She recently trimmed the boxwood border along both sides of her clematis pergola. Credit: Courtesy of The Martha BlogRight now, during late summer, is one of the busiest times on Martha’s Bedford farm. Her gardeners and outdoor grounds crew are hard at work keeping up with the season’s abundant growth, including the many boxwood shrubs.In a recent blog post, Martha shares that she has “hundreds of these handsome evergreen shrubs across the prope…