Six hours of full-spectrum direct light is a requirement for most greenhouses. Supplemental lighting is typically necessary for commercial and hobby settings. Artificial lights promote healthy growth and can increase crop yield. Growers also need photoperiod control lighting. This type of lighting refers to the number of hours the plants receive light over 24 hours. Photoperiod control lighting is often used to trigger or delay flowering in greenhouses.
High-Pressure Sodium Lighting
High-pressure sodium bulbs produce an orange-red light that promoted budding and flowering. These types of light fixtures are typically used later in the plant’s growth cycle.
Some advantages of high-pressure sodium fixtures are energy efficiency. The bulbs are 7x more efficient than incandescent lights. The lights may also provide photosynthetically active radiation (PAR) to support healthy plant growth.
It does take high-pressure sodium lighting several minutes to warm up and cool down, making them energy-inefficient in areas where the lights are frequently turned on and off. Bulb placement is also crucial. The lights should be around 30 to 36 inches above the plants.
Did you know we have an in-depth comparison of HPS vs LEDs for Greenhouses? We cover the benefits of both HPS and LED for your plants and the energy savings you should expect to see.
Programmable and Fixed LED Lights
Light-emitting diode (LED) lights have an incredibly long lifespan, around 50,000 hours. The bulbs are energy-efficient since most of the energy is turned into light and not heat. The energy savings with LEDs can be 70% and higher, compared to high-intensity discharge (HID) lights.
Since LEDs do not have a warm-up or cool-down time, growers see additional energy savings, of up to 70%. The bulbs are also free of mercury, making them easy to recycle without paying a hazardous material fee.
LEDs are also programmable with controls. Growers can set times for the lights to automatically turn on and off or even adjust the color temperature. LEDs can be used from seedling to the final growth stage.
Ceramic Metal Halide Lighting
Ceramic metal halide bulbs produce a blue light that works well in areas that are not receiving a lot of natural sunlight. The bulbs typically last between 8,000 to 15,000 hours and are up to five times more efficient than incandescent lights.
The lights are typically used during the plant’s early growth stages. The blue light encourages healthy greenery. The downside is the long warm-up and cool-down times that makes them less energy-efficient than LEDs.
T5 bulbs are common in greenhouses. Fluorescent lights use less energy than halides and sodium-high-pressure bulbs. T5s have an average lifespan of around 50,000 hours and are environmentally friendly. The lights can also be used from seedling to the final growth stage.
The “T” refers to the bulb shape and the “5” references the fixture’s size. The slim tubes have a high lumens output, produce full-spectrum light, and emit low heat. Growers can place the lights as low as 6 inches above the plants without worrying about burning the leaves.
Learn More About Greenhouse Lighting
Greenhouse lighting options are often confusing. Some types of bulbs are geared for a specific stage of a plant’s growth. To learn more about LEDs and other types of greenhouse lighting, contact the Action Services Group lighting experts today.