Wisconsin is home to a wide variety of flowering trees, so choosing the ones best for your growing situation requires planning. Size, soil and light preferences all make a difference. Look for trees that provide garden appeal or privacy when not in bloom. Fragrant flowers, interesting foliage that changes color over the seasons, edible fruit and attractive bark will make your landscape interesting all year long.
Allegheny serviceberry (Amelanchier arborea) provides yearlong garden interest and grows wild in Wisconsin's cool woodlands and thickets as well as along swamp edges. Native Americans mixed the tree's dried summer berries with animal meat and fat to make pemmican cakes, a winter dietary staple. Fresh deep-purple berries are juicy, sweet and excellent sources of copper and iron. They are popular in preserves and pies. Birds flock to them.
Bronze-hued leaves arrive in May, become blue-green in summer and turn orange or red in fall. The tree's white-striped gray bark creates winter appeal. Its stature makes Allegheny serviceberry a good choice for small yards. The trees thrive in medium to coarse loam soil on the slightly dry side. Plant them from seed or buy young trees from nurseries.
Another flowering tree that works well in small spaces, the pawpaw (Asimina triloba) seldom grows taller than 20 feet. Smaller specimens of this tree, with their thick green tropical-like leaves tree, make interesting hedges. Pawpaw produces cupped, six-petaled, deep purple blooms followed by yellow-green oblong summer fruit. Ripening in the fall, pawpaw fruit has custard-like banana flavored pulp. It's edible raw, as an ice cream ingredient or as cooked pie filling.
These trees grow best in sun or part shade. They prefer moist, acidic soil high in organic content. One tree makes a good addition to a small garden, but planting two will permit cross-pollination and fruiting. Uncollected fruit can create a mess on lawns, sidewalks and driveways.
Leave the fruit outdoors to ripen, cautions the Lady Bird Johnson Wildflower Center, because of its overpowering smell. Some people develop indigestion from eating the fruit or mild dermatitis from handling either the leaves or fruit.
While black locust trees (Obinia pseudoacacia)) can reach more than 70 feet in height, trees between 30 and 50 feet are far more common. Recognizable for its crooked, spiny branches, black locust has dark bark and lacy blue-green foliage. Fragrant clusters of drooping white blossoms attract bees and hummingbirds during April and May.
Its tolerance of the poorest soils makes this tree very useful for land reclamation. The downside of its adaptability is that black locust is exceptionally invasive. Trees produce huge numbers of seeds. They also spread by sending out root sprouts. Their thorns and tough wood discourage pruning or removal. Look elsewhere for ornamental landscape trees.
For privacy screens and erosion control, black locust is a good choice. Plant trees in full sun and average well-drained soil. While black locusts can grow in almost any soil type, they do best in moist rich loam.