Planting trees on slopes will be tricky, because dirt gets shaky when it is disturbed by running water, wind and gravity. Each of the plants, such as trees, onto a slope the ground in place. Preparing the site for tree setup makes it easier for the tree to set up its roots. It’s best to create flat terraces for trees at the planting location. The hardiest trees to plant on slopes endure harsh conditions while holding the soil in place.
Conifers can grow huge, but massive trees aren’t acceptable for slopes. When the soil becomes waterlogged, the tree may slip down the hill. The best conifers for hillside planting remain smaller and produce a network of roots. A more compact conifer, the “Blue Point” juniper (Juniperus chinensis “Blue Point”), grows well in U.S. Department of Agriculture plant hardiness zones 4 through 9. Bluish evergreen needles cover this 12-foot-tall pyramid-shaped tree. “Blue Pyramid” cypress (Cupressus arizonica “Blue Pyramid”) forms a pyramid as well, with compact divisions and blue-gray needles, growing in USDA zones 6 through 9. This North American native tree attains 20 to 25 feet tall and 10 to 12 feet broad.
Deciduous trees tend to grow quickly and produce tangles of roots. A couple of the hardiest trees to get slopes are “Kilmarnock” willow (Salix caprea “Kilmarnock”) along with also the red maple (Acer rubrum). The “Kilmarnock” willow creates a umbrella shape secured in yellowish pussy willow buds in the early spring. In USDA zones 4 through 8, this tree reaches 8 feet tall and 6 feet wide. The crimson maple grows best in USDA zones 3 through 9, producing lobed leaves that are green at the top and gray-white beneath. The leaves turn bright red in fall with this 30-foot-tall tree.
Evergreen trees keep their leaves year round, providing color and coverage to get the hillside. Ovens wattle (Acacia pravissima), in USDA plant hardiness zones 8 through 11, grows blue-green leaves and yellowish honey-scented blossoms in the late winter. This Australian native tree attains 20 feet tall with graceful weeping branches. Thornless Chilean mesquite (Prosopis chilensis) rises an open layer, which creates filtered shade under the canopy. The stems appear purple when initial growing in. This tree reaches 30 feet tall and broad in USDA zones 8 through 11.
Flowering trees generate a bright splash of colour on the hillside. One beautiful tree, the “Autumn Brilliance” apple serviceberry (Amelanchier x grandiflora “Autumn Brilliance”), has deciduous green leaves and clusters of aromatic white spring flowers. Small purple black fruit outlines the fading flowers, and the leaves turn orange-red during the autumn in USDA zones 4 through 9. This bird-attracting North American indigenous tree attains 20 to 25 feet tall and wide. “Spring Snow” crabapple (Malus x “Spring Snow”) grows best in USDA zones 4 through 8 with masses of white spring flowers appearing before the leaves form with this 25-foot-tall tree. This deciduous flowering tree does not produce fruit.