Lighting choices are critical to any indoor growing operation. Two popular lighting options that many cannabis growers use are light-emitting diodes (LEDs) and high-pressure sodium (HPS). There are advantages and disadvantages to each of these options, and the decision of which is better comes down to personal preference and the specific needs of the growing operation. Here is a look at some of the key differences between these popular lighting setups.
LEDs have been around since the 1960s, but recent technology over the last decade has made this style of light a common favorite with indoor growers. This style of lighting is very efficient and has the ability to convert almost all of the power used for operation into light energy. LED fixtures are designed to require little to no maintenance and generate less heat than other types of lighting. Older styles of LED lights may not produce the appropriate spectrum of light necessary for plant growth, but more recent designs have nearly eliminated this issue.
- Very efficient and cost effective
- Operate at lower temperatures, reducing potential fire hazards in indoor grows
- Lighting fixtures are compact and easy to set up
- Low potential for heat damage to plants
- Higher upfront cost
- Older styles may not provide proper light spectrum for growth
- Low levels of heat emitted may require supplementation by a heat light
HPS lighting options have also existed for some time and are another popular and productive light for indoor growing operations. HPS lights emits a huge amount of light that is great for plants, especially during the flowering cycle, but the high heat levels produced can limit effectiveness in vegetative growth cycles.  HPS lighting systems are a common and viable method for consistent indoor plant growth.
- Cheaper initial cost than LED.
- High light output can create great yields during flowering stage
- Lighting options are more standardized than in comparison to LED
- Use much more electricity than LED and more expensive to operate.
- Generate high heat which can pose a potential fire and venting hazard
- Contain wavelengths not needed for plant growth, which cause leaves to heat, affecting proper metabolic temperatures
- Bulbs burn out and need to be replaced
Bilodeau, Samuel, et al. “An Update on Plant Photobiology and Implications for Cannabis Production.” Front Plant Sci, vol.10, 2019: 296. Journal Impact Factor = 4.298, Times Cited = 1.
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