A tree fern is a large fern that can reach a whopping height of 15 to 30 feet with fronds between 1 and 1½ feet long. It has a single trunk, which can grow to be 12 inches in diameter. A tree fern requires a spot in the shade and in an area that does not have high winds. It also needs lots of moisture during its growing season to thrive. One of the most popular tree ferns is the Australian tree fern.
Lay mulch around the base of the tree ferns to help conserve water during the summer. Approximately 2 to 3 inches of organic mulch, such as pine needles, leaf mold or bark mulch, will work well.
Water near the base of the tree fern rather than from overhead. Usually, tree ferns only need supplemental water (water other than from rain) during the growing season, from spring until fall. During that time, water once a week with about 1 to 2 inches of water when rain is scarce.
Stop watering a tree fern in the winter. They go dormant and do not need water at that time.
Cease watering when the fronds begin to turn brown or become spotted with black spots. This is a sign of overwatering. Once the soil dries a couple inches deep, begin to water again, but perhaps, on a biweekly basis and only when rain is scarce.