Marattia douglasii, commonly known as the King fern, is a perennial herbaceous fern native to the moist, shaded understory of Hawaiian Island's forests, particularly in areas with high humidity and stable temperatures. It is a large and robust species, with fronds that can reach several meters in length, creating an impressive display of lush greenery. The fronds are bright green and have a distinctive, leathery texture, contributing to the plant’s prehistoric appearance.

King fern is valued for its dramatic foliage and is occasionally cultivated in subtropical and temperate gardens, where it can serve as a focal point due to its size and form. It requires a consistently moist environment and thrives in rich, well-drained soil with high organic content. In cultivation, it is best suited to shaded or semi-shaded locations that mimic its natural forest floor habitat. While it is not prone to many diseases, it can suffer from root rot if overwatered or planted in poorly draining soils. Due to its size, it is not typically used in small gardens but can be an excellent addition to larger landscapes or as a specimen in botanical gardens.CC BY-SA 4.0