Since more and more people are expressing interest in ecofriendly gardening, I thought I'd share some hardy, native Minnesota plants that require minimal care and add texture and color to your ornamental landscaping. This month I will highlight native Minnesota ferns.
Ferns are some of the oldest plants; they can be traced back 300 million years in the fossil record! Over this long period they have developed many different forms and textures to suit a myriad of landscape purposes. Ferns are relatively easy to grow given the proper conditions. Woodland ferns are the easiest and most adaptable to grow. Most require a rich, slightly acidic soil with good drainage. Ferns do best in full to partial shade, and can be planted in the spring when the soil is dry and warm. (If you can make a mud ball with the soil, it's too wet!) If you've never grown ferns, here are a few Minnesota native varieties to try.
Sensitive Fern (Onoclea sensibilis) are the easiest of the native ferns to grow in your garden. This coarse textured fern has pale red fiddleheads which mature to deeply pinnate yellow/green leaves that can grow up to three feet long. The brown reproductive "sori" are clustered like beads. Sensitive ferns spread to form colonies and can become weedy if not managed properly.
Interrupted Fern (Osmunda claytoniana) is a native Minnesota fern very similar to its cousin the "cinnamon fern". It develops a rosette of straight, deeply pinnate, narrow, nearly vertical leaves about 2-4' tall. This fern prefers dappled sunlight and moist soil. The spring emerging fiddleheads are silvery white.
Maidenhair Fern (Adiantum pedatum) are very distinctive with dark stems and deeply cut bright green foliage. The spring fiddleheads are reddish brown. They prefer deeply shaded, well drained sites, and have been known to grow along rock walls and around waterfalls. It is an excellent choice for naturalizing along hillsides and many other shady locations. It does need protection from winter winds.
Ostrich Fern (Matteuccia pensylvanica) is one of our tallest native ferns. The finely pinnate leaves are medium green, and have been known to grow 5'tall, looking much like the plumes of an ostrich, hence the common name. They prefer medium to wet soils and shade, but will grow in full sun with constant moisture. This fern spreads via underground runners, and is an excellent choice for naturalizing. The fiddleheads can be used as a cooked vegetable, and are considered a delicacy in many areas of North America.
For more information about growing ferns in your garden, visit: http://www.sustland.umn.edu/maint/ferns.html
Until next time, sweet garden dreams!
Robin Trott is a Horticulture Educator with University of Minnesota Extension.