Spring Ephemerals Step into the Light. Bill Cullina

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1 Spring Ephemerals Step into the Light Bill Cullina It is one of the facts of nature that wildflowers in the woodland wake up faster than their counterparts in the sun. Woodland wildflowers have to act quickly once the ground thaws, risking a late freeze for the chance to grow non-shaded by trees for a few weeks each spring. At this time of year, most of the sun reaches the forest floor under oaks, maples, ash and beech, so conditions are perfect for growth and flowering. Later, as the trees come into leaf, many woodland wildflowers simply go dormant until the fall or the following spring. Meadow wildflowers such as asters, coneflowers, Joe-pye weed, bee balms, and phloxes emerge much more cautiously because they have a whole growing season in the sun to look forward to and there is no point risking tender growth to a late freeze. As a consequence, my sunny perennial beds look very barren in April and even May a stark contrast to the waves of color washing through the woodland garden. Two gardens in one To combat this barrenness, many gardeners plant bulbs such as crocus and daffodils among their summer-blooming perennials for a splash of early color. The blubs bloom early then go dormant to make way for the flowers of summer. While we do not have many true native bulbs that would serve as alternatives to tulips and daffodils, there are a number of woodland wildflowers that grow surprisingly well and bloom prolifically in full sun. Just as the spring flowers begin to yellow and slumber in June, the summer and fall bloomers begin to grow in earnest. It is like having two gardens in one and it works out so well that I only wish I had thought of it earlier. You might find it surprising that woodland wildflowers thrive in the sun, but as I mentioned above, even in the woodland they are exposed to very bright sunlight early in the growing season so they have the means to deal with brighter light. They can handle the more intense sun at this time of year because the temperature is relatively cool and soil moisture abundant so stress is minimized. I fact, most of these ephemerals (meaning they come up early in the spring then go dormant by the beginning of summer) grow more compactly and bloom much more lavishly in at least partial sun than they do in the shade. Leaves that emerge in the sun are usually thicker and have more red pigment suffused

2 through them to shield the tissues from UV radiation. The extra sunlight means more energy for flowering and seed production. As the days get warmer, these typically lowgrowing plants become shaded by taller companions and by the time they yellow and go dormant you hardly notice them because beds have filled in with summer flowers. More time for flowering One of the things you realize when you grow these and woodlanders in the sun is that their life cycle is sped up by a week or two. They emerge, bloom and go dormant a bit earlier than their shaded brothers. Fortunately, though, because they produce more flowers, blooming is often extended over what it would have been in the woods. Try some I think you will pleasantly surprised! What follows are some of the woodland wildflowers that have worked well in sunnier areas that have worked well for me. The plants are usually only available in early spring, and The New England Wild Flower Society nurseries grow most or all of them every year. Erythronium americanum and Erythronium albidum (trout lily and white trout lily). Trout lilies are familiar spring wildflowers of damp woods and slopes, but in the forest, blooms can be scarce. Most bulbs produce just a single leaf that later sends out a few rhizomes terminating in new bulbs that will emerge the following year. Only occasionally does a bulb get large enough to send up two leaves and a single trumpet-shaped flower. There has been much speculation regarding the cause of this scarcity, but I feel the primary reason there are so few blooms is simply a lack of sunlight. Trout lilies bloom in a bed of ornamental grasses

3 If you scatter the bulbs around in a sunnier location, they will begin to flower much more prolifically. Additionally, the sterile leaves with their lovely stippled appearance grow much more thickly, forming a solid mat during April and May before withering in June. White trout lily is found in the Midwest and south, though it thrives for us in New England. Its bluish-white flowers are also a welcome sight in late April. Dicentra culcullaria (Dutchman s breeches) and Dicentra canadensis (squirrel corn). These charming little relatives of the familiar bleeding heart are typically found in rich woodlands, but ants carry off their seed and voles and mice carry off their bulbs, so they often wind up in summer places around the garden. For many years we had some great patches of Dutchman s breeches in front of the greenhouse at Garden in the Woods where glare from the sun made things very hot in the summer. The plants grew into very robust clumps and bloomed extremely prolifically in spring, then quickly disappeared underground before it got hot. Both of these Dicentras have soft, gray-green foliage that forms a thick, temporary carpet beneath the sprays of ivory blossoms. Squirrel corn has round corms about the size of a large fresh pea while Dutchman s breeches grow from a scaly bulb. Dicentra canadensis (above) D. culcullaria (right)

4 Squirrel corn blooms 7-10 days later, so I usually mix the two for a longer bloom period. They seed and spread reasonably fast especially when they get some sun, but plant them about 12 inches apart for best effect. Claytonia virginica (Virginia spring beauty) and Claytonia carolina (Carolina spring beauty). Like the Dicentras, these low-growing woodland wildflowers are spread about by small mammals intent on digging and cashing their nutritious little corms. In the nursery we regularly found pots of one plant or another filled with tufts of spring beauties that had been stashed their by a forgetful mouse. As a consequence spring beauties also make their way into the sun occasionally, and here they grow far more lushly and bloom more heavily than they would in the shade. Cheery drifts of little pink flowers are just the thing to transform a dreary spring garden: it s a thing of beauties. Claytonia virginica Thalictrum (Anemonella) thalictroides (rue anemone). There are some striking though expensive cultivars of this little wildflower on the market, including the famous Schoaf s Double Pink with its rich rose pompom and Cameo, (pictured left) whose double blooms are palest pink. The typical form of the species is white, though pinkflowered forms are also available. Any way you slice it, this delicate spring ephemeral is a crowd-pleaser. The upward-

5 facing flowers appear suspended above whorls of columbine-like foliage that springs from knobby tuberous roots as soon as frosts depart. The plants bloom longer and much more heavily when they receive at least three hours of sun, even carrying on through the month of June before finally going dormant. Single forms readily set seed that tends to fall beneath the plants and germinates the following spring. Look for the little seedlings and try to avoid weeding them out as this is the fasted way to grow a large patch. The typical form of the species Seedlings Isopyrum (Enemion) biternatum (false rue anemone) looks superficially similar though its flowers are borne on taller racemes. It is one of the first to emerge and first to go dormant again. Both of these plants appreciate a soil that is not too acidic, so a sprinkle of lime every year or two is a good idea. Isopyrum biternatum in the sun

6 Mertensia virginica (Virginia bluebells) During late April and early May, the woodland beds at Garden in the Woods glow with the ethereal blue of Virginia bluebells. So magnificent is the display that in many years, this is the most popular plant in the nursery. Mertensia virginica is a larger plant than the others profiled so far, and as such it is more prominent both in flower and as it yellows and dies back in June. It self-sows willingly (image of seedlings below), and after several years a few plants may become dozens carpeting the garden with their bluish green leaves and cerulean flowers, As the foliage withers in June, it is not particularly attractive in the woodland, but in the sun when mixed with large summerbloomers, the yellowed leaves are obscured by the flush of new stems appearing around them. Refrain from trimming back the spent stems until they have completely yellowed as the plant needs to draw everything it can into its woody roots for its long slumber. Sanguinaria canadensis (bloodroot) Though its large white flowers are with us only for a few days, bloodroot flowers so early that its brevity is easily forgiven. The unique catcher s mitt-like leaves that follow the flowers persist well into the summer. They are seldom damaged by the strong sun if plated amidst taller perennials that cast some shade just as the season is heating up. The leaves are held more vertically when growing in the sun to deflect some of the sun s rays. After three or four years, you can dig, break apart and reset the shallow, fleshy rhizomes to increase your patch.

7 Dodecatheon species (Shooting Stars) Writers often refer to shooting stars as the primroses of North America and for good reason: like European primroses, they emerge very early in spring as a rosette of soft, lettuce-like leaves. Before the leaves have finished expanding, a tall stem shoots up from their center and unfurls pointed buds that open into remarkable, downward-facing flowers with upturned petals. The flowers open one after the next to form a candelabra of sorts above the leaves. There are three species in the east and more in the west, though all they are all pretty similar in appearance and cultural needs. My favorite is Dodecatheon amethystinum (jeweled shooting star - right) as its light to rich pink flowers are especially colorful. Dodecatheon meadia (eastern shooting star - left) is typically white but will also grade into light pink. All the species prefer a soil that is damp to wet in spring but which dries out somewhat during their summer dormancy. They do very well in partially sunny areas and like the others on this list lend some early color to the garden. Once you start moving woodland wildflowers in to the sun, I think you will find many really do thrive in their new, brighter surroundings. Try some I think you will pleasantly surprised!