Editor's Note: This article is part of a series that takes a closer look at select Inc. 5000 companies in the trenches.

In 2010, Paul Lightfoot left the software firm he co-owned in New York City to chase a verdant dream. He had adopted a healthy lifestyle focused on organic and sustainable food and knew that supermarket chains were clamoring for locally sourced greens. If they'd agree to forge long-term partnerships with Lightfoot, who had nearly a decade of supply-chain expertise under his belt, he could build local greenhouses to provide kale, spinach, romaine, and other salad greens. He launched BrightFarms in 2011 and opened a 56,000-square-foot greenhouse in Bucks County, Pennsylvania. Two years later, he added two more over twice that size, one near Chicago and another near D.C. (pictured). Soon, a fourth will open outside Cincinnati. These farms use advanced hydroponic systems to reduce water consumption and increase crop yield. BrightFarms' clients include Kroger, Acme, and ShopRite. "Initially, some chains were concerned about a long-term partnership," says Lightfoot, "but our greens have helped them both grow their salad category and attract younger, health-conscious customers." Here's how Lightfoot persuaded some of the country's biggest grocers to sign on to his big idea. --As told to Coeli Carr

To sell our produce, we didn't want to focus on food service, which is basically a hundred million targets; that makes it difficult to know where to start. We knew our chances of getting purchase commitments would be much better if we focused on supermarkets.

There were a few dozen of them we wanted to connect with--a big enough number to partner with and convince our investors, but also small enough so I could put a list of names on a wall. Too many options makes it impossible to work through, and too few means you can come up short. You need a good balance between fragmentation and concentration.

I had a team, but largely in the beginning, it was just me networking. We got into industry publications to make our target companies aware of us and to broadcast our concept in a cost-effective way. I'd attend trade shows that I knew key people would attend. I cold-called. I was really aggressive. I made a promising connection with a vice president at one of the country's largest supermarket chains, but then he went silent and stopped responding to my emails and phone calls. So I wrote a letter and faxed it to him.

In B2B, getting a retailer to buy a consumer product by analyzing its motivations and fears is an old-fashioned strategy that's not going to change. Low tech is a viable option.