Crabapple trees are widely planted as ornamentals in urban areas. They only grow to heights of 12 to 15 feet so they make excellent trees for city lots. Depending on the variety, they produce white, pink or dark pink blossoms in spring. In fall, they produce fruits ranging from marble size to golf-ball size. The fruits make excellent jelly. Some varieties hold onto their fruit all winter, providing food for birds.
Choose a site for your crabapple that gets 8 to 12 hours of sun a day. The soil can be sandy or clay but must be well-drained. Crabapple trees will not survive in soil that stays wet and saturated after rainfall.
Plant bare-root crabapple trees in early spring; they will not do well if planted after hot weather arrives. Crabapple trees in containers or with their roots balled and wrapped in burlap can be planted any time during the growing season up to three weeks before frost is expected in autumn.
Prepare the planting hole. Dig a hole that is twice as large as the root ball. Use a garden fork to loosen the soil at the bottom of the hole. Add a half cup of granulated slow-release fertilizer to the bottom of the hole and scratch it in with your garden fork.
Mix the soil that you removed from the hole with two 5-gallon buckets of peat moss and one 5-gallon bucket of compost.
Add some of the improved soil to the bottom of the hole. Set the crabapple in the hole. Add or subtract soil from beneath the root ball so that the tree will be growing at the same level as it was before planting in the ground. This is easy to determine because the bark on the stem will be slightly darker where it was buried.
Add a few shovelfuls of soil to the hole and gently firm with your foot. Do not compress the soil.
Fill the partially filled planting hole with water. Allow it to drain and then repeat. This helps settle the soil and insures that there are no air holes around the roots.
Fill the hole the rest of the way with the improved soil. Firm the surface with your foot, pressing down firmly, but do not overly compress the soil.
Use your hands to form a ridge around the perimeter of the planting hole. This creates a saucer around the tree and helps catch water.
Place a hose set to a slow trickle near the trunk of the tree. Leave it there for 30 to 60 minutes to thoroughly water the newly planted crabapple.
Mulch the area around the tree with 4 to 6 inches of straw, hay, wood chips or shredded bark.
During the first year of life after planting, provide the crabapple tree with the equivalent of 1 inch of rainfall per week. In subsequent years, it will survive without artificial watering except in times of extreme drought.