by Connie Oswald Stofko The established perennial garden in the front yard of 166 York St., Buffalo, was an added incentive for Nick and Marideth Heim to buy the home three years ago. That garden was one of more than 400 landscapes that were shared on Garden Walk Buffalo on July 25 and 26. Garden Walk Buffalo is the largest garden walk in the nation. Many of the streets were crowded with visitors, and free shuttles drove tourists among the…