The red mulberry tree is native to North America and is sometimes called the American mulberry. This tree is considered a small to medium-sized tree, growing to 50 or 60 feet tall with a spread of 25 to 35 feet. The surface roots are large and can lift or even break the concrete of driveways and sidewalks. The mulberries produced are a deep red to purple and attract birds and deer. Red mulberry is hardy to USDA planting zone 5.
Stake young trees. The tops will grow much quicker than the root system, and the trees will be easily blown over by strong winds. Use a cotton string or 8-inch strips of fabric and tie them loosely so as not to damage the bark.
Water the tree to keep the soil moist for the first two weeks after planting. Afterward, water twice a week through the first growing season. Once the tree is established, it will only need to be watered when the weather is particularly hot and dry.
Apply a time-release, general purpose fertilizer around the tree each spring. Water the fertilizer into the soil and keep it from touching the trunk of the tree. Follow the manufacturer's directions for the amount to apply per the size of the tree.
Place a 2-inch layer of compost on top of the soil over the roots each summer. Water the compost into the soil. This will help keep the soil draining well and improve the root system.
Prune the tree in January. Young mulberry trees may grow long branches that will droop from their own weight. These branches should be cut back by about a third to give the tree a nice shape. Trim off low branches every year, and cut all dead or damaged branches back to the main trunk.
Hand-pick weeds in a 3-foot diameter around the tree during the first growing season. In mid-fall, spread a 4-inch thick layer of mulch around the tree to protect the roots in the winter. In the spring, remove the mulch that is within 6 inches of the trunk and leave the rest to conserve moisture and keep the weeds from growing.