Guest post by Alisa Bryce
Water repellence is when water can’t filter into a soil. Instead it pools on top and often runs off, sometimes causing erosion.
Water repellent soil (or hydrophobic soil) develops for two main reasons.
- When the soil has remained dry for a prolonged period
- The soil particles become covered with a waxy coating
Fresh compost and mulches are a frequent source of waxy coatings. This is why it’s important to use aged compost and mulch.
In Australia, overhanging eucalyptus trees are another common culprit of water repellence. As the leaves decompose, the eucalyptus oil inside is released and coats soil particles.