When growing most house plants, use light bulbs between 4000 and 6000 Kelvin, as the bulb's color temperature will borrow from a full spectrum of colors-cools and warms. With these lights, you can actually mimic the growth you would get in a greenhouse or outdoors.
Red is the main component that plants need for photosynthesis and stem elongation inhibition. Additionally, it signals to the plants that there are no other plants above it and that it can thus have uninhibited development.
Blue light is easier for a plant to absorb and use the energy in photosynthesis. So, blue light increases plant growth and makes the plant reach maturity faster. This is why blue light is especially important for seedlings and young plants.
