Arrowleaf balsamroot

Sun

Full sun; tolerates light shade but flowers best in open sites.

Water

Low once established. Provide occasional deep watering during establishment, then allow the soil to dry; avoid routine summer irrigation.

Soil

Well-drained sandy, gravelly or loamy soil, preferably with a deep rooting layer. Avoid waterlogged ground and heavily enriched beds.

Height

1-3 ft (0.3-0.9 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Spring to early summer, depending on elevation and climate; bright yellow flowers with yellow centres.

Foliage

Large, arrow-shaped basal leaves covered with fine hairs, giving them a grey-green to silvery appearance. Leaves often dry back during summer drought.

Growth

Slow; seed-grown plants commonly take several years to flower.

Care needed

Low

• Pollinators
• Drought tolerant
• Cold hardy
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.2 ft (0.36 m)

3. After 2 years

   1.4 ft (0.42 m)

4. After 3 years

   1.6 ft (0.49 m)

5. After 5 years

   2 ft (0.6 m)

   full size

About 5 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Native to

Canada

Growth rate

Slow

• Choose a permanent position with full sun and excellent drainage.
• Plant young, container-grown plants without disturbing their taproots.
• Water young plants deeply but infrequently, letting the soil dry between waterings.
• Do not feed routinely; avoid rich compost and high-nitrogen fertilisers.
• Keep weeds away from slow-growing seedlings and leave the crown free of damp organic mulch.
• Do not divide established clumps or water dormant plants to force fresh summer growth.

Pruning. Remove dry flower stalks after seed has ripened, or leave them for seed-eating wildlife. Cut away dead leaves once fully brown, keeping clear of the crown.

Autumn

Sow fresh seed outdoors in a protected seedbed or deep pots so it receives natural winter chilling.

Winter

Check that pots and planting sites drain freely; prevent standing water around crowns.

Early spring

Plant young nursery stock before strong growth begins, keeping the rootball intact.

Spring

Remove competing weeds and protect emerging seedlings from slugs.

Early summer

Leave some flower heads to mature if you want seed or food for wildlife.

Summer

Allow established plants to become dormant as the soil dries; remove fully dead foliage if desired.

• Plant in loose groups among drought-tolerant bunchgrasses for a western meadow effect.
• Use on sunny, well-drained banks where its broad leaves contrast with fine grasses.
• Combine with penstemons and buckwheats in a dry pollinator border.
• Place in a gravel garden with later-flowering neighbours that soften the gaps left by summer dormancy.

Garden styles it suits: Native meadow, Wildflower, Pollinator garden, Desert / xeriscape, Dry gravel garden and Mountain lodge.

Plant it with: Bluebunch wheatgrass, Idaho fescue, Prairie junegrass, Sulphur buckwheat, Showy penstemon and Yarrow.

Wildlife: Flowers provide pollen and nectar for native bees and other insects, and the seeds feed birds and small mammals. Deer and other grazing animals may browse the foliage and flowers.

• Crown or root rot in wet soil: improve drainage or move young plants to a raised, gritty site; avoid summer irrigation once established.
• Slugs and snails eating seedlings: inspect young growth and use barriers or a labelled iron-phosphate bait where needed.
• Poor seed germination: use fresh seed and provide a prolonged period of cold, moist conditions before spring warmth.
• Failure after transplanting or division: use young plants with intact roots; established taproots resent disturbance.

Not known to be toxic to people, cats, dogs or horses. Roots, seeds and young shoots have traditional food uses, but pet-specific safety information is limited; do not treat this as advice to eat garden plants.

• Puget balsamroot (Balsamorhiza deltoidea)

  Usually has greener, less densely hairy leaves with broadly triangular blades and heart-shaped bases; arrowleaf balsamroot has more distinctly arrow-shaped, silvery leaves.

• Hooker's balsamroot (Balsamorhiza hookeri)

  Its leaves are deeply lobed or divided, unlike the broad, undivided leaves of arrowleaf balsamroot.

• Mule's ears (Wyethia amplexicaulis)

  Has greener, mostly hairless leaves, including conspicuous stem leaves that clasp the flowering stems; arrowleaf balsamroot carries most of its silvery leaves at ground level.

Balsamorhiza means 'balsam root', referring to the resinous root, while sagittata means 'arrow-shaped', describing the leaves.

Propagation. Grow from seed, preferably sown outdoors in autumn. Seed generally needs cold, moist stratification, and germination can be uneven. Use deep containers and plant out while young; division is unsuitable because of the large taproot.

Accepted botanical name

Wyethia sagittata Balsamorhiza sagittata is an older name for Wyethia sagittata.

Native range

Alberta, Arizona, British Columbia, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota and Utah.

Measured

Soil pH 6.5 to 8. Average height 51 cm.

Sources: GBIF (CC BY 4.0) and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.