Annuals, Perennials, Flowers
Campanulas are most often recognized by their blue or white flowers (they also come in pink, violet, and lavender). Usually, flower stalks rise above basal leaf rosettes. The perennial species tend to spread from the root; width depends mainly on the vigor of their rootstocks and the time they have been in one spot. Flowers are generally bell shaped, though some are star shaped, cupped, or round and flat. Bloom comes at some time from spring to fall, depending on the species. Native throughout the Northern Hemisphere; those featured here come mostly from southern Europe, Turkey, the Caucasus, and northern Asia.
Uses are as varied as the plants. Gemlike miniatures deserve special settings—close-up situations in rock gardens, niches in dry walls, raised beds, or containers. Trailing kinds are ideal for hanging pots or baskets and wall crevices; vigorous, spreading growers serve well as groundcovers. Upright growers are valuable in borders, for cutting, and occasionally in containers.
Campanulas grow best in good, well-drained soil. Most species are easy to grow from seeds sown in spring or early summer. Set transplants out in fall for bloom the following year. Also may be increased by divisions or cuttings. Divide clumps in fall every 3 or 4 years; some may need yearly division. Some species seed freely, and a few have invasive tendencies; may be difficult to remove when entwined with roots of shrubs, trees, or other perennials. For these species, choose sites carefully. Some campanulas are attractive to slugs and snails. Watch for spider mites in hot, dry weather.
Compact, spreading, leafy tufts, to 6 in. tall. Flower stems are upright, branching; usually about 8 in. tall, but may rise 1–1 1/2 ft. Foliage is smooth, bright green, with wavy, toothed edges, 1–1 1/2 in. long. Basal leaves are round, often drying up before bloom; stem leaves are oval to triangular. Flowers are profuse, upward facing, bell or cup shaped, 1–2 in.; light blue, violet, or white. Late spring bloom.
Upright, with erect side branches to 1–2 ft. Basal leaves are broad, wavy edged; stem leaves are broad, toothed. Both are somewhat hairy. Flowers are narrow, 1-in. bells, flaring at the mouth; in violet, blue, white; and tightly clustered at tops of stems. Spring through summer blooming.Campanula isophylla
Trailing or hanging soft stems to 2 ft. long, becoming woody at base. Round or heart shaped, light green, toothed, leaves, 1–1 1/2 in. long and wide. Loose clusters of upward-facing, 1-in.-wide stars in white or light blue, depending on variety. Blooms in late summer, fall (nearly year-round in mildest climates).
Good in hanging baskets, wall pots, top of walls, or rock gardens in filtered shade. Choice groundcover for small areas on slopes in mild-winter climates. Indoor/outdoor plant where winters are cold.
Sturdy, hairy, leafy, with erect stems 2 1/2–4 ft. tall, 1 ft. wide. Lance-shaped, wavy-edged basal leaves are 6–10 in. long; stem leaves are smaller (3–5 in.). Bell shaped or urn shaped, 1–2 in. flowers are single or double, held upright in long, loose, open clusters. Purple, violet, blue, lavender, pink, or white, depending on variety. Late spring or early summer blooming.
Sow seed in late spring for bloom the following year, or set out nursery plants 15–18 in. apart. Good for cutting.
Strong-growing, slender, erect stems 2–3 ft. tall. Plants leafy at base. Basal leaves smooth-edged, green, 4–8 in. long. Stem leaves 2–4 in. long, shaped like leaves of peach tree. Flowers are open, cup-shaped, about 1 in. across, and held erect by short side shoots on sturdy stems. Blue, pink, or white, depending on variety. ‘Telham Beauty’, an old favorite, has 3-in. blue flowers. Summer blooming.
Choice plant for borders. Easy to grow from seed sown in late spring.Campanula portenschlagiana
Low, leafy, mounding or trailing mats 4–6 in. high. Semierect, branching flower stems to 8 in. high. Tiny leaves are roundish, heart-shaped, deep green with deeply toothed, slightly wavy edges. Flowers are shaped like flaring bells, violet blue or grayish white, to 1 in. long; several to each stem. Blooms late spring into summer, sometimes again in fall.
Fine plant for edging or as small-scale groundcover. Spreads moderately fast and is sturdy, permanent, and noninvasive. Easily increased by dividing.
Spreading, mounding, leafy clump to 8 in. high. Branching, semi-upright flower stems to 1 ft. or more. Elongated heart shape, irregularly toothed, slightly hairy leaves are 1–3 1/2 in. long and 3/4–3 in. wide. Star-shaped, 1/2–1-in.-wide blooms in blue-lilac, lavender, or grayish white. Spring to early summer blooming.
Very vigorous. Good for shaded border near pools or in partially shaded rock gardens with fuchsias and begonias. Good groundcover for small area. Needs little water.
Flat basal rosette spreads rapidly by underground runners. Wiry 1–1 1/2-ft. flower stems arch over at the tip. Foliage is dark green, toothed, 4–5 in. across, heart shaped; leaves are narrower on upper stems. Flowers are 2–2 1/2 in. long, tubular, waxy, and shaped like drooping bells, in shades from cream through pink to deep maroon. The inside of the flower is paler and spotted with crimson. Blooms late spring to early summer, with some scattered bloom until frost.
Forms a dense, weed-suppressing mat between shrubs but is too invasive for mixed borders. Some dwarf forms exist.
Slowly spreading clump, 2–3 in. high. Slender, upright flower stems, some branched, 6–18 in. tall. Foliage is green or gray. Basal leaves are roundish, long stalked, 1 in.; may dry before bloom. Stem leaves are grasslike, 2–3 in. Flowers are broad, bell-shaped bright blue, lavender, or white; 1 in. long. One or a few nodding in open clusters.Campanula takesimana
Native to much of the northern hemisphere. Flat, basal rosette spreads vigorously by underground runners, forms dense, weed-suppressing mat of rounded glossy leaves. Flowers are 2-in., pendant, pale lilac bells, spotted maroon inside. Early summer.
Sprawling plants that bloom over a long season, bearing phlox-like clusters of blue or white flowers a...
Clusters of lilac flowers on stems 2 1/2–5 ft. tall. Resembles A. giganteum but with sm...