Australian Tree Fern Information

Australian tree ferns, often planted around water to create a double image, are sure to catch the eye of passersby. These tree ferns are commonly grown in commercial landscapes as well as gardens in areas of the country that do not experience freezing temperatures. These tropical beauties are very popular and recognizable as well as easy to grow when their needs are met.

Geography

Grown naturally in tropical or subtropical climates, two native tree fern genera with 15 different species are in Australia. Tropical regions in the United States–those in USDA (United States Department of Agriculture) Plant Hardiness Zones 9 or 10–will support the Australian tree fern well. Because of their tropical nature, Australian tree ferns cannot cope with freezing temperatures. However, they are grown as potted plants in more northern regions, where they must be brought indoors during winter.

Size

Depending on the conditions, the tree fern may be fast growing, as it becomes a medium or even large tree fern with a mature height of around 50 feet and a trunk that can be as much as 12 inches in diameter. The widely spreading crown with its fronds that are light green can range from 13 to 20 feet across.

Considerations

Being ferns, shade is necessary for these trees to survive, because they are not sun lovers. They also require a great deal of space, which may make finding a location more difficult. Although this tree fern is not native to Hawaii, it has become naturalized there and is considered an invasive and aggressive species. Usually disease resistant, the fern can be invaded by termites that live in the trunk and also attacked by mealy bugs and mites. However, these pests do not normally affect the health of the tree in the long term.

Growing conditions

Australian tree ferns need partial to full shade, as they do not do well in sunny locations. Be certain to choose a location that has sufficient space for the plant to reach its full potential growth without crowding other plants or buildings. The Australian tree fern needs well-drained soil containing organic matter worked in about 1 foot deep. The soil needs to be moist but not saturated, and weed free in a 3-foot circle around the tree. Mulching is recommended to help control weeds and keep moisture in the soil. Fertilize with a granular 10-10-10 mixture early in spring, during summer and again in the fall around the drip line of the tree. Water this well once applied.

Fun Fact

Propagation of Australian tree ferns occurs only from spores that occur on the bottom of the mature fronds.

References

• University of Florida.edu
• Red Orbit.com
• Garden Guides.com