Hands holding compost

SOIL AMENDMENTS

What is a Soil Amendment?

A soil amendment is any material added to a soil to improve its physical properties, such as water retention, permeability, water infiltration, drainage, aeration, and structure. The goal is to provide a better environment for roots to grow. 

Transform your lawn into a stormwater sponge. Healthy lawns develop thick root systems that help absorb more rain, reducing water pollution and the amount of water that can get into sewers. Grass with thick root systems also becomes more drought-tolerant and outcompetes weeds. To improve the health of your lawn and help protect Lake Michigan, follow the five steps below.

Five Steps For a Healthier Grass

1. MOW OFTEN AND RECYCLE GRASS CLIPPINGS

Follow the 1/3 rule. When you mow, remove no more than 1/3 of the total height of the grass. Allowing the grass to stay tall encourages deeper root growth. Tall grass also helps keep weed seeds from germinating—especially crabgrass seeds that need light to germinate. Keeping the lawn tall throughout the summer will keep the surface of the soil from drying out and reduce the need for watering. 

Never bag your grass clippings and send them off to the dump or sweep into the street. Grass clippings contain valuable organic matter and nutrients that should be returned to your lawn and not end up in our waterways.

What aerating and adding soil amendment do to your lawn

2. DETHATCH, THEN AERATE

Thatch is a barrier of natural material that makes it difficult for water and nutrients to get to the soil. Dethatch with a stiff rake, collect the thatch and add it to your compost. Once your surface is ready, it's time to aerate. 

Aeration pulls cores of soil and grass from your lawn and leaves them on the surface. Aeration loosens compacted soil, improves drainage, encourages deep root growth, reduces weeds, decreases the need for fertilizer, and prevents thatch.

Aerate your lawn in early fall every other year; aerating in the spring can damage new grass shoots. Many hardware stores have aerators for rent, or you can call a local landscaping company to handle the job.

3. TOP-DRESS YOUR LAWN - ADD SOIL AMENDMENT 

After aerating your lawn, it's ideal to top-dress it with a thin layer of high-quality compost, topsoil, or manure. Regularly top-dressing your lawn by adding soil amendment improves drainage and drought resistance, reduces compaction, and helps build organic matter in the soil.

4. FEED YOUR LAWN

Select a slow-release fertilizer, like Milorganite® to provide a consistent nutrient source for grass. Slow-release fertilizer not only feeds your lawn, but increases beneficial soil microorganisms, won't burn, and improves the structure of your soil. 

In spring, fertilize your lawn with Milorganite after the last frost and once it begins to grow green. 

For the last application, fertilize with Milorganite as late in the season as possible—just before the first deep freeze or snowfall. This fertilizer application, known as “dormant feeding,” encourages healthier, greener lawn in spring.

5. OVERSEED YOUR LAWN

Overseeding is the planting of grass seed directly into existing grass, without tearing up the grass or soil. It's an easy way to fill in bare spots that weeds would otherwise take over, and improve the density of your grass, which leads to better water absorption.  Fall is the best time to overseed, but spring is acceptable if that's when you can get to it.