There are many different types of plastic mulch available. The most widely used is black mulch because it prevents weed growth while keeping fairly high ground temperatures. Clear plastic, which is used for tunneling, also can be used on the ground. It provides higher ground temperatures than the black, but also allows for weeds to grow. Technology has now produce a greenish colored mulch known as IRT (infrared transmittant) which allows more light to reach the soil providing greater soil temperatures than that under black plastic, but not allowing weeds to grow like under clear plastic.
White plastic mulch is often used under tunnels in warmer climates because it keeps the soil and surrounding air cooler than any other colors of plastic. Other new types of plastic mulches showing promise are Coextruded silver on black, which is silver on one side, and black on the other. This plastic has shown increase in yields of some crops by radiating much heat and light to the plants canopy.