the lights are turned on and off at the same times each day. Light rails slowly move your fixtures along rows, ensuring that plants get an equal amount of light. HPS grow lights should be replaced every 10 to 14 months to ensure plants are getting full light.
Where Can HPS Grow Light Be Used?
High pressure sodium grow lights can be used in grow tents, large grow rooms in homes, and green houses. HPS grow lights are paired with reflector fixtures that are purchased separately. You will need to purchase compatible ballast as well. To find a ballast, you will need to look for one that has the matching ANSI code as your HPS grow light. If you are planning on switching between HPS and MH bulbs, look for a system with a ballast that can operate both bulbs.
Are you looking for the best HPS grow light but are not sure which wattage is right for your grow area? Get help from our grow light experts by calling1-800-624-4488 today!