How long should I leave the straw net on my lawn?

Straw mat will naturally biodegrade. It has a Functional Longevity rating of 90 days. After that point, it will break down and be chopped up while mowing. We generally use it on sloped areas that may be susceptible to “wash-out” by rain. The net helps to hold the young blades of grass in place while its root system develops into an interlocking mat. The straw component acts as a mulch to keep the soil moist. Removing the straw mat too early can potentially remove all of your new grass with it.