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How to Grow Centranthus — Red Valerian

Red valerian Centranthus

Centranthus ruber — commonly called red valerian — is an upright perennial with white, pink, or red flowers. It is sometimes seen along roadsides but is a good fit for cottage gardens.

Centranthus forms bushy clumps with upright stems to 3 feet tall. Small, dusty crimson or rose-pink flowers appear in dense terminal clusters. Blooms are long-lasting.

Centranthus readily self sows; in some regions, it is considered a weed. Centranthus easily grows in poor dry soils and needs little care. The bloom time can be extended by cutting off old flowering stems.

Centranthus ruber

Get to Know Centranthus

  • Plant type: Perennial, lives 3 to 5 years
  • Growing Zones and range: 4-8; best in cool-summer area
  • Hardiness: Hardy to -25°F/-32C°
  • Height and width: 1 to 3 feet tall (30-90cm), 1 to 2 feet wide
  • Foliage: Bushy clumps of stems to 3 feet high with pointed 4-inch grayish blue-green leaves
  • Flowers: Small flowers on domed clusters.
  • Flower colors: Red, pink, white
  • Uses: Use in borders or cottage garden; attracts butterflies
  • Bloom time: Spring through early summer
  • Common name: Red valerian, Jupiter’s beard
  • Botanical name: Centhranthus ruber
  • Family: Valerianaceae
  • Origin: Southern Europe, the Mediterranean, Northwest Africa

Where to Plant Centranthus

  • Plant Centranthus in full sun.
  • Centranthus will grow in poor, average, and alkaline soil with good drainage. It does not do well in soil that is too rich.

Centranthus Uses and Companions.

  • Plant Centranthus in cottage gardens and rock gardens or in a border.
  • Good garden companions for Centranthus include Aster frikartii, Chrysanthemum superbum, Hemerocallis, bearded Iris, Nepeta.
  • Centranthus may be difficult to match with most pinks and reds; it is best with blue, white, and yellow.
Red Valerian (Centranthus ruber)
Red Valerian (Centranthus ruber)

When to Plant Centranthus

  • Set Centranthus outdoors in spring after the last frost has passed.
  • Sow seed in spring or early summer in evenly prepared soil.

Planting and Spacing

  • Space Centranthus 1 to 2 feet apart.
  • Seed readily self sows; sow seed 1/8 inch deep in evenly prepared soil.

How to Water and Feed Centranthus

  • Keep the soil evenly moist; do not let it dry out especially when plants are young. Centranthus is drought tolerant once established.
  • Centranthus does not need to be fertilized.

Centranthus Care

  • Mulch Centranthuswith organic planting mix to conserve soil moisture.
  • Trim away spent blooms. Red valerian will self-seed if blooms are left to drop.
  • Plants may become floppy after blooming; shear them back to promote compact growth.
  • Centranthus has no serious pests or disease.
Centranthus ruber or red valerian, which is called jupiter beard
Centranthus ruber or red valerian, which is called jupiter beard

Centranthus Propagation

  • Centranthus can self-sow prolifically.
  • Centrathus seeds germinate in 21 to 30 days at 65° to 70°F (18°-20°C).
  • Remove basal shoots and plant them like cuttings.

Centranthus Varieties to Grow

  • Centranthus ruber var. albus has white flowers.
  • C. ruber var. coccineus has deep red flowers.
  • C. roseus has deep rose flowers.

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