Spread along the banks of north central Pennsylvania's Lehigh River, Bethlehem was once one of the world's great steel-manufacturing cities. Its hot, humid summers and long, cold winters can make gardening a challenge. Maximize your chances of success by choosing plants and flowers--whether trees, shrubs, vines or grasses--adapted to the Lehigh Valley's soils and to surviving winters in US Hardiness Zone 6, where temperatures can fall as low as minus 10F.
While the red maple tree (Acer rubrum) seldom exceeds 60 feet in home landscapes, it can reach double that height in the wild. A red maple will bring three seasons of color to your Bethlehem garden. Male trees have interesting reddish-pink flowers in the early spring, while females produce red samaras (winged seedpods) just a bit later. The trees are at their ornamental best, however, with autumn displays of yellow to brilliant red leaves. Their silvery bark enhances the winter landscape.
Red maple likes moist, slightly acidic, well-drained soil and a sunny to partly shady location. According to the Lady Bird Johnson Wildflower Center, because their fibrous root mats are close to the soil's surface, other plants may not grow well around them.
Adding perennial butterfly weed (Asclepias tuberosa) to your Bethlehem garden will provide a long (May to September) season of brilliant butterfly-attracting yellow to orange color. A bushy plant standing 18 inches high, butterfly weed has deep green leaves that make its flat flowers clusters even more noticeable by contrast. The blooms make eye-catching additions to floral arrangements, especially those with yellow and blue flowers.
Butterfly weed does well in moderately dry conditions and sun to part shade. It tolerates all soils from sand to clay, but it does best in well-drained sand. Plants attract aphids as well as butterflies. Regular spraying with a soap and water solution will control aphid infestations.
Trumpet creeper (Campsis radican) is an aggressively growing vine that can reach up to 35 feet. Its dark green, oval-shaped leaves contrast effectively with the 3-to-4-inch orange or red-orange trumpet-like blossoms for which it's named. The flowers, growing in clusters at the end of the vine's branches, bloom all summer. Trumpet Creeper also produces 6-inch brown seedpods.
Trumpet creeper is as appealing to hummingbirds as butterfly weed is to Monarchs. Its aerial suckers let it climb any nearby support. Plant it where you can easily trim back excessive growth that might otherwise cause damage. Full sun maximizes flower production. Trumpet creeper thrives in any well-drained pH-neutral soil.