The black locust tree or Robinia pseudoacacia also can be referred to as the yellow locust. It grows in many types of soil but prefers moist, rich soil such as limestone. Black locust trees grow fast and mature to a medium size, up to 80 feet in height with an average diameter of 2 to 3 feet. The blue-green leaves are easily recognizable because each typically has seven to 19 leaflets. The entire leaf is up to 1 foot long. Plant black locust trees for ornamental purposes in USDA Hardiness zones 4 to 9.
Choose a planting location that allows enough space to accommodate a mature black locust tree, which can spread 25 to 30 feet.
Plant the tree in a sunny location, as black locusts do not tolerate shade well.
Dig a hole that's three times as large as the diameter of the tree's nursery container to give the roots enough room to grow without crowding. Dig the hole the same depth as the container.
Scrape the edge of the shovel against the bottom of the hole to loosen the soil so the roots will have an easier time spreading.
Pour water in the bottom of the hole to moisten the soil down deep. Remove the black locust tree from its nursery container. Cut away the container with pruning shears or sharp knife if the roots are stuck in the pot.
Loosen the root mass by hand gently. Put the tree in the center of the hole and refill with soil. Tamp it down as you go to eliminate air pockets.
Water the black locust tree until the soil is moist. Water deeply once a week for the first two months of growth. Keep the soil moist but not soggy.
Pull sprouts from the ground to prevent new black locust trees from growing under the current one.