Light wavelengths in the range of 400 to 700 nanometers (nm) are consider ideal for plants. More specifically, 440 nm blue light, 660 nm red light and 730 nm far red light are important for good photosynthesis and plant growth. Some light fixtures give off pink/purple visible light, but others can be adjusted to give off warm or cool white visible light, which is more typical for home lighting, while still providing the necessary light spectrum for plant growth.
One example of an LED light strip providing these wavelengths, is the Lightimetunnel LED Plant Grow Light Strips – Full Spectrum, cost $37.99 for 4-15” light strips, which can be connected end to end. These types of light strips are becoming the standard for indoor production of lettuce, greens or herbs and can easily be used when growing your transplants for next year’s garden. Many similar products by other manufacturers are also good options.
An example of a floor lamp for larger houseplants is the AgroBrite Hydrofarm Floor Plant Light, cost $59.09, but many good floor light options are available. Others have three or more light heads that can be directed and adjusted to provide light for several plants.
Tips on Using Supplemental Lighting
When growing transplants or seedlings in the winter months, position lights 3-6 inches above plant leaves and raise the lights as plants grow. Follow the instructions for your light system to determine correct placement and look for the signs of low light in plant growth listed above to determine if your lights are too far away.