By the National Association of Landscape Professionals
Why does my lawn need aeration?
Over time, your lawn can become compacted by the pounding of heavy rains and by simply walking on it. The compacted surface inhibits water, nutrients, and air from reaching the plant’s root system.
Photograph courtesy of Hoffman Landscapes, Wilton, CT.
When is the best time to aerate?
Aeration can be done anytime during the growing season. How many times your lawn needs aerating depends on its soil compaction. The two most popular times to aerate are in spring and fall. Spring aeration gives grass plants a little extra boost and provides faster greening; fall aeration helps strengthen underground root systems while providing an excellent bed for overseeding. Your landscape professional can tell if your lawn needs aerating and suggest the most appropriate time to have it done.
How does an aerator work?
There are several types of pull and walk-behind aerators on the market. The most common is a core-type unit that removes small plugs from the turf. Core aerators have a minimum penetration of 2 ½ inches and remove plugs anywhere from ¼ to ¾ inches in diameter. Spiking units push small tines into the turf without removing soil plugs. A third type, slicing aerators, literally slice through the soil creating openings.
What are some immediate and long-term benefits?
Aeration immediately opens up the soil to air, water, and nutrients. The openings allow air penetration and better water movement, and give plant roots a place to stretch out and grow to become more vigorous and dense.
Over time, aerated lawns are less susceptible to disease and thatch buildup. In some cases, the process can even solve small thatch problems. In addition, aeration reduces water runoff and increases turf tolerance to heat and drought.
Aeration is a natural process that has no ill side effects. Even the small plugs left behind by core-type aerators are beneficial. In the process of breaking down, they deposit a light coating of top dressing that helps decompose thatch accumulated at the base of grass plants.