Create a warm, humid environment for your spring, fall and winter gardens. The DeWitt solar heating GRO-TUNNEL is constructed of DeWitt fleece cover which absorbs the heat of the sun while allowing air, water and light through to stimulate growth. The GRO-TUNNEL has two solar heated water tubes that run along each side. Each tube holds 10 gal of water, when heated will release BTUs of heat at night. The floor of the GRO-TUNNEL is made from DeWitt weed barrier landscape fabric, which collects heat, prevents weed growth and conserves soil moisture, in turn promoting healthy plant growth, thus eliminating the need for herbicides. When plant maturity has been reached, you simply slide the sides of the GRO-TUNNEL upward and harvest your crop.