Grow Lights for Plants: How to Use Grow Lights for Plants

Grow lights are artificial lights used to help indoor plants grow year-round. Grow lights come in a variety of color spectrum and light intensity options to cater to the needs of different types of plants. Indoor grow lights are essential gardening tools that allow houseplants to get enough light even in rooms without access to natural sunlight.

Grow lights convert electrical energy into photons, light particles that stimulate photosynthesis and encourage plant growth. The best light sources for photosynthesis include a variety of wavelengths that the human eye perceives as color. Red light works best for fruiting and flowering plants, while blue light enhances vegetative growth.

There are a few main types of grow light options to consider for your indoor garden.

1. 1. Fluorescent grow lights: Fluorescent grow lights come in a variety of forms, including tube lights and compact fluorescent lights (CFL). Although they produce a full spectrum of light for plants, fluorescent bulbs are less energy-efficient than LED bulbs and they can have a harmful heat output.
2. 2. Incandescent grow lights: Although some growers use incandescent bulbs, this type of grow light has a high amount of heat output that can burn plants. Incandescent lights are cheaper than other grow light options, but they use more energy and burn out quicker.
3. 3. LED grow lights: LED (light-emitting diodes) lights have a longer lifespan than most other types of grow lights. They are energy-efficient and have a low heat output. LED lights typically come in two styles: LED grow light bulbs and larger LED grow light fixtures.
4. 4. HID grow lights: HID (high-intensity discharge) grow lights replicate natural light better than other types of grow lights. These high-output lights are expensive and most often used in commercial grow rooms. There are two main types of HID grow lights: high-pressure sodium (HPS) lights, which emit a red color, and ceramic metal halide (CMH) lights, which produce a blue color perfect for seed starting.

Use grow lights to help your indoor plants grow quicker and healthier.

1. 1. Choose your equipment. Select the style of light you think will work best for your houseplants or herb garden. Fluorescent and HID grow lights often require ballasts to regulate electrical outputs. Full-spectrum grow lights are a good option for most indoor plants. If you have several houseplants, consider using a larger grow lamp, a panel of lights, or a reflector for supplemental light to reach the bottom of leaves.
2. 2. Set up your lights. The ideal lighting levels depend on the types of plants you have in your indoor garden. Although some plants thrive in low-light conditions, most require bright light—particularly succulents and flowering plants.
3. 3. Monitor the temperature from your lights. Depending on the wattage of your light sources, grow lights can burn houseplants. Place incandescent lights at least two feet away from your plants. Keep fluorescent and HID grow lights at least twelve inches away from plants. With a low heat output, LED grow lights can typically get as close as six inches to houseplants without harming them.
4. 4. Install a timer. Constant light output prevents plants from experiencing a normal light-dark cycle and ultimately harms them. Use a timer to regulate the amount of light your houseplants receive from your grow lights. Make sure your plants get between eight to sixteen hours of light and at least eight hours of darkness.

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