For drop-dead gorgeous flowering plants, nothing compares to a delphinium. In June and July, even the simplest garden feels elegant if it includes a delphinium’s elegant spires of bloomsusually blue, but sometimes pink, white, yellow or even orange.
“Delphiniums are incredibly impressive. They present themselves very regally,” says Craig Bergmann, the Wilmette landscape designer who also owns a nursery in Winthrop Harbor, Craig Bergmann’s Country Gardens. Bergmann is so taken with delphiniums that he imports seed from England, via that country’s Delphinium Society, so he can grow extra-fabulous varieties for the gardens of his North Shore clientele. “They’re one of the few true blue flowers,” he says, “and they provide spectacular architecture in the garden.”
Kathy Scopelliti, a designer at Anthony Scopelliti Landscaping in Winnetka, likes delphiniums for their uprightness as well as their color. “They’re a great plant for getting height without taking up a lot of width,” she says. “They stay where they’re put and don’t take room from another plant.”
Professionals like Scopelliti and Bergmann aren’t the only ones with a thing for delphiniums. Many gardeners get smitten. But as with many loves, delphiniums often invite disappointmentat least in the Chicago area, where heavy clay soils aren’t hospitable.
“You see delphiniums in northern Wisconsin where the soil is looser and they can root better, and they look beautiful. But down here it’s hard to be successful with them,” says Carrie Block, perennials manager at Sid’s Greenhouse, Garden Center & Landscape in Palos Hills. Delphiniums like full sun and richly fertile soil. But even given those two conditions they often refuse to come back for a second year, she notes.
Unfortunately, delphiniums still are priced like perennialsbecause most nurseries sell second-year plants that are sure to bloomso it’s essential to maximize the return on your investment. Look for these delphiniums, preferred by local horticulturists:
– Delphinium `Bellamosum’ is a dark blue member of the Belladonas, the group of delphinium varieties with a looser, airier flower spire than the classic tightly packed look. Scopelliti likes it for the rich contrast it sets up with white flowers nearby. Other, lighter Belladonnas, such as the pale blue `Cliveden Beauty,’ are “are nice to have for a sunny spot when all the shady areas are full of dark colors,” she says. `Picolo’ is another pretty blue.
– Delphinium `Blue Bird’ and `Blue Jay’ are Bergmann’s picks for “the most brilliant blue of the blue delphiniums. Not purple. Blue.” Both belong to the Pacific Hybrids group, which means they have the tightly packed look and they’re grownand therefore often pricedas annuals. `Blue Jay’ has a black “bee,” or center; `Blue Bird’ has a white one. They can reach 5 feet in height.
– Delphinium `Butterfly Compact’ is a favorite of Linda Walker, a horticulturist at Schwarz Nursery & Garden Center in Addison, because of what she calls its “ultramarine blue flowers, the most stunning blue of any flower.” It’s one of the tight-spired Elatum group of varieties. And it’s small, growing to around 1 foot high. It blooms May to June.
– Delphinium `Magic Fountain’ is a line that provides the Elatum look in an array of colors, “sky blue to lilac pink,” Walker says. They come in assorted heights.
Growing tips
Craig Bergmann recommends fertilizing delphiniums every 2 1/2 to 3 weeks from April through August. His other tips are:
– Don’t plant delphiniums when they are at their showiest in the garden center, in full bloom in June or July, but in April. “They like cool soil temperatures to deep-root,” Bergmann says.
– When planting in April, dig a hole deep enough to hold not just the root ball but also the stem and the two lowest leaf nodes. “What it does is provide insulation for winter temperatures and stability for the plant as it grows.”
– Put them in the best-draining soil you have or can create, by adding sand and compost to the planting area. “If you can grow astilbes in it, you can’t grow delphiniums in it,” Bergmann says.
– Largely because of our soils, Bergmann and others say that although they are perennials, delphiniums are best thought of as annuals here. “We still lose an average of 50 percent (each year),” Bergmann says. “If they come back, it’s a gift.”
— Dennis Rodkin
Where to buy
In addition to the nurseries mentioned in the story, here are some mail-order sources:
– Spring Hill Nurseries, 6523 N. Galena Rd., Peoria, IL 61632, 888-238-8118, or www.myseasons.com.
– White Flower Farms, P.O. Box 50, Route 63, Litchfield, CT 06759-0050; 800-503-9624; www.whiteflowerfarm.com.
– Park Seed Co., 1 Parkton Ave., Greenwood, SC 29647-0001; 800-845-3369; www.parkseed.com.
