For the last few years I have conducted seminars on groundcovers and discussed Sweet Fern, Comptonia peregrina. Most gardeners are not aware of this small shrub. Propagation issues have kept it from widespread introduction to the retail nursery trade. This problem has been generally resolved (http://www.amerinursery.com/article-8091.aspx) so availability should multiply.
I discuss this boreal groundcover with others who thrive in poor infertile or rocky soils; Bearberry, (Arctostaphylos Ursa-uvi) , Lowbush Blueberry (Vaccinium angustifolia), Northern Bush Honeysuckle, (Diervilla lonicera) and Common juniper (Juniperus communis). Sweet Fern is a pioneer plant spreading into disturbed soil, it can fix nitrogen and is salt tolerant. Some say it can be invasive.
Found in dry pine or oak woodlands in shallow soils over bedrock. The dominant shrub layer species are Lowbush Blueberries and Northern Bush Honeysuckle with larger Juneberries, Hazelnut, Prairie Willow and Staghorn or Smooth Sumac. The canopy is made of Red and White pine or Red Maple, Pin and Red Oak. The sub-canopy can be comprised of Mountain Maple, Mountain-ash, Quaking Aspen and Paper Birch.
How can Sweet Fern be used in landscapes? Mixed with any of the aforementioned groundcovers Sweet Fern can be used in many tough growing locations. Edges of roadways, sidewalks and drives where salt is sprayed throughout winter, Sweet Fern can be utilized with Bearberry providing varying height. As a turf replacement in any dry growing conditions. Sweet Fern foliage is fragrant adding scent to any area. Wild Rose grows with Sweet Fern in the wild. Shrub roses such as Nearly Wild would add color. Native to rocky environments Sweet Fern could be used surrounding rock clusters.
Seek out Sweet Fern, I hope knowing something of its native ecology can help you find opportunities for this shrub in your landscape.