Coulter Lewis got the idea for Sunday when he saw the state of his local Home Depot's lawn care aisle.

"You can smell it before you get there," Lewis said on the Modern Retail Podcast. "It's pallets stacked high with bags of chemical fertilizer, covered in caution labels."

That was in 2017, the year before he launched the company out of Boulder, Colorado. First, Sunday asks customers to ship it a bit of soil from their property. Then it analyzes that alongside pre-existing soil and weather data before sending a regimen of pesticide-free products for you to apply via pouches that attach to your hose.

Customers pay on a subscription basis annually, receiving four boxes a year. Plot by plot, the company is hoping to eat big retailers' lunch; the outdoor lawn and garden sector brings in $13 billion in retail sales for Home Depot and Lowe's, Lewis said, and the grand total is more than thrice that).

"We're really not about coastal millennials. That's not our focus at all," Lewis said. "We're appealing to a more mass market."