A flowering fern is a large, shrub-like fern that grows in damp areas where water supply is continuous. The term "flowering fern" is derived from spore-bearing fronds that appear in mid- to late summer and are said to resemble a spent flower. This species has members native to North and South America, Europe, Asia, Africa, and the British Isles. Another widely used common name is royal fern. The scientific name is Osmunda regalis.
A mature flowering fern grows 6 feet (1.8 m) tall and 3 feet (about 1 m) wide. The fronds are from 2 feet to 5 feet (.6 m to 1.5 m) long with delicate green opposite leaves. The fronds are from 12 inches to 18 inches (30 cm to 45 cm) wide. The roots of the flowering fern are black with a portion of the mass raised up to 6 inches (15 cm) above the surface of the soil. The roots also penetrate the soil to reach the underground water table.
Unlike most ferns that thrive in cool, shaded areas, the flowering fern grows well in full sun or partial shade. In the wild it grows alongside rivers and streams, at the edge of ponds, and in open, damp meadows, wet woodlands, marshlands, swamps and bogs. In warm areas, the leaves stay green all year; cooler areas will see the ferns die back in the winter and return in the spring. The flowering fern is hardy to temperatures as low as -4 degrees Fahrenheit (-20 C).
In cultivation, the flowering fern prefers sandy, damp soil with an acidic pH. It can be planted in full sun as long as there is constant access to water, or in light shade with frequent irrigation. Though large, this fern transplants well any time of year; in very hot weather, the fern should be moved in the evening when the air is cool. Flowering ferns are planted near garden ponds, where the deep roots can access the water. In a shrub bed or alone in the landscape, the bright green foliage creates a lush, green backdrop with continuous water.
To propagate the flowering fern, sections of the root can be divided and replanted. The spores, produced in midsummer, can be collected and replanted in damp peat moss or compost in a greenhouse. Once collected, the spores must be sown within three days. Plants grown from spores should be raised in a greenhouse for the first two years before being moved outside.