For a garden writer, regional botanical gardens are grist for the mill, always worth the journey for the new plants and new gardening ideas that I can share with my readers. A recent rainy morning visit to the Berkshire Botanical Garden in Stockbridge, Massachusetts, provided the perfect hiatus from the summer routine in my own garden. Despite less-than-perfect weather, I discovered several new garden plants as well as many familiar plants used in refreshing creative designs.
This summer’s visitors to the Berkshire Botanical Garden are met as they leave their cars by a welcoming riot of color, an island bed filled with exuberant annuals including orange-red zinnias (‘Profusion Fire’) and yellow-orange coneflowers (‘Prairie Sun’). At the back of the bed, ‘Black Ruffles’ elephant ears (Colocasia esculenta) wave giant purple-black leaves over the coneflowers, their color echoed by the ornamental sweet potato, Ipomoea battatas ‘Blackie’, at the bed’s front edge.
One of my favorite annuals is the tall flowering tobacco, Nicotiana alata, especially the cultivar ‘Only the Lonely’. I grow it every summer, often in pots, and it self-sows in the vegetable garden from seed in compost, tall leafy stalks topped with sprays of tubular white flowers along the edges of the September garden beds. Wherever it flowers, heady perfume fills the air at dusk, attracting hawk moths that hover in front of the flowers as they sip nectar through their long tongues.
The gardeners at Berkshire Botanical Garden planted ‘Only the Lonely’ at the back of a border along the gray wall of a garden shed. Suddenly coming across this planting as I toured the garden felt like a chance encounter with an old friend. I was pleased to see that others value this annual as much as I do.
There is an enchanting children’s garden at Berkshire Botanical Garden, complete with chicken coop and a wishing tree on which visitors of all ages hang a tag with their heartfelt wishes. This summer a Mexican sunflower, Tithonia rotundifolia ‘Torch’, grows along a split-rail fence that surrounds the children’s garden, its potato-like foliage covered with 3-inch flaming orange flowers. This impressive annual is a must for every butterfly garden, hummingbird garden, and pollinator garden. I’ve already decided where to grow it next summer in Marjorie’s Garden.
A Perennial Coneflower for the Back of the Border
Among the several species of coneflower native to North America and cultivars of those species, Berkshire Botanical Garden introduced me to Rudbeckia laciniata ‘Herbstsonne’, a perennial coneflower that typically grows 4 to 7 feet tall. It belongs at the back of the border or the center of the island bed where its large daisy-like flowers (3 to 4 inches across) with drooping yellow rays and elongated central cones can attract butterflies. The central cones start out green but by August most have turned to a yellow-brown. At any time of year, this coneflower makes an excellent cut flower.
You may find ‘Herbstsonne‘ sold with the cultivar name ‘Autumn Sun‘ and possibly as a cultivar of R. nitida. Some experts believe that it is actually a hybrid between R. nitida and R. laciniata, both native to the southern U.S.
Malabar spinach (Basella alba), otherwise known as Indian spinach, Ceylon spinach, basella, and vine spinach, was flowering on the day of my visit, clusters of pink flowers on purple-red stems winding around slender bamboo fencing. I’ve never grown it but understand that the mild-flavored leaves can be used like spinach in salads and cooking.
I wonder if malabar spinach can be grown in northern New England. The vines only creep in cool weather, leaping when the temperature hits 90 degrees. Plants must be started inside and transplanted to the garden only when the danger of frost has passed. And a period of drought in summer will initiate flowering, which causes the leaves to turn bitter. I think I must give it a try next year, just a simple bamboo trellis, more for the lovely flowers and colorful stems than for the edible leaves.
Succulents in the Gutter
I’m sure it’s been done elsewhere, using a section of gutter mounted to a garden fence rail to grow succulents, but it seemed almost natural in the children’s garden at Berkshire Botanical Garden, a collection of sedums, echeverias, and other succulent plants, some spilling over the edges of the gutter, some in flower. I can think of no lovelier way to grow them.
Those who read this column regularly may recall my fondness for staghorn sumac (Rhus typhina), a native shrub that many find too exuberant for their own gardens and some call aggressive because of its rampant suckering habit. True enough, the tendency to produce suckers several yards from the parent plant would limit the use of such an exuberant species, but I still love it for its beautiful autumn foliage.
On display near the entrance to Berkshire Botanical Garden is a cultivar of this species named ‘Tiger Eyes’, a dwarf, golden-leaved staghorn sumac that grows to only 6 feet tall with minimal suckering. It was discovered in a nursery in 1985 as a mutation of another R. typhina cultivar, ‘Laciniata’, and it is now available to gardeners. The leaves emerge chartreuse in spring, then quickly turn to bright yellow. In fall, they acquire striking orange and scarlet tones. Flowering and fruiting is similar to the species.
Sound too good to be true? I’ve admired the plant at Berkshire Botanical Garden over two years, seeing it first in 2011 and again this August, and it has not grown taller nor exceeded its bounds. The Missouri Botanical Garden considers it “a superior landscape plant to ‘Laciniata’ as well as to the species (Rhus typhina) because of its dwarf size, quality yellow foliage and minimal suckering”. Yet there are a few reports of excessive suckering. And it is pricey. I’ve yet to see one in a private landscape.
To discover plants like ‘Tiger Eyes‘ is why I visit botanical gardens. Grist for the mill.