Specialized equipment can increase the effectiveness of certain lawn care practices and make the job much easier. Match equipment to the task that needs to be done for best results.
Core aerification is an important and highly recommended practice for many lawns. This process is used to reduce soil compaction and thatch, improve surface drainage, increase soil oxygen and improve conditions prior to overseeding. Core aerifiers insert hollow tines into the lawn and remove plugs of soil. Size of cores removed will depend on the machine used, soil moisture, and type of soil. Core spacing also varies with the specific machine being used. On average, holes should be 3-4 inches apart. Machines can be rented or aerifying services are available through lawn maintenance companies.
Core aerifying should be done when lawns are actively growing. Early to mid fall is an ideal time. Removing 15 to 20 cores per square foot of lawn is suggested; this usually requires more than one pass over the lawn. Make passes perpendicular to each other. Cores should remain on the surface and be allowed to air dry, later buffing the soil in and removing leftover debris. These cores act as topdressing which helps degrade thatch. Additional topdressing material could be added after core aerifying. This is especially important if overseeding is to be done. This is an excellent time to topdress with organic matter.
Spikers are similar to core aerifiers in that they make holes in the soil. However, they use solid tines, and thus, do not remove cores. Spikers can be effective on sandy soils where compaction is not as critical as on clay soils.
Vertical mowers have rotating blades arranged vertically that can cut into turf and soil. These machines can be used to remove thatch (dethatching). Turfgrass rooting in the thatch is typically torn out, so reseeding is suggested afterwards. Vertical mowers can also roughen bare soil prior to overseeding areas.
Slit-seeders are useful for lawn renovation projects. As the machine goes across the lawn, it opens the soil using a vertical disc and deposits seed directly into the soil opening. Most slit-seeders have a roller that helps firm the soil after seeding. Seed is metered at a predetermined rate; it's suggested to apply half the desired seeding rate in one direction and the other half on a second pass perpendicular to the first.
Since the seed is placed in direct contact with the soil, seeding success is usually high when using slit-seeders. In addition, existing grass and debris does not need to be completely removed prior to the overseeding process. Timing should be the same as for conventional lawn seeding, which ideally would be late August into early September. Many rental agencies carry slit-seeders or many lawn and landscape services offer this as one of their services.
When purchasing any of these services, clearly communicate what you want done. Make sure you understand what the company will do, all materials that will be used, and what the price will include.