Keep SteadySpring Tree Mats in place for 1 year plus 1 year per inch of caliper (e.g. 2 years for 1inch caliper trees, 3 years for 2inch caliper trees) to ensure establishment of the trees in the environment. Rated life of SteadySpring Tree Mats is 3-5 years. Leave out year-round - even in frozen climates! They will refill themselves with snow and rain while protecting your plants against freezing temperatures and deicing salts! Cover with wood chips or coarse-structured mulch to help prevent direct sunlight exposure, while returning nutrients to tree roots, reducing evaporation, providing insulation to the root system, and keeping the SteadySpring mat from getting stolen! Do not use dirt/soil/fine sand/fine-structured mulch to cover SteadySpring Tree Mats because the small particles may block rainwater! Weed barrier on top suppresses weeds and other plant life from utilizing water your plants need. To Fully Charge, Soak for 1-3 hours, Water the plant once, and then Set it and Forget it for 30+ Days or more. SteadySpring saves you water, stress, and time, and frees you to travel without having to worry about your plants!Steady Spring has a weed barrier top to eliminate plants and weeds growing around the root system that normally steal water and nutrients. This allows for less water to be used. Colour:Black Material:PVC Package Contents: 4x Tree Watering Mat Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.