Northwest Blooms · Groundcovers
Hypericum calycinum
St. John's Wort
- Family
- Hypericaceae
- Height
- 12 to 18 inches
- Width
- 15 to 24 inches
- Flower color
- Bright golden yellow
- Foliage color
- Blue-green
- Bloom time
- May to July
- Light
- Full sun to partial shade
- Water
- Low; drought-tolerant
- Maintenance
- Low; mow to the ground every year or two in winter or early spring
- Growing zone
- USDA Zones 5 to 9
- Wildlife
- Attracts bees
About this plant
Hypericum calycinum, commonly known as St. John's wort, is a low-growing perennial native to Europe and Asia. It blooms profusely in summer, typically from May to July, producing large, showy blossoms with numerous stamens that give it a fluffy, star-like appearance. The bright yellow flowers are a standout in gardens, especially against the dark green foliage.
This cultivar is known for its colorful blooms and ability to thrive in a variety of conditions, making it a reliable choice for filling in garden beds or slopes. The plant's thick, leathery leaves complement its bold flowers and contribute to its overall dense, bushy growth. Its resilience and ability to attract pollinators, including bees and butterflies, make it a great addition to both ornamental and wildlife-friendly gardens.
Works well in
Slopes & Banks · Borders · Containers · Rock Gardens
Companion plants
Lavender · Creeping phlox · Catmints · Coneflowers · Ninebark · Feather reed grasses
Design tip
Plant broad sweeps of this vigorous groundcover to stabilize slopes and soften the edges of sunny borders. Pair it with upright flowering perennials, ornamental grasses, and contrasting shrubs to create bold layers of color, texture, and natural rhythm.
