The nodding flowers in mid to late spring are modest to our eyes but extraordinarily attractive to all manner of forest pollinators. Although usually pale lavender in colour, the flowers of Virginia Waterleaf in the wild can be pure white, a nice mid-range purple, or pale pink. The distinctively lobed leaves emerge in the spring spotted with silver. It is the silvery spots which give the plant the name Waterleaf. Alas, the pretty spots fade as the leaves mature.
Virginia Waterleaf spread by rhizomes and by seeds so, where it is well suited, it can easily form a robust ground cover. It prefers dappled deciduous shade and it is tolerant of heavy clay soils. Thus it is an excellent choice for shady city gardens with compacted soils. If summer droughts have left the foliage looking tattered, the plants can be cut down and they will produce a crop of fresh leaves for autumn.
As gardening for pollinators, and insects in general, has become popular, I see many more customers interested in Goldenrods. The bright yellow sprays, differently shaped for different species, are ubiquitous in old fields and along country roads. Their very abundance gives us clues to how important they are for late summer pollinators.
Grey Goldenrod (Solidago nemoralis) is a short, tidy goldenrod of dry infertile places. It is often found in old fields in areas where the soil is sandy and thus especially dry and infertile.
Very unobtrusive in the early part of the summer, Grey Goldenrod sends out flowering stems (about 30 cm tall) from its basal rosettes in late summer. The ends of the inflorescences tip over in a graceful curve in a way that is characteristic for the species. It is a great goldenrod for sunny urban meadows, combined with a short grass such as Blue Grama Grass. For gardeners who want to provide for late summer pollinators, but who think introducing Canada Goldenrod or Tall Goldenrod to their gardens might send the neighbours into conniption fits (with some justification, as these are large and aggressive plants), the unthreatening Grey Goldenrod might be just right.
Beaux Arbres offers some other garden-worthy Goldenrods: the lovely Blue-stemmed Goldenrod, for shady spots, and Stiff Goldenrod, a handsome clumping plant for flower borders
Beaux Arbres has a few bright, lovely Pasque Flowers plants in our rock garden. We grew this beloved European spring flower from seeds from the Ontario Rock Garden and Hardy Plant Society Seed Exchange, and offered some of our surplus for sale. However, we long wanted to get a good supply of the North American species, the true Prairie Crocus, Manitoba’s floral emblem. We tried several times and our germination was poor for this wild North American. Last winter, we acquired some high-quality, fresh, wild-collected seed from southern Manitoba and, voilà, a fine flourish of Prairie Crocus seedlings.
The wild Prairie Crocus is paler, shorter, and even fuzzier than Pasque Flower. Wildflower enthusiasts in Manitoba start scanning south-facing, well-drained, sandy slopes in April, wanting to be the first to spot a Prairie Crocus in bloom. They often report their first up to three weeks before we get a Pasque Flower in bloom at Beaux Arbres. This gives us a clue to just how early this flower can be in a sheltered, sunny spot. Because of the subtlety of its silvery lavender colouring, Prairie Crocus is most effective grown in groups. On those dry south slopes on the Prairies, Prairie Crocus some years escapes the summer drought by going dormant, but we haven’t seen this phenomenon in our plants in the Ottawa Valley. It is good to know just how drought-tolerant Prairie Crocus can be, if you are planning a xeriscaping garden.
Prairie Crocus’s seeds are tricky to germinate, but once you are past that stage, they seem to be tough and enduring little plants, with one caveat: they are susceptible to slug predation. That suggest that, in the east, they need a dry, warm, gritty site, with perhaps a gravel mulch, certainly not any organic mulch. They are great little plants for a south-facing rock garden and perhaps for a large hypertufa trough. On the prairies, they grow in thin grassland.
Prairie Crocus grows all across the Canadian Prairies, into the northern tier of US plains states and up into Yukon and Alaska. Its range extends into north-western Ontario, but it has no claim to be native to the Ottawa Valley. We are enthusiastic about it because it extends the selection of early spring flowers for feeding newly emerged pollinators, and to cheer winter-weary gardeners, without risking the invasiveness of so many of the early spring bulbs on sale at the garden centre. (“Good for naturalizing” on the packet of Chionodoxa bulbs should be a red flag that they will escape into wild areas.)
We also have a hankering to grow all the Canadian floral emblems that we can. The Pacific Dogwood, emblem of BC, is beyond our scope, and Yukon’s Fireweed is something we hesitate to bring into the garden, although it is all over the utility corridor along the Sixth Line near our farm. Nunavut’s gorgeous Purple Saxifrage is finicky this far south, although we are game to try, if we can acquire some seed. If we are willing to accept the local Prickly Rose as a stand-in for Alberta’s Prairie Rose (possible, but too rampant in the east), the other emblems are doable, in fact we are already growing many of them.
Prairie Crocus is not, strictly, new at Beaux Arbres for Spring 2021 — sharp-eyed customers spotted the first offerings of this species last summer. We expect to have a good supply for sale this spring. Watch the website for the Availability Lists in the spring.
This cheery little flower is an under-appreciated Ottawa Valley native. Along with its early-blooming companions in the wild, such as Early Saxifrage, Prairie Smoke and Hooked-spur Violet, Early Buttercup (Ranunculus fascicularis) is a great choice to provide floral resources for newly emerged pollinators. Early Buttercup is a true spring ephemeral — the plant withers into dormancy shortly after the seeds ripen in late spring. The leaves re-emerge from the somewhat tuberous root almost as soon as the snow is gone the next spring.
Early Buttercup grows wild on only one alvar in the Ottawa Valley. It is more common on the alvars of central Ontario. Beaux Arbres’ stock of Early Buttercup was grown from seed collected in the Ottawa Valley, i.e. it is local genotype.
Early Buttercup occurs in the wild only on alvars and similar open, calcareous habitats. This gives us a clue to what it likes in the garden: full sun, sweet soil, and not being crowded by larger neighbours. Like other alvar inhabitants, it is tough, adapted to heat and cold and spring wet, and its summer dormancy allows it to endure the droughts of summer.
I am making an assumption, on this snowy day in January, that I will have Early Buttercup available in the spring of 2021. We went into the winter with a good supply of seedlings. However, I have had unexpected winter losses in the past, and I am never totally sure plants are available until I see them start to grow in the spring. I will be posting Availability Lists in the spring, as growth resumes.
I love Spikenard (Aralia racemosa), a big shrub sized perennial. The flowers are not much, small and greenish white, but the bold leaves and dark purple stems are handsome enough throughout the summer. It is in the autumn that the plant shines. The little white flowers develop into red berries that turn black when fully ripe. The little fruits grow in large showy clusters.
We grow this shade-loving forest plant on the north side of our barn, where we need something large to be in scale with the wall but where any woody shrub would get crushed in the winter by snow and ice crashing off the barn roof. The herbaceous perennial Spikenard is safely underground for the winter.
Spikenard fruit is appreciated by birds. Spikenard is fast-growing for a shade plant, and it will bear fruit in its third year from seed. If you have a shady spot and want to provide for birds, a planting of Spikenard will reward you and the birds sooner than most shade-tolerant shrubs.
Very few wildflowers for shade have large showy flowers. Producing big flowers is just not in the energy budget for a plant that survives on the scraps of sunlight that the canopy trees miss. What they lack in size, forest wildflowers make up in charm. The bright pink flowers of Panicled Tick-trefoil (Desmodium paniculatum) are a fraction of the size of those of its meadow-growing relative, Showy Tick-trefoil (D. canadense). They are, however, held upright in dainty, airy sprays, which maximizes their effect. Both of these wildflowers from the Pea family are attractive to native bees. Both also have sticky seeds, the tick-trefoils, so its is wise to site the plants carefully, away from paths where the family pooch walks.
New to me this season is American Ipecac (Gillenia stipulata). This plant of oak savannahs and rocky glades does not occur in the wild in Canada; native to Michigan and New York State down to Texas, it is adapted to drier conditions than its close relative Bowman’s Root (G. trifoliata). It has more finely divided leaves and very similar starry white flowers. Not for deep shade, but it will likely prove to be a useful addition to the roster of plants for dry, dappled or part-day shade.
Beaux Arbres will be back at Westboro Farmers’ Market on Saturday, August 10th, bringing some spectacular late-summer wildflowers.
Folks sometimes ask: Is it too late to add plants? If you can bring water to your new plants with a hose (or even a bucket from the lake, at the cottage), you can continue to plant potted nursery stock throughout the summer and early fall. The heat-loving prairie plants are in active growth right now and they are better able to make new roots than if you wait until the soil cools in the fall.
Native wildflowers are the key to having a garden than does not fade in the hot weather. All those lovely Bellflowers and Wallflowers and Paeonies of an English-style cottage garden are gorgeous in the spring, but gardens based on these non-natives struggle in the heat of summer in our continental climate.
For spectacular flower displays that thrive in heat, look to the deep-rooted flowers of the prairies: Blazing Stars, Ironweed, Culver’s Root, Prairie Mallow, Rattlesnake Master, Wild Bergamot, Showy Tick-trefoil, Cardinal Flower, and a huge diversity of tall yellow daisies. These natives also provide for native pollinators: bumblebees and other wild bees, butterflies, and hummingbirds. Later, many will also provide nutritious seeds for seed-eating birds like the vivid yellow and black Goldfinches.
Create a garden that is full of life and easy to care for by putting native plants at the centre of your garden planting.
We went to hear Kerri Weller, of the Ottawa Society of Botanical Artists, at the Nepean Horticultural Society, last Thursday evening, Ms Weller gave a quick overview of the history of botanical art and illustration in Western art. She pointed out a lovely feature of the classic plant portraits by Maria Sybila Merian from the 1700’s: the flowers were painted accompanied by their appropriate pollinators.
After a break, Kerri showed some slides of her own work, briefly illustrating how her style has developed from a more English-modern style – watercolour against a pale, unpainted background — to her current work in oil paint. She, too, likes to position, among her flowers, appropriate pollinators, of which the arbiters of botanical art correctness do not always approve. Kerri brought a few of her absolutely gorgeous canvases to the talk, including one of some yellow daisy-style flowers. Eying the yellow daisies picture, propped on an easel, for the duration of Kerri’s talk, I kept thinking, “That looks a lot like Maximilian’s Sunflower.” Sure enough, when she came to talk about that canvas, Maximilian’s Sunflower (Helianthus maximiliani) was the species she had so beautifully and realistically painted. Kerri kindly gave a word of appreciation to Beaux Arbres, for supplying the plant she painted, and praised the October-blooming Maximilian’s Sunflower for attracting a host of pollinators.
Berit Erickson dropped by last week to pick up some native plant seeds and talk to me about her demonstration pollinator garden, on a busy corner lot in the west end of Ottawa .
Working in her yard, Berit realized how interested passers-by were in her flowers. Berit herself had noticed how much more lively and inviting to bees, and butterflies and birds her city garden became when she increased the proportion of native plants. Although she had been a skilled gardener for years, the connections between native plants and wildlife had not been part of her garden lore.
What Berit saw happening in her garden, and happening relatively quickly, changed her whole approach to gardening. Berit writes, “I’m not exaggerating when I say that creating this pollinator garden was one of the best decisions I ever made and that it has changed my life.” She wanted to share her newfound understanding. She labelled the plants visible from the sidewalk, and created, printed, and set out a pamphlet “Create Your Own Pollinator Garden: you can make a difference.” More than 150 pamphlets have been picked up by passers-by. You can read more about her garden, and gain valuable practical pointers on creating your own pollinator garden, on her blog: cornerpollinatorgarden.net.
We have packaged a selection of seeds from some of our showiest flowers in time for holiday gift giving. They will be available for sale at the $100 and Under Sale of the West Carlton Art Society in Carp this Friday, Saturday, and Sunday. The seeds are sharing a table with Michael’s hand-crafted baskets. If the gardeners you know would prefer to get plants*, we have Gift Certificates available, redeemable for nursery stock and other Beaux Arbres items.
The $100 and Under Sale is rather small but full of good stuff from local artists. It is happening almost next door to the much larger Carp Christmas Market. Plan to visit both to find the locally crafted gifts you’ll want to give this Christmas.
*Hey, they are gardeners. Of course they want to get more plants.
This tall yellow wildflower loves the heat and seems to laugh at drought. Five or six feet tall on sturdy stems, Wild Senna (Senna hebecarpa) has typical pinnate Pea Family foliage but the individual flowers are more open than typical in the family. Wild Senna belongs to an early-evolved branch of the Pea family tree. The open flowers are very appealing to large bumble bees.
We have also seen hummingbirds visiting the Wild Senna flowers this year. Our hummers are foraging hard this season because so many of our cardinal flowers, the hummingbird favourite, died in the drought, and the wild Spotted Jewelweed along the seasonal stream is a fraction of its usual self.
Wild Senna does not occur in the wild in the Ottawa Valley — it hails from a little further south and occurs in southern Ontario south of Brantford. A lovely yellow butterfly whose caterpillars rely on Wild Senna — the Cloudless Sulphur — also occurs south of here. Wild Senna is an acceptable host plant for some other butterflies, including the Silver Spotted Skipper, that eat a diversity of native plants in the Pea Family, We have an abundance of Silver Spotted Skippers because we have a lot of their main host plant, Black Locust. I would never recommend planting Black Locust, which is an extremely aggressive suckering tree and thorny as all out. We are trying to beat back our Black Locusts. It is nice to know that if we ever succeed in eradicating the Black Locust (not too likely) we can still provide for the Silver Spotter Skippers with a handsome and well-behaved herbaceous flower, the Wild Senna.
Plant Wild Senna at the back of a sunny border. After the flowers finish. thin black pods remain decorative through the autumn. This plant does not need staking, fertilizing, or dividing. It consorts beautifully with tall ornamental grasses.