Kalm's St. John Wort

Hypericum Kalmianum

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Overview

Hypericum kalmianum, or Kalm's St. John's Wort, is a compact, dense shrub reaching 2-3 ft tall and wide. This hardy perennial features showy, bright yellow flowers in summer, each with a burst of prominent stamens. Its bluish-green foliage remains attractive throughout the growing season. Ideal for borders and mass plantings, it thrives in full sun to partial shade and well-drained soil. Zone 4-8 hardiness ensures wide-ranging adaptability.

Sun Full, Half, ShadeWater Extra in Summer, MediumZones 4–7Climate Temperate

Kalm's St. John Wort (Hypericum Kalmianum) — John's Wort, is a compact, dense shrub reaching 2-3 ft tall and wide

Kalm's St. John Wort (Hypericum Kalmianum) — This hardy perennial features showy, bright yellow flowers in summer, each with a burst of prominent stamens

Kalm's St. John Wort (Hypericum Kalmianum) — Its bluish-green foliage remains attractive throughout the growing season

Kalm's St. John Wort (Hypericum Kalmianum) — Ideal for borders and mass plantings, it thrives in full sun to partial shade and well-drained soil

Kalm's St. John Wort (Hypericum Kalmianum) — Zone 4-8 hardiness ensures wide-ranging adaptability

Kalm's St. John Wort (Hypericum Kalmianum) — Hypericum kalmianum, commonly known as Kalm's St

Kalm's St. John Wort (Hypericum Kalmianum) — making it an excellent choice for low hedges

Culture

Sun: Full, Half, Shade
Water: Extra in Summer, Medium
USDA zones: 4–7

Shape & size

Mature height: 2–3 Ft.
Mature width: 2–3 Ft.

Classification

Family: Hypericaceae
Climate: Temperate

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Photos (42)

Kalm's St. John Wort (Hypericum Kalmianum) — John's Wort, is a compact, dense shrub reaching 2-3 ft tall and wide

Kalm's St. John Wort (Hypericum Kalmianum) — This hardy perennial features showy, bright yellow flowers in summer, each with a burst of prominent stamens

Kalm's St. John Wort (Hypericum Kalmianum) — Its bluish-green foliage remains attractive throughout the growing season

Kalm's St. John Wort (Hypericum Kalmianum) — Ideal for borders and mass plantings, it thrives in full sun to partial shade and well-drained soil

Kalm's St. John Wort (Hypericum Kalmianum) — Zone 4-8 hardiness ensures wide-ranging adaptability

Kalm's St. John Wort (Hypericum Kalmianum) — Hypericum kalmianum, commonly known as Kalm's St

Kalm's St. John Wort (Hypericum Kalmianum) — making it an excellent choice for low hedges

Kalm's St. John Wort (Hypericum Kalmianum) — is a valuable North American native flowering shrub that adds exceptional beauty to landscape designs

Kalm's St. John Wort (Hypericum Kalmianum) — This species typically reaches 2 to 3 feet in height with a similar spread

Kalm's St. John Wort (Hypericum Kalmianum) — or as part of a mixed perennial border.<br><br>Featuring a dense

Kalm's St. John Wort (Hypericum Kalmianum) — measuring up to 1 inch across

Kalm's St. John Wort (Hypericum Kalmianum) — John's Wort is adorned with a profusion of bright yellow flowers from mid to late summer

Kalm's St. John Wort (Hypericum Kalmianum) — The foliage of this deciduous shrub consists of narrow

Kalm's St. John Wort (Hypericum Kalmianum) — showcases a burst of showy stamens

Kalm's St. John Wort (Hypericum Kalmianum) — which draw in pollinators such as bees and butterflies to the garden

Kalm's St. John Wort (Hypericum Kalmianum) — It is hardy in USDA Zones 4 through 8, demonstrating excellent cold tolerance

Kalm's St. John Wort (Hypericum Kalmianum) — This plant also exhibits resistance to a variety of undesirable conditions

Kalm's St. John Wort (Hypericum Kalmianum) — Hypericum kalmianum prefers full sun to part shade and well-drained soil

Kalm's St. John Wort (Hypericum Kalmianum) — including drought and pests

Kalm's St. John Wort (Hypericum Kalmianum) — John's Wort can serve as a charming standalone specimen or be grouped for greater impact

Kalm's St. John Wort (Hypericum Kalmianum) — making it a low-maintenance choice for the landscape.<br><br>When advising clients

Kalm's St. John Wort (Hypericum Kalmianum) — yellow flowers in the garden

Kalm's St. John Wort (Hypericum Kalmianum) — broadleaf evergreen / shrub with yellow blooms

Kalm's St. John Wort (Hypericum Kalmianum) — broadleaf evergreen / shrub for full or half or shade

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