Magnolia trees are native to both the eastern US and southeast Asia. Fairly easy to grow and not a big attractor of pests, magnolias are ideal plants for landscaping. The trees produce large green leaves and attractive flowers. While fertilization is not absolutely essential to the growth of a magnolia tree, properly fertilizing the plant will help it thrive.
Plant the magnolia tree into the native soil of the area and water the soil thoroughly. Cover the base of the trunk with 3 to 5 inches of mulch, but do not fertilize until the magnolia has established itself on the land.
Use an acidic liquid fertilizer on a magnolia tree every few months for the first 3 years of growth. In the first growing season, use 1 cup of fertilizer around the planting circumference of the planting hole in March, May and July.
Increase the amount of fertilizer to 2 cups in the second year. Start at the edges of the tree's canopy and spread the fertilizer outward to 3 feet beyond the canopy's edge in March, May and July.
Up the amount of fertilizer to 4 cups in year three. Spread the fertilizer from the canopy's edge outward 6 feet.
Place granular, slow-release fertilizer at the base of the magnolia tree a few times throughout the tree's growing season after the first 3 years. At this point, the magnolia tree should have established a wide root system and be able to find most of its own nourishment in the soil.