There is scientific research being evaluated with respect to warm whites and some people believe that warm whites are better for flowering plants while cool whites are more suitable for green, leafy growth. It is said, when used together, these bulbs are close to the full spectrum light that comes from the sun, but nothing matches the sun, nor is the combination true to the measure of full spectrum LED grow lighting. Light Emitting Diode grow lights produce a photosynthetic optimum red (640-680 nm) and blue (430-460nm) and they have long life expediencies, and efficiency. One can extend their understanding of light with the measures of photons outside the ranges of 400-700nm. When we look at 360-740nm (ultraviolet through near infra-red) you begin to see that certain plants do use light outside of PAR, such as far-red light above 700nm which increases photosynthetic efficiency (this is called the Emerson effect) and also for hormone regulation.