How to Prevent Root Rot Using Expanded Clay


The fungus that causes root rot thrives in soil that is water-logged and over-watered. The best way to protect your plants is to plant them in well-drained soil. However, not every garden offers that option. Fortunately, root rot can be prevented even in poorly-drained soils by using expanded clay. Also known as fired clay pebbles or grow rocks, this porous soil amendment maximizes drainage to prevent the growth of root rot.

Step 1

Dig your planting hole(s) 4 inches deeper than they need to be to amend them with expanded clay. For example, if you are planting container plants, dig the hole a little wider than the container, but 4 inches deeper. Line the bottom of the each hole with 3 inches of expanded clay. Cover the expanded clay with 1 inch of the excavated soil.

Step 2

Till large planting areas to a depth of 4 inches with a rototiller or hand tiller to amend with expanded clay. Spread 5 inches of expanded clay onto the top of the soil. Till the soil again to a depth of 6 inches.

Step 3

Plant as usual and water the soil until it is thoroughly moist.

Things You'll Need

  • Shovel
  • Trowel


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Keywords: prevent root rot, expanded clay, plant clay

About this Author

Emma Gin is a freelance writer who specializes in green, healthy and smart living. She is currently working on developing a weight-loss website that focuses on community and re-education. Gin is also working on a collection of short stories, because she knows what they say about idle hands.