Harmelin Media, founded by CEO Joanne Harmelin in 1982, has grown to more than 220 employees and $600 million in billings. The Philadelphia-based media planning and buying company, whose clients include Ford, Blue Diamond Growers, Wawa, Pep Boys, Hostess and Hess, prides itself on relationship building. “Our key point of differentiation early on was customer care, which has helped us form long-lasting relationships, both with our clients and our personnel,” said Scott Davis, Harmelin’s evp, digital and technology. That philosophy has helped the agency make Blue Diamond Growers’ Almond Breeze, a client since 2010, the No. 1 selling almond milk in the U.S., surpassing Silk, in the last six months. “Even though we’re 35 years old, our entrepreneurial feel makes us seem like a startup,” said Mary Meder, Harmelin’s president.…