Made in the Shade

The two questions we hear most often from home gardeners are “what grows in the shade?” and “what won’t deer eat?” There is a great answer to both questions: ferns!

We have an amazing variety of native ferns in the northern US. There are ferns for wet or dry shady areas, ferns that grow tall and ferns that stay short, ferns that form tidy well-behaved clumps, and ferns that run wild, filling in large areas for groundcover or erosion control. Some ferns are happy in deep shade, and others like more sun than you might expect. Ferns can be dramatic accents in the garden, or create soothing, naturalistic vistas. And all of them are ignored by deer, rabbits, and woodchucks.

Ferns are ancient. Fossils more than 220 million years old have been found of the very same fern species that grow in our forests and gardens today. Apparently, dinosaurs didn’t eat ferns either! Here are a few of our favorite ferns for home gardens:

Cinnamon Fern

For drama, use Cinnamon Fern (Osmunda cinnamomea). Named for the tall cinnamon-colored stalk that rises out of its center, Cinnamon Fern can be a focal point in the garden. It grows 3 to 5 feet tall, with lush fronds extending just as wide, and almost has the tropical look of a palm. It does well in shade, but as long as the ground is damp, it will get even bigger with more sun. In early spring, it looks positively alien as it emerges from the ground covered with fuzzy hairs that disappear as the fronds unfurl. In the fall, Cinnamon Fern turns bright yellow before going dormant for the winter.

Cinnamon Fern emerging in early spring

For a front-of-the-border charmer, use Lady Fern (Athyrium filix-femina). Forming well-behaved clumps with an airy grace, Lady Fern does well in part-shade and even moisture. A cultivar called “Lady-in-Red” has deep red stems that contrast with its fresh green fronds. It will grow 2 to 3 feet tall and wide, and will stay politely where you put it.

Lady Fern with Rhododendron
Athyrium filix-femina “Lady-in-Red”

If you want to cover a lot of terrain, and collect a bonus edible veggie, Ostrich Fern (Matteuccia struthiopteris var. pensylvanica) is the way to go. With adequate moisture, Ostrich Fern will grow 3 to 5 feet tall in shade or sun, and spread itself aggressively. It grows in defined clumps, but sends out runners that form new clumps in time. It can be controlled easily enough by severing the runners and digging out the new plants — or by eating them! Fiddlehead ferns are delicious. They should be harvested in early spring when the ferns are just emerging from the ground and getting ready to unfurl. Cut the emerging fiddleheads with a bit of the green stem. Wash them and peel off any papery covering. They are great steamed, or sauteed in a little butter with salt, pepper, and a bit of garlic.

Ostrich Fern makes a gorgeous groundcover
Fiddleheads from Ostrich Ferns are delicious!

Another garden favorite is Maidenhair Fern (Adiantum pedatum). The unusual circular fronds sit on top of a slender stem (petiole), about 18 inches tall, with fluffy “feathers” arranged around the circle. They are much tougher than they look and combine well with other shade plants. In rich, moist soil, they can take quite a bit of sun without wilting. Their lacy texture is beautiful contrasting with broad-leaf plants like Wild Ginger, Coral Bells, or Rhododendron.

Maidenhair Fern with Wild Ginger

One of the most ancient ferns is also one of the most interesting. Interrupted Fern (Osmunda claytoniana) sends up stalks with fresh green leaves, then appears to change its mind as the stalk develops curly brown “flowers” in the middle, then changes its mind again and continues with green. These “interrupted” stalks are the fertile spore-bearing part of the fern. Once the spores mature and drop, the fronds arch gracefully, up to 4 feet high, for the rest of the summer. Clumps of Interrupted Fern will expand very slowly over the years providing a strong architectural feature to the garden.

Interrupted Fern bearing its spores in mid-stem
A 30-year-old stand of Interrupted Fern stays fresh and vertical all summer

Christmas Fern (Polystichum acrostichoides) has the great virtue of being evergreen. It does well in dry shade, and needs no care at all. You can find it easily while walking in northern woods in the winter time, and it makes a great evergreen groundcover under trees and shrubs in the home garden. It stays low, under 2 feet typically, and spreads only very slowly. But if planted densely, it makes an attractive year-round groundcover.

Christmas Ferns planted at the Nature Center
December in the Nature Center’s forest

All of these native ferns are hardy to Zone 3 and need very little care. They are woodland plants, so they like soil naturally enriched with fallen leaves and decayed plant matter. Try a few in those troublesome, shady and deer-browsed spots. Or plant a whole fern garden and try them all!

Fern garden in spring: (clockwise from upper left) Cinnamon Fern, Interrupted Fern, Christmas Fern, Maidenhair Fern

A Small Wonder That Makes Us Wonder

There is a fascinating little plant, just emerging now in the early days of spring, that is a marvel of evolution. It is also one of our favorite native ground covers for shade.

Asarum canadense, Wild Ginger, is native to shady forests from Northern Canada all the way south to Georgia and west to the Dakotas. It has beautiful leaves that grow in pairs like rounded hearts. It grows very close to the ground, never more than 3 or 4 inches high, and it forms lush mats that densely cover a slowly expanding area. It spreads about 6 inches in each direction every year.

Wild Ginger and Trout Lily hug the ground in a shady spot

Underneath the pretty leaves, Wild Ginger hides its secret flowers. There are lots of flowers, but you have to get down low and push aside the leaves to find them. The flower stems and leaf stalks (petioles) are covered with downy hairs that give them a furry appearance. The flowers are purplish brown, with 3 pointed petals that open to a little cup where the stamens with pollen are hidden.

Wild ginger flowers hide under the leaves
Stamens with pollen are tucked inside the flower

Botanists believe that Wild Ginger evolved with its flowers right next to the ground to attract early-season flies as pollinators. Flies emerge from the ground looking for carrion. They promptly find the brownish flowers of Wild Ginger right on the ground and crawl inside. There they hide from rain and the cold nights of early spring, snuggling into the cup-like flowers and accidentally collecting pollen on their bodies that will be transferred to the next flower they visit.

Seeds develop in the pollinated flowers, and when they ripen, they are discovered by ants. The seeds have oily little appendages that are nutritious and delicious to ants who carry them off to their colonies. The ants eat the oily part, but abandon the seeds to germinate. Not only are the seeds protected this way from seed-eating animals, but they are effectively planted by the ants.

Wild ginger growing under a cherry tree
Did ants carry Asarum seeds up into the crook of the tree?

Wild Ginger is in the same botanical family, Aristolochiacea, as our native Pipevine, the host plant for the gorgeous Pipevine Swallowtail butterfly, and many experts believe that Wild Ginger is an alternate host plant for the Pipevine Swallowtail caterpillar.

Wild ginger does indeed taste like ginger, though eating much of it may be toxic and is not recommended. Indigenous Americans dried the tubers and ground them as a spice. Early colonists boiled the tubers with sugar water, making something like candied ginger and then used the cooking liquid as a syrup. Both groups used the plant as a poultice to treat wounds, and modern research has confirmed the presence of two antibiotic compounds in the plant.

Today, we know Asarum canadense best as a fantastic shade ground cover. It preserves soil moisture and suppresses weeds all summer. It is deciduous, so it uncovers bare ground for the winter, which benefits ground-nesting native bees, flies, and beetles. As a garden plant, it is absolutely gorgeous in combination with ferns and shade-loving grasses. It is ideal under trees and shrubs, as well as in wooded areas, and eliminates the need for mulch. Deer completely ignore it.

Wild Ginger with Maidenhair Fern and Bunny Blue sedge

So, this amazing plant evolved offering shelter to the little flies that pollinate it, feeding the ants that protect and distribute its seeds, and hosting caterpillars that turn into beautiful butterflies that pollinate other plants. It healed the wounds and spiced the food of the earliest humans on this continent. It is beautiful, and perfectly adapted to our climate. It is not difficult to grow, and it does exactly what we want our ground covers to do. It belongs here in every sense of the word. Wild Ginger is a perfect example of the benefits of native plants.

Why, then, do we see so much pachysandra, ivy, vinca, wintercreeper, and other non-native ground covers escaping suburban yards to infest our woodlands, suppress native plants, diminish food sources, and even pull down our trees? Why would we choose those imported plants when the perfect plant always has been right here?

We can’t help but wonder.

Pachysandra and vinca destroying forest

The Redbuds Are Coming!
The Redbuds Are Coming!

Long before Paul Revere made his historic ride, Redbuds were alerting everyone to the arrival of spring.

The Eastern Redbud (Cercis canadensis) is a small understory tree that shares the dappled edges of woodlands with two other American classics – Amelanchier and Flowering Dogwood, both featured here in earlier posts. Amelanchier (Serviceberry) is the first to bloom, followed by Redbud, and then Flowering Dogwood. If you are looking for a small flowering tree, skip the invasive Callery (Bradford) pear, take a pass on the Asian cherries, and go for one of these historic native beauties.

Redbud announcing spring at the Nature Center

Redbuds are unusual in that the flowers emerge along the branches, stems, and even the trunk of the tree. The flowers range from soft pink to deep fuchsia, and sometimes even in white. The tree is in the legume family and the flowers do look like pea blossoms. Long-tongued bees, like carpenter bees, reach deep into the flowers to sip nectar and emerge covered in pollen. The seeds are encased in something like pea pods and may remain on the tree all winter.

Redbud flowers emerge directly from the wood
Flowers may sprout even from the tree trunk

The leaves of Redbuds are large, somewhat shiny, heart-shaped, and are the host for Henry’s elfin butterflies. Perfect for smaller properties, the trees rarely exceed 25 feet in height. They have a rounded shape and look pretty even in winter. Fall color typically is not spectacular, but one recent introduction, ‘Forest Pansy,’ has beautiful purple leaves that turn deep red in the fall. And there is an interesting weeping form called ‘Lavender Twist’ that resulted from a natural mutation that has since been propagated by horticulturists.

‘Lavender Twist” Redbud
Redbud in full summer leaf at the Nature Center

The flowers of the Redbud are edible – either fresh, boiled, or fried. Native Americans ate the flowers, and also used the dried bark of Redbud as a spice. The seeds are edible, too, when roasted.

Spring salad garnished with Redbud and Violet flowers

Our local Redbuds, Cercis canadensis, evolved in the forests of the Eastern US, from southeastern New York to parts of Florida, and are hardy in zones 4 to 9. They are understory plants that grow in shade, but they flower best with more sun. They are happy in average garden soil and are well-suited to suburban yards. There are related species of Redbuds native to the dry heat of Texas, Nevada, and California that will survive in zones 8 and 9.

Redbuds really do have a connection to colonial US history. George Washington wrote in his diary about his particular interest in Redbuds. His initial preference for European plants was fading, and he became increasingly interested in indigenous American plants. He collected Redbud seeds from local forests and planted trees he grew from seed on his own property, no doubt increasing the popularity of our native tree.

A mother robin nested in a Redbud at the Nature Center

So, hear hear! The Redbuds are coming!


A Most Gracious Host

Photo: Travis Brady

This week in Around the Grounds, we learn about the hostess with the mostest.

Amelanchier invites everyone into the garden, sets an elegant table, and makes sure no one leaves hungry. It is the consummate host plant.

Amelanchier (pronounced “amuh-lank-kee-yer”) is a small tree or multi-trunked shrub that will feed bees, butterflies, birds, woodland animals, and humans, all while looking beautiful. You may know it by one of its many common names: serviceberry, shadbush, shadblow, juneberry, wild plum, sugarplum, or saskatoon. While there is debate about the origin of some of these names, everyone agrees that it was called “shadbush” by settlers in New England because its early bloom time coincided with the spawning season of shad fish in northeastern rivers.

Amelanchier blooms in April, covering itself with delicate white flowers, and providing essential nectar and pollen for the first emerging bees. The elegant white blossoms are a welcome sight contrasting beautifully with evergreens. While the flowers remain, bees, butterflies, hummingbirds, and moths all come to visit.

The most common form of Amelanchier is a multi-trunked shrub or small tree
The single-trunked tree form can reach up to 30 feet, but remains open and airy

Leaves appear as the flowers fade, but Amelanchier never creates heavy shade. The leaves are narrow and open, so there is plenty of light for underplanting. A true host plant, Amelanchier feeds an estimated 124 species of caterpillar, including the Viceroy, the Striped Hairstreak, and the Red Spotted Purple. That hospitality makes Amelanchier a very appropriate addition to our Pollinator Garden.

Adult Red Spotted Purple Butterfly
Amelanchier right now in the Pollinator Garden at the Nature Center
Photo: Travis Brady

Our gracious host really sets a fine table in June when the berries appear. That’s when the common names “Juneberry” and “Sugarplum” make sense. Amelanchier berries are not only edible, they are delicious! About the size of blueberries, but delicately sweet like raspberries, Amelanchier berries can be eaten right off the branch or turned into a very fine pie – but only if you can get enough of them before the birds do. It seems that robins, blue jays, cardinals, and mockingbirds all are willing to eat the berries a day or two before we think they are ripe. And we have seen chipmunks and squirrels risking life and limb to climb way out on swaying branches to get their fair share. Most years, we humans only get a handful or two of berries.

Amelanchier berries ready for everybody
Get ‘em while they last!

Botanically, Amelanchier is complicated. The genus includes over 20 species with native ranges from Canada and Alaska across the entire northern US, with some species even in Arizona and Florida. The best garden varieties in the northern US are Amelanchier arborea and Amelanchier laevis, both found in the taller tree form, and Amelanchier canadensis, which is more typically the multi-trunked shrub form. All three are hardy in zones 4 – 9 and prefer conditions typical of woodland edges, light shade and moist, fairly rich soil. These and other Amelanchier species freely interbreed both in the wild and in nursery conditions, so natural hybrids are common and very difficult to tell apart. If you’re shopping, you can choose a single trunk or multi-trunked specimen, and take whatever the label says with a grain of salt. But you really can’t go wrong.

After all, a gracious host like Amelanchier never turns a guest away from the garden….


Marvelous Milkweed – Not Just for Monarchs!

This week on Around the Grounds, we learn about the wonders of Milkweed and why it should be a staple in every home garden.

Last week in Around the Grounds we joined the happy buzz about pollinator gardens springing up everywhere. We know that bees need native flowers for nectar and pollen. Butterflies also need nectar, and they need the host plants their caterpillars eat. So, a good pollinator garden supplies all three resources – nectar, pollen, and host plants. Planting a big variety of native plants is the best way to do that.

However, there are a few special plants that do all three jobs. Top among them is Milkweed (Asclepias spp.). Milkweed, of course, is the only host plant for Monarch butterflies.

A Monarch caterpillar

If you go looking for monarch caterpillars on Milkweed, you may discover an entire, complex ecosystem. A research study in Ohio documented 457 different insect species on just one stand of Milkweed! That’s a lot of biodiversity supported by this amazing plant.

In addition to monarchs, Milkweed is the host plant for 11 other species of Lepidoptera (the insect family for moths and butterflies). One of them is the Milkweed tussock moth. Many a gardener has been shocked to discover a mass of little wriggling black caterpillars rapidly devouring their prized Milkweed plants. But before you panic, consider the careful balance nature has designed.

The Milkweed tussock moth arrives later in the season, after most of the Monarch caterpillars already have eaten their fill and turned into butterflies, so there is plenty of Milkweed for everybody. As these little black caterpillars mature, they wander away from the pack and grow from creepy to… sort of cute? But don’t touch them without gloves. Those funny hairs can sting like nettles.

Milkweed tussock moths are important night-pollinators, and their main predator is bats. Astonishingly, they have developed a defensive sonar-type beep that warns bats away from them.

Milkweed tussock moth caterpillar
Photo: M.J. Raupp

Another common sight on Milkweed is a large population of Milkweed aphids. You could hose them off, or squish them with your fingers. Or, you could just watch as ladybugs show up to feed on them. Ladybugs are very effective insect-eaters. One ladybug can eat up to 50 aphids a day. Lacewings, tiny parasitic wasps, and several other beneficial insects also are likely to join the aphid hunt, so the aphid situation seems to take care of itself in our garden.

Ladybugs feeding on Aphids

We’ve found walking sticks, praying mantids, ants, bees, flies, wasps, spiders, and specialized Milkweed bugs and beetles, all living their best lives on Milkweed.

You never know what you’ll find on the underside of Milkweed leaves
A spider sets up shop to see what wanders in
Milkweed bugs eat the seeds in late summer and fall 
Photo: Travis Brady

Oh! Did we mention butterflies? Milkweed is loaded with nectar and draws ALL the butterflies – not just Monarchs. 

Spicebush swallowtails in mating dance on Milkweed

While the best Milkweed for supporting all of this life is probably Common Milkweed (Asclepias syriaca), that species is rather big, coarse, and an aggressive spreader for smaller gardens. Sadly, it’s the loss of Common Milkweed from roadsides, farmyards, and wild places all the way from Mexico to Canada that has caused the tragic decline of monarch populations.

But gardeners are making a difference, and with beautiful Milkweed species for smaller gardens, it’s really easy to do. Swamp Milkweed (Asclepias incarnata) grows 3 – 4 feet tall and blooms for months. Its lavender-pink flowers blend in with lots of other sun-loving perennials. It is perfect for pollinator gardens, meadows, and mixed borders. And it also comes in white!

Swamp Milkweed (Asclepias incarnata) is a butterfly magnet
Asclepias incarnata ‘Ice Ballet”

Every garden can find a place for Butterfly Weed (Asclepias tuberosa). This lovely Milkweed is a perfect front-the-border plant. It grows about 2 feet tall and is fairly compact. It stays where you plant it and is reliably hardy. The straight species is a sunny orange, and there is a bright yellow cultivar called ‘Hello Yellow.’ Butterfly Weed does best in full sun and well-drained soil. It rarely needs supplemental water, and never needs fertilizer.

Butterfly weed (Asclepias tuberosa) at the Nature Center 

Whether or not you are planning a pollinator garden, if you love nature, be sure to add marvelous Milkweed to your spring planting list.