The magnolia, also referred to as Southern magnolia, is an evergreen tree native to North America. Magnolia trees are hardy in USDA growing zones 7 through 10A and desired for the large, fragrant flowers they produce. The tree grows to a height of 80 feet and spreads out to 40 feet, with the branches bending towards the ground. Magnolia trees are drought-resistant, but grow best when provided supplemental water during periods of dry weather.
Choose a magnolia tree planting area that has full sunlight and an acidic, well-draining soil. Make sure the area provides a wind block to prevent branch and trunk damage.
Test the planting location soil as the tree grows best in a pH of 5.5 to 6.0. Work ground rock sulfur into the soil to a depth of 6 to 8 inches to lower the pH number. Water the area well and let it rest a minimum of two weeks before planting the magnolia tree.
Plant the magnolia tree in a hole that is slightly deeper than and twice as wide as the root ball. Place 2 inches of organic compost into the bottom of the hole and set the root ball in so the top is at ground level. Work an even amount of organic compost into the removed soil and fill it around the root ball.
Water the magnolia during the first growing season with a deep application that moistens the soil to 8 to 10 inches once a week. Provide supplemental water to the magnolia tree during periods of drought when the soil dries to a depth of 3 to 4 inches.
Place a 3-inch layer of organic mulch around the tree, making sure to leave a 6-inch gap between the trunk of the tree and the start of the mulch. Refresh the mulch each spring to keep a consistent layer around the tree. Mulch assists with soil moisture retention and prevents weed growth that competes with the tree for moisture and nutrients.
Apply a water-soluble tree fertilizer over the root ball in spring and early fall. Apply a potash-based fertilizer to the soil over the root ball once the magnolia tree buds appear. Follow the fertilizer package instructions for the recommended amount based on the size of the tree.
Prune only to remove dead and damaged branches. Do not prune healthy limbs from established trees as the cut wounds do not heal quickly and create an environment for disease to enter the tree. Apply a tree wound paint to speed the healing process.