Are spike aerators as effective as core aerators?

Spike aerators create temporary holes in the soil by pushing solid tines into it. Still, they also compact the soil by forcing it sideways around the individual spikes. This process produces some short-term improvement but causes long-term increases in the density of the subsoil. Core aerators remove small, cylindrical core plugs of soil and create permanent holes or channels in the ground, approximately 10 to 15 cm in depth, allowing for the easy movement of air, water, and nutrients in the upper soil. This basic difference makes core aeration far superior for the maintenance of a healthy lawn.

The physics of soil displacement explains why spike aerators fail. A solid spike pushes soil particles to the side horizontally, compacting and forming denser areas. A hardpan is formed, which restricts root growth and the passage of moisture. Core aerators eliminate this problem by taking up soil cores themselves, forming open channels that will not corrode. In clay soils, the extraction of cores increased water entry through the soil by some 300%. At the same time, spike aeration showed negligible long-term benefits.

Root growth is another key difference. When core aeration holes are created, roots are able to penetrate down to depths of 10-15 cm in a matter of weeks to access subsurface moisture. These spike-created holes will collapse rapidly and force the roots to remain shallow, making them much more susceptible to drought. It is the difference in depth that affects drought tolerance directly: for example, lawns that receive core aeration will survive 50% longer without water in summer heat stress situations when compared to those that are simply spiked.

Although initially more expensive to use, core aeration is in the long run more cost-efficient. Lawns require yearly spiking versus biennial core aeration to achieve the same results regarding compaction control. Hence, the lifespan of the core created channels produces less need for maintenance, with the final results being superior. Homeowners receive better results by renting core aeration equipment than by buying inexpensive spiking tools, which supply only cosmetic improvement.

For strictly compacted or clay soils only, core aeration is the only successful remedy. Mechanical removal of the soil addresses compaction at its source, rather than displacing it. When overseeded, it will maximize utilization of the channels for quickened recovery of the turf. It is a process that makes an ailing lawn a hardy, low-maintenance plant in one growing season.

Read the full article: 10 Benefits of Lawn Aeration Explained