Northwest Blooms · Perennials
Isodon longitubus
Heavenly Teacost
- Family
- Lamiaceae
- Height
- 36 to 48 inches
- Width
- 18 to 24 inches
- Flower color
- Violet to lavender tubular flowers
- Foliage color
- Bright green leaves with serrated edges
- Bloom time
- Late summer to early fall
- Light
- Partial shade to full shade
- Water
- Moderate
- Maintenance
- Low; occasional pruning after flowering for shape, and mulching to retain soil moisture
- Growing zone
- Zones 5-8
- Wildlife
- Attracts pollinators, including bees and butterflies
About this plant
Isodon longitubus is a late-blooming perennial that showcases tubular flowers in shades of pale violet to lavender-blue, arranged along arching stems. The blooms appear in clusters from late summer into autumn, adding a subtle charm to the garden during the transition from warm to cooler weather. The flowers' elegant, elongated shape and soft coloration make them a delicate and graceful addition to the landscape.
Native to Japan, Isodon longitubus thrives in woodland and shaded environments, where its understated beauty complements other shade-loving plants. Its ability to bloom late in the season makes it an excellent choice for extending garden interest into autumn.
Works well in
Borders · Shade Gardens · Woodland Gardens · Pollinator Gardens · Cut Flower Gardens
Companion plants
Siberian bugloss · Sweet woodruff · Foamflowers · Epimediums · Hostas · Bleeding hearts
Design tip
Late flowers extend the season, so set it behind or beside plants that finish in midsummer. Keep it out of hot afternoon sun and layer it with woodland companions for a full, settled look.
Where to see it
This plant can be seen in the perennial border at the Bellevue Botanical Garden.
