Improving Your Soil

Ed Murtagh - November 26, 2012
If we ever want to see cool, clean water flowing through Sligo Creek, we will have to stop treating our soil like dirt.

Unfortunately, much of the soil in the Sligo watershed is degraded. Years ago Franklin D. Roosevelt noted that “the Nation that destroys its soil destroys itself.” This is as much applicable today as it was 70 years ago. The government alone cannot solve this problem. Many, many property owners will need to improve their soils before we will see healthy watershed and clean water in our streams and rivers.

Why is improving soil so important? Improving your soil will help increase water retention and penetration, improve drainage, and remove potential pollutants. Rainwater, instead of rushing hot and polluted into Sligo Creek, needs to soak slowly into healthy soils where it will be cooled and cleansed.

Healthy soil is alive with microorganisms. A teaspoonful of healthy soil contains billions (yes, billions) of beneficial organisms! These organisms naturally metabolize many pollutants, producing byproducts that are less toxic than the original chemicals. The good news for homeowners is that improving your soil is not toodifficult if you gradually improve your lawn by sections and from time to time. Watch where stormwater runoff flows from your roof, patio, porch, and other hard surfaces; target first the soil in those areas where this stormwater flows.

Healthy soil needs a good balance of air (pore space) for water and air, organics, and nutrients. Compacted soil does not have enough pore space to grow healthy vegetation and allow rainwater to soak into the ground.

To improve your soil, the Environmental Protection Agency’s GreenScapes webpage recommends digging (or rototilling) one to three inches of compost (such as decayed or shredded leaf litter) into 6 to 12 inches of top soil. Compost helps sandy soils hold nutrients and water, loosens clay soils, and feeds the beneficial soil organisms so the soil can, in turn, feed and protect your plants.

To improve an area of your lawn, you need to first remove the grass. We have found that a sod-cutter works well. Not only does it remove the sod, but it leaves the sod in strips that can be used to re-sod the ground or used elsewhere in your yard if you are going to create a garden in your newly improved soil.

What is compost? It can be shredded leaves and other organic matter, brimming with healthy bacteria and fungi such as mycorrhyzae that help plant roots absorb and process water, gases, and other nutrients. You can help our local municipal recycling programs by using city compost from Takoma Park and College Park.

Leafgro, which is made from leaves and grass clippings from Montgomery and Prince George’s counties, is also a great local source of compost. The “greenest” source of compost is from your own yard.

For more information about improving your soil with compost and other techniques, see my blog about conservation landscaping For information about RainScapes and the County rebate program, go to

To keep soil healthy, try to prevent compression by walking on pavers instead of on the soil and not parking heavy equipment on the soil. Planting native plants with deep roots in the soil will help maintain your good soil structure.

I will close this blog with this useful hint: a cubic yard of compost will provide three inches of compost for just over 100 square feet of yard.

Interested in learning more? Visit Friends of Sligo Creeks website and get on our email list, or follow us on Facebook.

About the author:
Ed Murtagh is the Chair of the FoSC Stormwater Committee and a board member of GreenWheaton.