Turf Tips

Spring Lawn Aerification

Aerification, sometimes called core cultivation is a supplementary lawn cultural practice primarily used to relieve soil compaction and remove thatch (the spongy layer of undecomposed stems at the soil surface). This practices is not necessarily essential to maintaining a lawn, however, it can be very beneficial to most turf areas. In addition, to the aforementioned benefits, creating aerification holes promotes water infiltration, improves soil oxygen diffusion and provides channels which promote deeper turfgrass rooting.

Frequently asked questions:

When should this practice be conducted?
Aerification can be conducted anytime the turf is healthy enough to recover and grow back. For cool-season grasses like the bluegrass, ryegrass and fescues, it is generally best conducted during the spring and fall months. From a practical stand-point on non-irrigated sites, spring aerification may be more effective than late-summer or fall simply because the soil is simply more moist which enables the aerification equipment to remove a deeper plug. Be careful, however, on excessively wet sites as the tines on the machine may simply become plugged with soil and the full benefits of core removal will not be realized.

How many holes should I create?
For recreational or athletic turf areas the rule of thumb has historically been that a truly effective program should impact and remove at least 20% of the entire surface annually. Thus, fully affecting the entire turf area once every 5 years. The tine size and tine spacing of each piece of equipment will affect how many passes across the turf is actually required. In practice this 20% rule is achievable for recreational turf areas but in lawn turf is much more difficult simply due to equipment limitations. Regardless, more holes is better and one hole per square foot is probably not enough.

Plugs, what to do with them?

Generally it is easiest to simply leave them on the turf surface and allow regular mowing and rain dissolve them back into the turf.  

What about spring aerification and pre-emergence herbicides?
In general, it is best to aerify prior to applying your spring pre-emergent weed and feed products. The reason being is that for pre-emergents to be effective there must be a continuous herbicide barrier in the soil. Anything that disturbs or “breaks” the barrier may result in poor control or “break-through”.

Cale Bigelow, Assistant Professor of Turfgrass Science

Send corrections, suggestions, and comments to biehlj@purdue.edu