Every year when the Austin City Limits Festival returns, hundreds of thousands of people lay, walk and run on the grass at Zilker Park as they bounce between stages to see their favorite artists. All of that activity leaves the usually green lawn looking a bit brown and sad. But a team of experts help it bounce back.
Pablo Agustin Boeri, a turfgrass extension specialist with Texas A&M University, said the people, vehicles and stage equipment that go into building the music festival can alter the lawn and underlying soil, often resulting in long-term effects, like limited growth potential and soil erosion, that extend well beyond the duration of the event.
“That stress comes in two ways," Boeri said. "One is going to be wear. That is the direct damage to the turf canopy. And the other one is going to be soil compaction.”
Soil compaction is the soil being pushed down under the weight of foot traffic or heavy equipment. When soil is compacted, it reduces the space it needs to hold air, water and nutrients. That restricts the grass' roots ability to grow and slows the recovery of the grass.
But with the right approach before and after events, Boeri said turf can actually be pretty resilient.
"You achieve that by following best management practices for turf," he said. "Apply the right amount of fertilizers, the right amount of irrigation, and the correct timing for pesticides.”
In the weeks before ACL Fest, the city’s teams spend hundreds of hours preparing the lawn. That includes spreading dirt and fertilizer, and aerating and watering the lawn before it turns into the site of a music festival.
All those supplies and tools do come at a price. In 2024, more than $20,000 was spent on lawn care before and after the festival, according to city documents obtained by KUT News. The city pays for this up front, and then ACL Fest reimburses it for the materials and labor used to restore and maintain the grounds.
The Austin Parks Foundation also invests in the health of the park and the lawn. The organization maintains the parks and trails in Austin, and is a partner in putting on the festival. It has spent more than $6.8 million for maintenance at Zilker Park over the last 25 years to ensure the lawn is in the best shape for residents and festival goers, Colin Wallis, CEO of the Austin Parks Foundation said.
Wallis said there is an agreement in place for ACL Fest with the city to protect Zilker that involves remediating the property according to specifications provided by Austin Parks and Recreation, paying for any damages to property or plant life, protecting the park grounds and trees, and following a specific plan for crossing grass.
Merrideth Jiles, parks ground manager for Austin Parks and Recreation Department, is part of the turf team that focuses on the lawns at Zilker Park and Vic Mathias Shores Park. He said aeration is an important part of preparation.
The city uses a tractor to poke holes in the ground to loosen the soil and allow air and water to flow through it. But water and fertilizer are also key in toughening the grass and then helping it regrow.
"There is a perception of a lot of damage," Jiles said. "But really it is amazing how much of the turf just comes back... This is really tough grass.”
After the festival concludes each night, Jiles said teams go in and treat areas of the park that might be dry or need attention. The days in between the two weekends are also vital.
But it's the days after the festival that really help sustain the turf’s longevity.
Jiles said teams get to work after the festival ends and focus on irrigation as well as aerating and fertilizer the soil to get it healthy and back to a point where the grass can start to regrow.
This type of care doesn't just happen during the festival though, it continues year-round.
"It's not just events like this that have impacts to it but even just regular use," Jiles said. "Anytime there are people on the lawn doing things, it's going to impact a turf area. So our primary goal is really just to keep it as healthy as possible with these processes of aerating, irrigating and fertilizing.”
The lawn at Zilker Park will close from Oct. 20 to 31 for its annual fall maintenance.
