Vertical Mulching

What is vertical mulching? Quick answer: Vertical mulching is a technique used to help alleviate soil compaction in the critical root zones of trees. Compacted soil can be detrimental to the tree’s health by reducing the amount of pore space that allows room for oxygen and water– both vital to the tree’s wellbeing.

The vertical mulching process requires use of a power auger, used to meticulously drill holes from a safe distance around the tree to its dripline. Extreme care must be taken to ensure no tree roots are harmed during this process. Then the holes are filled in with pea gravel, sand, or a compost mixture, depending on the soil type. This vertical mulching process, and the backfilling of drilled holes injects the soil with well-aerated pockets that are receptive to the infiltration of water and oxygen, leading to healthier tree roots and a happier tree. 

Fast Facts about Vertical Mulching:

  • Vertical mulching is a process that allows for the aeration of the soil surrounding a tree, making it more susceptible to the intake of water and oxygen.

  • Signs that your soil is compacted and needs vertical mulching are pooling or puddling water in lower areas, water running off the soil in high areas, areas too hard to drive a shovel into the soil, and bare areas where grass and weeds don’t grow.

  • The best time for soil aeration is the growing season, when grass can grow and heal, filling in open areas of ground.

  • Vertical mulching allows for increased oxygen levels, helps fertilize the soil, and can lessen damage from overwatering. It can also allow sub-soil water to reach the tree’s protection zone during dry periods of time.

Vertical Mulching