How to Grow Aruncus — Goat’s Beard

Aruncu dioicus
Blooming Aruncus dioicus

Aruncus–commonly called goat’s beard–is a shrub-like woodland plant with showy, plume-like spikes of tiny, cream-colored foliage. It looks very much like astilbe. Aruncus is easy to grow and makes a good background plant in beds and borders. A single plant may be used as an accent.

Grow Goat’s Beard in part to full shade in humus-rich soil. Goat’s beard does not grow well in hot, humid regions. Aruncus thrive in moist soil and is a good plant to grow near ponds.

Aruncus is a genus member of the Rose family.

Aruncus dioicus commonly called goatsbeard
Aruncus dioicus commonly called goatsbeard

Get to know Aruncus

  • Plant type: Perennial
  • Growing Zones and range: Zones 4 to 9
  • Hardiness: Hardy to -35°F (-37°C); plants will struggle in hot and humid regions; plant tolerate cold.
  • Height and width: 3 to 6 feet (90-180cm) tall; 3 to 5 feet wide
  • Foliage: Shrub-like plant with large three-lobed leaves and airy plumes of flowers.
  • Flowers: Huge white feathery panicles of flowers with small petals; flowers are followed by blackberries. Male and female flowers are borne on separate plants.
  • Flower color: Creamy white
  • Bloom time: Early summer
  • Uses: Good choice for woodland gardens; berries provide winter interest in the garden. Attracts birds, butterflies, and other pollinators.
  • Garden companions: Plant with ferns, wildflowers, hostas in lightly shaded woodland garden; combine with other perennials in beds and borders.
  • Common name: Goatsbeard
  • Botanical name: Aruncus
  • Family: Rosaceae
  • Origin: Mountainous areas in the Northern Hemisphere

Where to plant Aruncus

  • Plant Aruncus in full sun in Zones 3-4; needs shade in Zones 5-7.
  • Grow Aruncus in humus-rich, moist, deep soil.
  • Soil pH: Neutral to slightly acid soil–6.5.

Aruncus uses and companions

  • Grow Arunucs in a perennial border, rock garden, or woodland garden.
  • Plant Aruncus in clusters along a wood edge, along streams, and in other natural settings.
  • Good companions for Aruncus are Bergenia, Hosta, Siberian Iris, Ligularia.
Aruncus dioicus
Aruncus dioicus

When to plant Aruncus

  • Set young plants in the garden in spring. Established plants have extensive roots and can be difficult to transplant.
  • Start seeds indoors in spring in flats or six-packs; cover seeds with 1/8 inch of soil or finely milled vermiculite. Keep seeds at 40° to 60°F (4.4°-15.6°C) until they germinate.
  • Germination takes 30 to 60 days. Transplant seedlings to the garden when they are 3 or more inches tall.
  • Sow seeds outdoors after the danger of frost has passed in spring. Also, sow seeds in summer or fall. Sow seeds in evenly prepared soil.
Aruncus dioicus
Aruncus dioicus

Planting and spacing Aruncus

  • Space Aruncus plants 4 to 6 feet (1.2-1.8m) apart.
  • Sow seed 1/8 inch deep in evenly prepared soil.

How to water and feed Aruncus

  • Keep the soil evenly moist; if the soil dries, the plant will decline.
  • Fertilize Aruncus with a side dressing of all-purpose fertilizer every three weeks or add a slow-release fertilizer to the soil in spring.

Aruncus care

  • Work aged compost into the soil ahead of planting goat’s beard. Side dress established plants with aged compost or organic planting mix.
  • Mulch around plants to conserve soil moisture.
  • Protect plants in winter by mulching with 2 inches of chopped leaves; remove mulch in spring when new growth begins.
  • Aruncus is rabbit and deer-resistant.
  • Aruncus has no serious pests or diseases.
Aruncus at the back of a perennial border
Aruncus at the back of a perennial border

Aruncus propagation

  • Divide Aruncus in spring or autumn every 2 or 3 years. However, the roots are large and may be difficult to cut. Best to divide Aruncus only to revitalize the clump.
  • Sow seed in summer outdoors.
  • Arunucs seed will germinate in 28 to 35 days at 55° to 65°F (13°-18°C).

Aruncus varieties to grow

  • Aruncus aethusifolius: Perennials make foot tall mounds with white flower plumes to 16 inches (40cm) long; use in rock gardens and as edging.
  • A. dioicus (A. sylvester): Perennial grows to 6 feet (1.8m) tall with foam white flowers in much-branched clusters; this is the main garden type; cultivars include ‘Child of Two Worlds’ is compact to 4 feet (1.2m), ‘Kneiffii’ grows to 3 feet (.9m) and has deeply cut ruffled leaves.

Aruncus dioicus (A. Sylvester) – Goats Beard

Aruncus dioicus bears foot-long, feathery plumes of creamy white flowers on tall stalks in early summer. Plants are male or female; males produce showy stamens that last through summer. Leaves are light green and finely dissected, forming handsome clumps beneath the flowers.

  • Size: Foliage mounds to 3 feet tall, 3 to 5 feet wide; flower stalks to 6 feet tall.
  • Light: Half to light shade in Zones 57; full sun in zones 3-4 if constantly moist.
  • Soil and moisture: Rich, moist, deep soil, high in organic matter, abundant water.
  • Planting and propagation: Plant container grown or bare-root plants in spring, spacing 4 to 5 feet apart. Division not necessary but can be done with difficulty in spring by lifting roots and cutting into divisions with one bud eye.
  • Special care: If too dry or in too much sun, leaf edges turn brown.
  • Pests and diseases: Generally pest free.
  • Climate: Zones 3-8, difficult in Zones 7-8.
  • Cultivars and similar species: ‘Kneiffii,’ 3 feet tall, more finely cut leaves. A. aetbusifolius (dwarf goat’s beard): flower 3 to 4 inches tall, mounds of finely cut leaves attain height of 8 inches to 1 foot. Hybrids of the two species are intermediate in size.
  • Garden use: Plant in clusters along wood-land edge, along streams or in other naturalistic settings; also works well in borders if kept moist.

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