As the snow melts and lawns come out of winter dormancy, we need to look at the benefits of seed slicing versus aerating. In the spring, it’s common to thicken lawns through overseeding and reduce compaction through core aerating. Although aeration is a great practice, and should be regularly performed on residential lawns, it can create unanticipated problems when performed in the spring.
Core aeration pulls plugs of soil from below the turf grass crowns and deposits them above ground. This opens up space for air and water to enter the soil, and for turf grass roots to spread. As cores are brought to the surface, there’s risk that weed seeds are also brought to the surface and given a chance to germinate. These weed seeds would have otherwise remained buried and the existing turf cover would have kept them at bay. Due to this potential risk, core aeration should be avoided on lawns in the spring unless the area is so compacted that water can’t filtrate the soil profile.
A slice seeder (also known as a slit seeder) is a great alternative to core aeration for spring overseeding. These machines cut small slits into the soil, and then deposit grass seed into the cut rows. They provide great seed-to-soil contact to help with germination, minimize soil disruption, and reduce the risk of exposing weed seeds in your lawns. It’s important to note that seed slicing v aerating does not address compaction, and lawns should still be aerated and overseeded in the fall.
Ultimately, the goal of spring overseeding is to improve turf density and minimize weed pressure. The spring overseeding window to establish grass can be very short, so we recommend using a TriRye grass seed. TriRye grass seed is known for quick germination and should be put down before May 15th. Since it can take up to 18 months for grass to become fully established from seed, anticipate some die off from spring overseeding as you enter the heat of the summer.*
Spring is almost a week away, let’s make sure our lawns are ready for the warmer days ahead!
*Plan accordingly, and follow up with a second overseed in the fall. If your budget only allows for one overseed a season, wait until fall; Fall is the best window to focus on establishing grass from seed to thicken the lawn.