Scientific Name: Nephrolepis cordifolia
Indigenous: All HI
Description: A type of sword fern with erect fronds standing 1-2 ft. tall and 2-3 inches wide. Each frond is comprised of many smaller pinnae (frondlets), each about 1-11/2 inches long and about ¼ inch wide. Generally, these ferns are terrestrial meaning that their stolons (sprawling stems of ferns, which look like roots) spread out across the surface of the dirt but occasionally they will be epiphytic, crawling up trees or tree ferns. The most distinguishing characteristic of this fern is that it is the only species of Nephrolepis in Hawaii to have underground tubers that develop on the stolons which serve as food storage as well as a means to reproduce since new ferns will develop from it.
Distribution: This indigenous fern is found throughout the tropics and is a common fern in cultivation. Here in Hawaii it is fairly common and found on all the main islands in mesic (somewhat wet) to wet forests.
Cultural Use: It was often used to decorate hula altars symbolizing that it was a place of learning, or sprouting knowledge since the word kupu means to sprout. The fronds are also used for making lei.
Landscape Use and Care: Plant kupukupu in either full sun or partial shade. It looks great as an accent plant around landscape pohaku (stones) or planted as a mass groundcover, the only thing with that is to not plant them too close. Each fern should not be planted closer than 18 inches apart. This is because they can out-compete each other and eventually die back in a short amount of time. You can also plant them at the base of a rock wall and they will slowly crawl up the wall sprouting new ferns in various crevices. Daily watering is fine as long as they are planted in well drained soil. Don’t allow the fern to sit in standing water, it will start to turn yellow and defoliate often dying.
Additonal Info: There are at least five different species of Nephrolepis found here in the wild of these only two are native, this one described here and another larger species named Nephrolepis exaltata subsp. hawaiiensis which is an endemic subspecies. The other three are naturalized aliens species that can be very invasive. The problem with this is that they can and often will hybridize with the native species jeopardizing the genetic integrity of them.
Kupukupu