Native to northern climates in Asia, crab apple trees are adapted to and thrive in cold weather, and they require only full sun and well-drained soil to grow well. Although these trees require some water, they can survive with little water during dry weather. Depending on their size, they can reach up to 25 feet tall, and they produce showy orange or pink blossoms.
Because crab apple trees can grow up to 25 feet tall, plant them in a location where they have room to spread out and grow as well as have access to full sun. Since they thrive in well-drained soil, amend less than ideal soil with sand or compost to increase the drainage. Additionally, using compost adds nutrients to the soil. If the tree doesn't grow more than 5 inches per year, dress the soil with organic matter or a high-nitrogen fertilizer to increase soil richness.
After planting the tree, add 2 inches of mulch, and give it 1 inch of water each week until it's established. After it matures, it needs watering only during drought conditions. Regularly snip off any watersprouts and suckers, and remove any damaged, diseased or dead limbs. Keep an eye out for apple scab or frog-eye leaf spot, which are two fungal diseases common to crab apple trees.