Tough perennials

Growers must consider many factors before investing their time and money in a new line of perennials. Greenhouse growers need plants that can finish in a reasonable time, are disease-resistant and suffer minimal shrinkage. Landscapers prefer plants that are adaptable to different soil and climatic conditions in the landscape and can stand the test of time. Finally, consumers want plants that are fairly compact, winter-hardy, drought-tolerant and even deer-resistant.

We spoke with some veteran growers to get their take on “tough perennials” — those that perform well in the greenhouse, as well as the landscape and garden, year after year.

What’s old is new

Noah Schwartz, director of growing at Neal Mast Greenhouses in Grand Rapids, Michigan, had a long list of favorites for us, but narrowed it down to four toughies, including one that is not planted as frequently, but deserving of our attention.

Epimedium, a.k.a. barrenwort: Schwartz says Epimedium is an underutilized perennial in the landscape. “It’s a great plant,” Schwartz says. “It’s drought-tolerant once established, can be grown in a fair amount of shade and flowers starting in May or June in the Upper Midwest and the Northeast.”

He says it is a little hard to find, largely because it can be expensive to propagate, which is normally done by division. However, growers are ramping up production of Epimedium, according to Schwartz, so it should become more readily available in the years to come.

“It takes a couple of years before it flowers, but the foliage is really nice-looking,” Schwartz says. “There are some that have a red or purple tint to [them], and some stay small at 12 to 14 inches, while others get up to 2 ½ feet tall.” Schwartz especially likes ‘Pink Champagne.’ He added that they’re a little expensive to start from plugs but could provide a quick turn in the fall if planted right away in the spring. Epimediums are hardy to zone 5.

Gaillardia, a.k.a. blanket flower: Schwartz had good things to say about the SpinTop series of gaillardia. He says the gaillardia stock Neal Mast Greenhouses has received has been “very consistent” and the plants have finished in eight to 10 weeks. Gaillardias are hardy to zone 4, bloom most of the summer, are drought-tolerant and add some bold colors to the landscape.

“It’s going to be a game-changer in the coming years,” Schwartz says. “They have a glossy foliage, ship well and have good shelf life.”

Ajuga tenorii: Ajuga is a tough perennial, and does really well planted in shade between flowers in a perennial or annual bed, or between stones in a pathway. This hardy plant, which requires little care after planting, just got better with a new introduction called ‘Princess Nadia.’ Schwartz says it’s a sport of ‘Chocolate Chip,’ which has dark-chocolate leaves. The new growth from ‘Princess Nadia’ is hot pink or red and eventually turns to pink, cream-colored leaves. They grow to about 6 inches tall and are hardy to zone 4.

“I think this one is going to be a good one,” Schwartz says. “It should be widely available next year.” He says it comes with a little higher royalty than others, but he thinks it will sell well in a premium pot.

Heuchera, a.k.a. coral bells: There’s always room for another heuchera, a plant that is popular with landscapers and consumers. Schwartz says Heuchera ‘Blondie’ should become a hit. This particular cultivar has light-tan colored leaves that turn a little rosy with the cooler temperatures, according to Schwartz. Expect an explosion of cream-colored flowers that last most of the summer on a compact (5-inch-tall) plant. It attracts hummingbirds and butterflies, is deer and rabbit-resistant, and can be grown in many different situations, including rock gardens, as a border plant and as a woodland plant. It can be planted in full shade to full sun and is hardy to zone 5.

Pleasing the consumer

Ultimately, plants have to perform well for the consumer. One end user perhaps we should listen to is Kathy Kangas of Kathy’s Cut Flowers in Dafter, Michigan. Kangas is a fourth-generation flower aficionado who grows perennials for the cut flowers she sells from her home and the farmers market in the chilly zone 4 region. Kangas gave us some insight into which flowers work for her year after year.

Lupinus polyphyllus, Russell Hybrids lupine mixture: These hybrid lupines come in a variety of colors, including white, pink, yellow, red and deep blue. They grow to 3 feet tall and are hardy to zone 3. They grow best in deep, rich soil that is slightly on the acidic side. Since they are a biennial, or short-lived perennial, you need to allow some to set seed for future generations. They’re a great addition for a large flower bed or meadow type planting, Kangas says.

Phlox paniculata, a.k.a. garden phlox: Kangas says ‘Bright Eyes’ is a real trooper when it comes to reliable blooming and deer resistance. Additionally, it attracts butterflies and hummingbirds. The large flowers are soft pink with a red eye. It grows to 2 feet tall and 1 ½ feet wide. Plant it in moist, but well-drained soil. It’s most impressive when it is planted massed in a flower garden or landscape and is also used for a colorful border. It’s hardy to zone 4.

Tough natives

Located in Westfield, Wisconsin, Prairie Nursery is a producer of native plants and native seed mixes. Native plants are increasingly being used by landscapers for site remediation and habitat enhancement. They are also favored by many home gardeners who wish to attract pollinators and butterflies to their property. Propagating native plants from seed often requires a stratification period. The three listed below require 30 days of stratification. Propagation and growing instructions, as well as information about where the plants are native, are available at prairienursery.com

Here are three native plants that are fairly easy to propagate from seed and do well in some tough growing situations, including clay.

Asclepias tuberosa, a.k.a. butterfly weed: Very showy orange flowers, branches out nicely. It requires light, well-drained soil and will thrive in dry soils once established. Grows to 2 feet tall. It’s hardy in zones 3 to 9.

Solidago speciosa, a.k.a. showy goldenrod: The profusion of bright golden-yellow flowers of goldenrod provide food for bees late in the season when other plants have gone to seed. This variety grows to 5 feet while staying compact. It’s hardy in zones 3 to 8.

Asclepias incarnata, a.k.a. swamp milkweed: The rosy pink flowers of swamp milkweed have a fragrant, vanilla smell to them. It provides needed food for migrating monarch and swallowtail butterflies and is deer resistant. It grows up to 4 feet tall and is hardy in zones 3 to 7.

Strong performers in the Northeast

George Africa and his wife Gail have been cultivating flowers at Vermont Flower Farm in Marshfield, Vermont, since 1983. They specialize in daylilies and hostas and have several display gardens to entice visitors to purchase their healthy root stock. Here is what George recommended, based on his many years of passionate flower gardening.

Vernonia, a.k.a. ironweed: Africa says he likes the cultivar ‘Southern Cross’ the best because it attracts pollinators and blooms later in the season. It is a shorter, more compact variety than other Vernonia species with a vase-like habit. It has attractive foliage and produces small, purple flowers that could be mistaken for asters. It reaches a height of 4 ½ feet and is semi-drought tolerant. It’s hardy in zones 4 to 9.

Helianthus, a.k.a. sunflower: ‘Lemon Queen’ is Africa’s pick when it comes to this common flower. He likes the pale-yellow flowers on the plant, which grows to about 6 feet tall. It makes a fine cut flower and attracts bumblebees. It sports creamy yellow flowers and is resistant to most plant pests, including deer and rabbits. It’s hardy in zones 4 to 9.

Neil is a horticulturist and freelance writer. greenindustrywriter.com