Planting on Clay Soils
Here are a few tips to remember when planting on clay soil.
- Don’t expect water to infiltrate well in heavy clay soils.
- If you are unable to amend the soil, consider making the garden wider and shallower than recommended to increase the surface area for water infiltration.
- Follow the soil amendments guide at right to remove clay soil and improve infiltration.
- Dig the site and add compost to the soil. This will allow plants a habitat rich in nutrients and maximum capacity to soak up the rain and snow melt.
Adding Fresh Soil
When adding fresh soil, consider the following mixture:
- 50- 60% sand and gravel,
- 20-30% topsoil (no clay) and
- 10-20% compost and mulch
The clay-based rain garden at Superior Middle School (pictured above) was a swimming pool until we back-filled it with rocks, sand, peat, mulch, and compost. It still drains slowly, but doesn't fill up with rainwater as quickly as it did when it was first dug.