Core lawn aeration, completed in the spring or fall (or both, especially if revitalizing a stressed or sadly neglected lawn) is considered one of the best practices for maintaining healthy lawns as it promotes strong turf by reducing soil compaction and thatch. The practice of removing plugs of lawn (which are approximately 2.5+ inches long, .75 inches in diameter and spaced 2 inches apart) is done by a company using specialized equipment. It’s a simple, non-chemical, relatively inexpensive process which promotes healthy growth throughout the lawn.
The removal of plugs creates better air circulation below the soil line, reduces approximately 10% of the thatch layer and allows moisture and other nutrients to reach the root system more efficiently. These healthy roots create a thicker lawn, which is less susceptible to weeds and more heat tolerant. When the plugs are left on the lawn to disintegrate in a week or so, they redistribute nutrients into the turf. However, raking up the plugs for aesthetics is a personal preference and perfectly OK.
Judging by the number of flyers left on my porch, there are a proliferation of companies offering an alternative to core aeration called liquid aeration. According to two reputable companies I contacted, this product is popular because it does not deposit plugs and provides 100% coverage. Both companies indicated they use proprietary formulations, applied with a truck-mounted hose. The liquid solution breaks up compaction and thatch through the use of non-toxic ingredients, such as thatch eating microbes and surfactants which are wetting agents that increase the absorption of water to the roots. Treatment prices vary and can be more than the cost of core aeration.
Liquid aeration treatments are receiving anecdotal praise by homeowners and appear to be gaining in popularity. Colorado State University researchers note that application of wetting agents at the correct rate may improve moisture absorption. However, liquid aeration’s impact on soil compaction or overall lawn health has not been scientifically researched. Without evidence to support or negate liquid aeration’s effectiveness, CSU continues to recommend the practice of traditional core aeration.
Photo courtesy of Jodi Torpey
Written by Linda McDonnell, a Denver County Master Gardener