Sometimes even the sunniest window doesn't provide enough direct light to seedlings or other indoor plants. Most plants need at least eight to 12 hours of light daily, and the only way to achieve that consistently is to use grow lights. Artificial lighting can mean the difference between inferior spindly seedlings that reach for the light and strong, stocky, healthy plants that will do well once transplanted into the garden.
Types of Grow Lights
There are several types of indoor garden grow light
, and choosing which one you will use depends on the types of plants you are growing and how much light they would need if they were planted outside. Standard, or T12, fluorescent tubes are suitable for most indoor growing settings. T5 and T8 fluorescent tubes produce twice the light of standard fluorescent tubes and are sold singly, or as sets of two, four, six or eight. T5 tubes can provide light for wide planting tray systems for plants that grow to 3 feet. Compact fluorescent lights, or CFLs, can supply light for plants that grow to 2 feet and generate very little heat. High-intensity discharge, or HID, lights produce 500 percent more light that standard grow tubes using the same amount of electricity. They are available in two forms: metal halide, that produce the blue light that plants need for foliage growth; and high pressure sodium, whose orange-red light encourages plants to flower.
Grow Light Systems
You can put up a single fluorescent grow light that will handle one seedling tray or small grouping of plants, or a more elaborate two- or three-tier configuration that holds a large number of trays or plants. Fluorescent tubes emit very little heat, making them safe to place very close to plants, which maximizes the amount of light being produced. Replacement tubes are available everywhere, and the fixtures are lightweight, and easy to assemble and maintain.
Selecting the Right Grow Light
Use T12 fluorescent lights to start seedlings and to grow plants that would tolerate some shade if grown outside, such as lettuce, spinach and herbs. Expect to get 20,000 hours of use from them. Higher output fluorescent T8 and T5 lights are a good primary light source for all indoor growing purposes, from starting seeds and rooting plant cuttings to growing leafy plants and flowers. CFLs are useful for larger plants and cuttings, and focus light more directly onto plants. Both CFLs and higher output fluorescent bulbs last about 10,000 hours.
Considerations
There are lot of grow lights for sale
online. While inexpensive to buy, standard incandescent light bulbs provide the least amount of useful light to plants. They are best used to supplement inadequate sunlight for individual indoor plants, and they generate very little lumen output for the amount of power they use. LED grow lights are the most recent addition to the grow-light family, and perform about the same as cheaper fluorescent tubes.