Watermelon Berry (Streptopus amplexifolius) — also known as Claspleaf Twistedstalk or Wild Cucumber — is a unique, hardy woodland perennial native to cool, moist forests of North America and Eurasia. Its delicate, arching stems produce small, bell-shaped flowers that ripen into bright red berries with a mild, refreshing flavor reminiscent of watermelon and cucumber.

This shade-loving plant thrives in moist, humus-rich soil and makes a wonderful addition to native gardens, woodland landscapes, or shaded wildflower collections. While rare in cultivation, it’s a fascinating edible and ornamental species for gardeners who enjoy growing something truly unique.

Features

• Rare Native Species: Beautiful woodland plant rarely found in home gardens.
• Edible Berries: Sweet, cucumber-like fruit can be eaten raw or used in jams.
• Shade-Loving Perennial: Ideal for forest gardens and shady areas.
• Ornamental Appeal: Graceful stems and bell-like flowers add woodland charm.
• Cold Hardy: Thrives in cooler climates and mountain regions.

Specifications

• Common Name: Watermelon Berry, Claspleaf Twistedstalk, Wild Cucumber
• Scientific Name: Streptopus amplexifolius
• Plant Type: Perennial herb
• USDA Zones: 3 – 8
• Mature Height: 12 – 36 in (30 – 90 cm)
• Spread: 12 – 18 in (30 – 45 cm)
• Light Requirements: Partial to full shade
• Soil Type: Moist, rich, well-draining woodland soil
• Soil pH: 5.5 – 7.0
• Watering: Consistently moist; avoid drying out
• Temperature Range: Prefers cool to mild climates
• Germination Time: 30 – 90 days (may require cold stratification)
• Bloom Time: Late spring to early summer
• Fruit Time: Mid to late summer
• GMO Status: 100% Non-GMO
• Origin: Native to North America and northern Eurasia

Planting Guide

• Stratify Seeds: Cold stratify for 60–90 days in moist sand or peat at 35–40°F (2–4°C).
• Sow Depth: ¼ inch deep in rich, moist soil.
• Light: Place in partial or full shade; avoid direct, hot sunlight.
• Temperature: Ideal germination temperature 55–65°F (13–18°C).
• Watering: Keep soil evenly moist but not waterlogged.
• Transplanting: Move seedlings outdoors after frost danger has passed.
• Maintenance: Mulch to retain moisture and suppress weeds.