Houseplants are wonderful for decorating. They liven up a room and give your house a boost of oxygen. However, your home may not be as well-lit as you and your houseplants would prefer, or you may have houseplants that need more light than an indoor placement allows. If you have been waiting and waiting for your flowering houseplant to bloom, or if you are trying to start some spouts from seed that need more light than the winter sun is providing, consider adding some artificial light.
Plants convert light into energy to grow and to flower. The intensity, duration and quality of light a plant receives will determine how well it grows. The intensity of the light will influence how much plant food is manufactured, the length of the stem, the leaf color and flowering. Southern exposure is the best possible light for indoor plants. Eastern and western exposure are about 60 percent as intense as southern exposure, and northern exposure is only 20 percent as intense. Sunlight naturally supplies the red and blue rays your houseplant requires, but if they are not receiving enough sunlight, you can help them with artificial light.
When your indoor plant becomes pale in color with long stems and few leaves or no flowers, it is probably not getting enough natural light. If you can find it a place in your home where it will receive more natural light, you can try different placements to see if your plant will do better. Another option is using artificial light to help your plant. Sometimes a regular reading light will offer enough of a boost if your plant is receiving a fair amount of natural light and is a plant that does not require an intense of an amount of light. However, if your plant continues to wilt and appear spindly, you may want to consider exposing it to more intense and longer hours of light under artificial lighting.
Incandescent bulbs offer red rays but not enough blue. They burn hot and need to be properly placed so as not to hurt the plants with their heat. They are also less cost efficient than other bulbs. Fluorescent bulbs are a cooler bulb that uses less energy and supplies more blue rays. Depending on the plant and its specific needs, you may choose one or the other. The Department of Floriculture and Ornamental Horticulture at Cornell University recommends a combination of the two for the best results. The University of Missouri suggests 30 watts of incandescent lights for every 100 watts of fluorescent lights. Other lights used for indoor plants that are not getting enough natural light are warm-white fluorescent lights, spot lights and flood lights. However, they are not as effective as the combination of incandescent and fluorescent lights.
Different plants require different intensities of light. Generally speaking, there are low-light plants, medium-light plants and high-light plants. If you cannot give your plants enough natural light, you can offer them intensity from artificial lights. It will help you to know how much light your plant naturally requires. Low-light plants need only one fluorescent tube and will do better than other plants if there is little natural light available. Medium-light plants require at least two tubes of fluorescent lights. High-light plants should receive at least three or four tubes of fluorescent light, but still may do poorly.
Increase the light intensity by placing your plants on a light, reflective surface. Also, make sure your plants are not crowded and shading one another. Give them plenty of room to ensure they are all receiving ample exposure.
If your houseplants are not getting enough intensity, duration under artificial lights can be increased to help them get enough light. As with intensity, different plants require different durations of light. Short-day plants do best with 12 hours of light and 12 hours of dark. Long-day plants prefer 16 hours of light. Too much light can be as damaging as not enough light. Leaves may become pale, turn brown or appear sunburned if a plant has too much light. Most flowering plants are indifferent to duration, but some will be adversely affected by too long of a day. All plants should have at least eight hours of dark to grow properly.