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How to Grow Red Valerian — Centranthus

ByStephen Albert

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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 Centranthus with 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 diseases.
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.

Stephen Albert is a horticulturist, master gardener, and certified nurseryman who has taught at the University of California for more than 25 years. He holds graduate degrees from the University of California and the University of Iowa. His books include Vegetable Garden Grower’s Guide, Vegetable Garden Almanac & Planner, Tomato Grower’s Answer Book, and Kitchen Garden Grower’s Guide. His Vegetable Garden Grower’s Masterclass is available online. Harvesttotable.com has more than 10 million visitors each year.

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