As the definition describes, mulch is perfect for protecting your plants roots, especially from drought, heat or cold. It provides a natural, recyclable barrier that "insulates" your plants roots from the external conditions.
All mulches will let water drain through from above but slow the movement back up through evaporation. This is even true of any irrigation you may apply to your borders.
There are 2 sizes available:
Click on the photo below to see more information:
Sample work with Bark Mulch: