Pine Straw Mulch - Pine Needle Mulch - Free Shipping - 200SqFt - 9 Inch Pine Mulch Pine Straw Mulch - Pine Needle Mulch - 200 Square Feet Coverage at a 2 - 3 inch depth. Standard Pine Straw has a pine needle length of 9 inches. Great for flower beds, garden areas, and can be an effective method of weed control. Pine straw helps insulate the soil from temperature fluctuations and will not move with heavy rains. A wide variety of plants thrive with pine straw mulch, including azaleas, camellias, hostas, ferns, hydrangea, magnolias.