This tree is best planted in the spring. Trees in their first growing season will need regular watering, but after that you likely won’t have to worry about watering unless your climate is dry. The pruning and fertilization requirements for this native tree are also minimal.
Light
This tree can grow in full to partial sunlight. That means it should get at least four hours of direct sunlight on most days.
Soil
The black gum tree is tolerant of various soil types. It prefers loamy soil with an acidic pH and good drainage. But it can handle a spot with poor drainage and even some standing water. It is moderately tolerant of clay soil, as well as gravelly or sandy soil.
Water
The tree likes moist soil and should be watered regularly when it is young to maintain even soil moisture. However, it also has some drought tolerance, and mature trees can adapt to growing in relatively dry soils. Still, if you have a prolonged period without rainfall and your soil begins to dry out, you should water your tree.
Temperature and Humidity
Black gum trees grow naturally in a variety of climates and are hardy both to cold and to heat. Humidity usually isn’t an issue for the tree, as long as there is good air flow among its branches. Otherwise, high humidity and cramped branches can lead to fungal growth.
Fertilizer
Feed this tree annually in the fall using a slow-release granular fertilizer. In general, use 2 cups of fertilizer per every inch of trunk diameter, measuring the trunk at about 4 feet off the ground. Sprinkle the fertilizer into the soil around the tree in an area that extends 1.5 times the distance from the trunk to the tips of the branches.
Black Gum Tree Varieties
Varieties of the black gum tree include:
‘Zydeco Twist’: This variety features somewhat twisting branches, which really stand out during the winter months when the tree is bare.‘Autumn Cascades’: This weeping variety is known for its especially attractive yellow, orange, and red fall foliage.‘Wildfire’: This tree will produce red leaves throughout the growing season.‘Firestarter’: A trademarked cultivar with early, vivid red fall coloring, this variety does not produce fruit.‘Tupelo Tower’: This tree has a somewhat columnar growth habit and turns to shades of gold, amber, and scarlet in the fall.
Pruning
Black gum tree doesn’t require much pruning beyond trimming branches to retain your desired shape and removing any parts that are damaged, diseased, or dead. If any of the lower branches are drooping downward, you can prune those off if you wish to make walking around the tree easier. The best time for general pruning is in the late fall or the late winter after the coldest weather has passed, though you can cut out problematic branches at any point.
Propagating Black Gum Tree
Propagating black gum tree from cuttings is difficult. Growing it from the seed yields unpredictable results—you won’t necessarily get the same attractive fall color that you admire in the parent tree. In addition, the propagation of trademarked cultivars is prohibited. Therefore, if you want to plant a black gum tree, it is recommended to source it from a nursery.
Potting and Repotting Black Gum Tree
Black gum tree is a large landscape tree with a long tap root that is not suitable for container growing.
Overwintering
The tree is hardy to USDA zone 3 and does not require winter protection.
Common Pests and Plant Diseases
Black gum tree typically doesn’t have any serious issues with pests or diseases. Keep an eye out for leaf spots, cankers, leaf miners, and scale. Look for discolored or damaged foliage, as well as abnormal-looking bark and branches.