The Importance of Core Aeration for a Healthier Lawn
What is aeration?
Technically speaking, aeration is the naturally occurring process of air exchange between the soil and its surrounding atmosphere. Practically speaking, aeration is the process of mechanically removing small plugs of thatch and soil from the lawn to improve natural soil aeration. It is commonly called “core aeration” in the lawn service industry.
What are the benefits of aeration?
Core aeration can help make your lawn healthier and reduce its maintenance requirements through these means:
- Improved air exchange between the soil and the atmosphere
- Enhanced soil water uptake
- Improved fertilizer uptake and use
- Reduced water runoff and puddling
- Stronger turfgrass roots
- Reduced soil compaction
- Enhanced heat and drought stress tolerance
- Improved resiliency and cushioning
- Enhanced thatch breakdown
Equipment affects the outcome
The type of aeration equipment can determine how effective the treatment will be. In general, turf responds best when core holes are close and deep. Equipment with hollow tines removes soil cores. Equipment with open tines divots the soil surface. Aeration equipment also varies in tine size up to 3/4 inch diameter and in depth of penetration up to 4 inches, depending on the manufacturer’s specifications.
SOIL compaction Turf grass in compacted soil (Left) grows slowly, lacks vigor and becomes thin or does not grow at alt Core aeration (center) removes small cores of soil, depositing them on the surface of the turf. This improves the depth and extent of turf grass rooting (right), and it can help save money on your raster bill.
Why's aeration necessary?
In most home lawns, fertile topsoil may have been removed or buried during excavation of the basement or footings, forcing grass to grow in subsoil that is more compact, higher in clay content and less likely to sustain a healthy lawn. Walking, playing and mowing will compact soil and stress lawns. Raindrops and irrigation further compact the soil, reducing large air spaces where roots readily grow. Compaction is greater on heavy clay soils than on sandy soils, and it is greatest in the upper 1 to 1 1/2 inches of soil. Aeration can help relieve soil compaction, allowing your grass to grow deeper roots and make better use of water and fertilizer.
How often should lawns be aerated?
Most lawns benefit from annual aeration. Heavily used lawns, or those growing on heavy clay or sub soils may need more than one aeration each year. Again, turf responds best when tine spacing is closer and penetration is deeper.
Relieve thatch accumulation
Most home lawns are subject to thatch accumulation. Left unmanaged, it impedes water, fertilizer and pesticide effectiveness. Core aeration combines soil with the thatch debris, so soil organisms are better able to break down the thatch and reduce its accumulation.
When is the best time to aerate?
If you have cool season turf grass such as Kentucky bluegrass and perennial rye grass, both spring and fall are ideal times to aerate. In spring, aerate between March and May. Perform fall aeration between August and November. Aeration before or at the time of late season fertilization enhances root growth and improves spring green-up and growth.
If you have cool season turf grass such as Kentucky bluegrass and perennial rye grass, both spring and fall are ideal times to aerate. In spring, aerate between March and May. Perform fall aeration between August and November. Aeration before or at the time of late season fertilization enhances root growth and improves spring green-up and growth.
THATCH BUILDUP-Although a thin layer of thatch is beneficial, thatch accumulation should not exceed 1/2 Inch. Excess thatch blocks out air, light and water from reaching root zones. Core aeration reduces thatch accumulation and minimizes its buildup.
What can you expect?
Immediately after aeration, your lawn will be dotted with small plugs pulled from the soil. All within a week or two, they break apart and disappear into tile lawn. About 7 to 10 days after aeration, the aeration holes will be filled with white, actively growing roots. This is a sign that the turf grass is receiving additional oxygen, moisture and nutrients from the soil.
On compacted soils and on lawns with slopes, you should see an immediate difference in water puddling and runoff after irrigation or rainfall. After aeration, your lawn should be able to go longer between waterings, without showing signs of wilt. With repeat aerations over time, your lawn will show enhanced heat and drought stress tolerance. Remember, most lawns benefit from annual aeration. And while you shouldn’t expect miracles, especially with poor soil, lawns that receive this care will be healthier, more vigorous and easier to maintain and have fewer pest problems.