Go Native!

by Mary Jasch

Now is the time to think about planting your garden with East Coast wild flowers. The understated elegance of native flowers, their hardiness, low maintenance, and interaction with wildlife make them desirable plants for our cultivated landscapes.

At the New England Wild Flower Society's botanical garden, Garden in the Woods, in Framingham, Massachussetts, horticulturists collect seeds from May through late November.

The 45-acre Garden in the Woods contains the Northeast's largest cultivated collection of over 1,600 kinds of wild flowers, ferns, shrubs and trees, many rare and endangered.

“We collect the seeds of almost 400 species to grow the plants for people to buy, and we also collect extra for people to buy the seeds and grow the plants themselves," says Cayte McDonough, plant propagator.

NEWFS sell seeds of over 200 species, including 35 woody plants for the extra enjoyment of those who like to grow plants up. Three magnolias grown in this cold climate are well worth trying: cucumber magnolia (Magnolia acuminata), umbrella magnolia (M. tripetala), and Ashe's magnolia (M. ashei), which is found growing in the Florida panhandle.

“A lot of plants found in the wild in the south are hardy here," says McDonough, “but the glaciers have pushed them south and they haven't migrated here yet." Although NEWFS doesn't carry the seed of sweetbay Magnolia, M. virginiana, considered to be a more southern tree, it grows on the Massachusetts coast.

Out of the hundreds, here are a few recommendations from Cayte McDonough:

The Challengers
Looking for an unusual plant to grow from seed? Try Turkeybeard, Xerophyllum asphodeloides, native to the NJ Pine Barrens. In spring, a three-foot stem with a rounded head of creamy white flowers rises above a tuft of foliage that looks like stiff grass. "The plant takes three to five years to bloom but the flower is magnificent. It grows in sun to part sun in well-drained acidic soil. Turkeybeard germinates early but should not be transplanted until the second spring. It will bloom after another 3 to 5 years of growth. The challenge of Turkeybeard is during transplanting. Do not plant too deep or too shallow, but just right - even with the original soil line. This plant does not tolerate carelessness."

Or how about raising a queen? Tales of doom abound about trying to grow Lady's-slipper orchid. Astonished plantspeople are stumped, but McDonough knows the answer -- these regal wild flower seeds contain no endosperm, a sprouting plant's initial food source.

So the question becomes: do you have the Rhizoctonia fungus or not? If you do, your seeds will likely germinate after three years; if not, probably not. This particular fungus infects the dustlike Lady's-slipper seed, providing nutrients and sugars during germination and early growth. Once they germinate and grow, they don't seem to need the fungus.

So how to tell if the fungus is present in your soil? If other Lady's-slippers are growing in your yard, chances are good for a positive infection. Otherwise, check the NEWFS website below for information on how to test for the fungus.

Lady's-slippers grow wild in the Garden in the Woods and seed is available for Pink Lady's-slipper (Cypripedium acaule), pale yellow-mahogany Kentucky Lady's-slipper (C. kentuckiense), and small yellow (C. parviflorum) and large yellow (C. pubescens) Lady's-slippers. NEWFS also sells containerized plants. “We have stock beds of mature plants that double the number of stems each year. We divide them and sell off the divisions,"¯ McDonough says.

Many native plant seeds require a double dormancy. That is, they sit in the soil for two winters before they fully germinate. "They usually have a two-stage germination, putting out a root radicle in the first year with the first above ground growth appearing the next year," McDonough says.

One such plant is Trillium, another challenger. Its seed takes two years to germinate and the plant takes another three to five years to reach blooming size. One must be devoted. NEWFS has white blooming 'Showy' Trillium (Trillium grandiflorum) and the burgundy/red Whippoorwill (T. cuneatum) with silver/green mottled leaves.

The Big Easies
“Some seeds you can sow and they will germinate readily at warm temperatures; others require being cool and moist for 60 to 90 days. Then when it's warm they'll germinate,"¯ says McDonough. That includes eight kinds of aster seed for woodland and open areas. Most bloom in late summer and fall. Blue wood aster, Aster cordifolius, has heart-shaped leaves and thick clusters of blue flowers. It grows in sun or shade on moist or dry soil. Taller New England aster, A. novae-angliae, with violet to lavender flowers likes moist soil in sun or part sun.

There's a milkweed for every spot. Orange Butterfly Weed, Asclepias tuberosa, likes dry soil and sun, and the pink and white swamp milkweed, A. incarnata, a nectar source for butterflies, likes average soil in sun to part sun. They both bloom in July.

For the rock garden, try the red wild columbine, Aquilegia canadensis. This adaptable and compromising plant gives great blooms in rich soil, but dies young there. In less fertile rocky places, it lives longer with fewer flowers. In the wild, it seems to grow straight out of rock. It likes well-drained soil with sun to light shade. "In the wild, I've found it growing in pockets of soil on rocky ledges. In my garden, it grows well in soil that I've amended to be well-drained," McDonough says.

Some of the first seed collected by NEWFS propagators is Spring Beauty Claytonia virginica and Carolina Spring Beauty, C. caroliniana. The last is summersweet. Summersweet, a.k.a. sweet pepperbush, Clethra alnifolia, is native to the Pine Barrens. Grow it for its fragrant flowers that are important nectar sources. It grows easily from seed sown indoors. Cinnamon clethra, C. acuminata, grows in old growth Smokey Mountain forests and has cinnamon, grey and bronze-colored exfoliating bark. Both clethras like it moist and bloom in late summer.

In November, McDonough and crew sow wild flower seeds in flats in a seedling mix, then place them outside under an insulated blanket and plastic cover so the seeds go through natural temperature fluctuations. “We allow them to freeze. We usually uncover the nursery in late winter once temperatures get into the lower 40's somewhat consistently,"¯ she says.

McDonough has learned the complexities of seed production over the past six years at Garden in the Woods. “I love plants and have a passion for growing plants from the very beginning. I love the idea of promoting plants that are native to this continent. There are a lot of organisms that are interdependent on native plants. Birds and butterflies feed on these plants."¯