Many tough-as-nails perennials are passed along from gardener to gardener, and that is how I received my first division of ‘Gerald Darby’ iris (Iris robusta ‘Gerald Darby’, Zones 4–9). In early spring, the new shoots emerge a dark midnight blue, maturing to green. Dark purple 4-foot-tall stems rise above the foliage, topped with violet-purple flowers in late spring. After flowering, the foliage continues to grow into a lush, attractive mound 18 to 30 inches wide. This iris will thrive in wet soils and heavy clay, but will not tolerate dry soil.

Finding plants for partial shade can be tricky: too much sun and they will burn; too little and they will not bloom. But European wood anemone (Anemone nemorosa, Zones 5–9) never fails me. This charming low spreader can eventually form an impressive clump 3 feet wide and 6 inches tall, dotted with showy blooms in early to mid-spring. The typical flower is clear lavender-blue, but white and pink selections are available as well as a few choice doubles. The delicately cut foliage sprouts in late winter, then dies away by early summer, making way for the late-season perennials. It is the perfect foil for spring bulbs. European wood anemone adapts to a wide range of soils, including sand and clay, but prefers a well-drained location.

Lily-of-the-valley (Convallaria majalis, Zones 3–8) is a beautiful and fragrant plant, but in its natural form can be a rampaging thug in the garden. I prefer to use the much less aggressive golden-leaved selection, ‘Fernwood’s Golden Slippers’. In early spring, acid-yellow leaves emerge, creating a brilliant glow in the garden. Soon after, the classic, fragrant white flowers dance among the leaves. Allow it to ramble between other later-growing perennials and shrubs. This will protect the golden leaves from burning in areas with very hot summers.

Distinctive shade lovers brighten the deepest shadows

Of the hundreds of hosta cultivars, my favorite is ‘Sagae’ (Hosta ‘Sagae’, Zones 3–9). When I saw it for the first time, I was consumed with plant lust, and it quickly rose to number one on my want list. The slightly wavy leaves are a cool blue-green edged in butter yellow; deeply impressed veins give it a somewhat corrugated appearance. It will grow 24 to 30 inches tall and 4 feet wide with an upright mounded habit. It has excellent substance, that elusive quality that hosta lovers seek, and has shown resistance (but not immunity) to slug and snail damage.

The eastern U.S. native baneberry (Actaea pachypoda, Zones 3–8), commonly called doll’s eyes, grows 3 feet tall and wide and is a great addition to the late summer garden. The dark green leaves are topped with clusters of pure white berries on bright red stems. These long-lasting berries are quite poisonous but are so bitter that even most wildlife will avoid eating them.

Few perennials are more unusual than the hardy begonia (Begonia grandis, Zones 6–9). It is slow to emerge in spring but grows quickly in the summer heat with large dark green, oval-shaped leaves often marked with burgundy on the undersides. The stems will grow 2 to 3 feet tall with clusters of hanging pink blooms from midsummer to the early days of autumn.

Using tough plants like these gives peace of mind that the perennial beds will always look full, no matter how you may be swayed to try something new.

What makes a tough-as-nails perennial?

When looking for tough-as-nails perennials, I keep a list of criteria in mind. First, I consider the basics.

• The plant should be cold hardy and heat tolerant for your area. In difficult or exposed sites, I look for plants with hardiness ratings at least one zone lower than typical.
• Look for long-lived perennials. The best choices will live five years or more without needing to be divided or replaced.
• Disease and pest resistance are worth researching. Talk with other gardeners or local master gardeners about possible problems.

Second, consider maintenance. The best tough-as-nails perennials require minimal care with no special treatments.

• Some degree of drought tolerance is essential. Once established, these performers should not need to be watered more than once every two to three weeks.
• The very best choices will look great with almost no input from you. The plants should tolerate a wide range of soil types and conditions, require no pinching or staking, and look good even when they aren’t flowering.

Sources

• Bluestone Perennials, Madison, Ohio; 800-852-5243; bluestoneperennials.com
• Klehm’s Song Sparrow Farm and Nursery, Avalon, Wis.; 608-883-2356; songsparrow.com
• Plant Delights Nursery, Raleigh, N.C.; 919-772-4794; plantdelights.com