Garden reflection

I am planning on setting up a small grow area and do not know what to use for reflecting the light back on the plants. I have considered both Mylar and black and white poly among other materials. Which one reflects more light, and how are they on retaining heat?

Both Mylar and black/white plastic reflect 80-90 percent of the light. Mylar reflects heat and infrared light back to the garden. The plastic absorbs the heat and some of the infrared light and then acts as a heat exchanger, heating the air and solid surfaces. Both materials will perform well for years. Black/white plastic is opaque. You can see bright lights through Mylar.

Mylar is far more expensive than polyethylene and harder to work with because it creases and stains. It is easiest to use when it is attached to a wall. When it is draped it often curls or tears from wear. It is best taped or reinforced with duct tape to prevent tearing.

Polyethylene is inexpensive, easy to use, cleans quickly using a sponge, detergent and water, and can be draped or attached to a frame to create a space. It can be taped or tacked to a wall and can be handled rather roughly.

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