Light Requirements for Hydroponic Veggies

Hydroponic veggies are plants that are cultivated in water instead of soil. The gardening of hydroponic plants takes place indoors and therefore requires some form of artificial lighting in the place of sunlight. Several types of lighting will benefit hydroponic plants and encourage growth, but they all have the same basic components.


High-intensity discharge, or HID, lights are the most effective and energy-efficient type of lighting available for hydroponic gardening. HID lights are bright and intense, providing the plants with a light source much like sunlight. HID grow lights can be purchased at gardening or home improvement stores. Each individual light provides a lot of light for your hydroponic veggies, especially when used in conjunction with other lighting tools, such as reflectors.

Reflectors and Ballasts

To get the most out of your HID grow lights, you will need some additional lighting equipment. Grow lights are run by a ballast, which is a metal box that contains the necessary components to heat and run each lamp. Since ballasts are designed by wattage, you must have separate ballasts for each wattage of lamp you are using with your hydroponics. Reflectors are another essential piece of equipment. They can be placed around the room, increasing the effectiveness of each HID bulb, reducing the number of lights you actually need for your hydroponic garden.

Cool Lights

While it may be tempting to try to light your hydroponic veggies with standard light bulbs, there is a reason that HID bulbs work best. HID lights create a lot of light without generating heat. Incandescent light bulbs, on the other hand, create a lot of heat, which can be detrimental to hydroponic veggies. Too much heat will prevent the growth and development of the plants, so if you choose to use standard incandescent bulbs, your lighting set-up will also require cooling fans.

Proper Placement & Lighting Changes

Plants do not benefit from light that is not directly aimed on them, so it is important to place your lights correctly for your hydroponic veggies to grow. When starting with seedlings, lights can be hung directly over them, so that they hover 2-4 inches above the top of the plant. The lights can be moved up as the plant grows to maintain the same distance between the light and the plant. Different stages of hydroponic vegetables' development also benefit from different types of lighting. While veggies are first growing and developing stems and leaves, metal halide HID lamps, which create a blue light spectrum, are most beneficial. When the vegetables begin to form, HPS lamps, which produce a red light spectrum, are the most effective.

Keywords: hydroponic veggies, hydroponic garden, grow lights

About this Author

Alexis Lawrence is a freelance writer, filmmaker and photographer with extensive experience in digital video, book publishing and graphic design. An avid traveler, Lawrence has visited at least 10 cities on each inhabitable continent. She has attended several universities and holds a Bachelor of Science in English.