Oxalis Spiralis ssp. vulcanicola ‘Zinfandel’

Oxalis spiralis ssp. vulcanicola ‘Zinfandel’ (Zinfandel Volcanic Sorrel)

Bring dramatic color and year‑round interest to containers, hanging baskets, or as a low‑growing groundcover with Zinfandel™—a stunning oxalis cultivar prized for its rich plum‑purple foliage and bright yellow blooms. Zinfandel™ features deep wine‑red to nearly black shamrock‑shaped leaves that hold their intense color in part‑sun to full‑sun exposure, forming a dense, cascading mound 6–10″ tall by 10–12″ wide. Delicate five‑petaled yellow flowers appear intermittently from spring through summer, rising just above the foliage on slender stalks—no deadheading required.

Plant Profile

• Botanical Name: Oxalis spiralis ssp. vulcanicola ‘Zinfandel’
• Common Name: Zinfandel™ Volcanic Sorrel, Burgundy Shamrock
• Synonyms: Xanthoxalis vulcanicola; non‑variegated form of ‘Plum Crazy’
• Family: Oxalidaceae (Wood‑sorrel family)
• Origin & Habitat: Montane forests of El Salvador through Panama (4,600–11,000 ft elev.); thrives in organic‑rich, well‑drained forest soils
• USDA Hardiness Zones: 9–11 (perennial in frost‑free climates; tuberous, semi‑dormant to 28 °F if kept dry)
• Growth Habit: Tender, tuberous perennial; forms a low, mounding mat of semi‑succulent stems that trail or cascade 6–10″ tall and 10–12″ wide
• Foliage: Shamrock‑shaped leaflets, deep wine‑red to plum‑purple, held above the soil on slender red petioles; color intensifies in bright light
• Flowers: Five‑petaled, buttery yellow blooms with fine red throat markings; borne singly on 1–2″ pinkish stalks, intermittently from spring through summer (and often year‑round in mild climates)

Care Guide

• Light: Bright, indirect light to morning sun. In hotter climates, shield from harsh afternoon rays to prevent leaf scorch.
• Water: Keep the soil evenly moist but never water‑logged. Allow the top ¼″ of soil to dry before watering again.
• Soil: A well‑draining, organic‑rich mix (peat‑based or coco‑coir blend) ensures tubers don’t sit in water.
• Temperature: Thrives between 60–75 °F (16–24 °C); tolerant down to 28 °F when kept dry.
• Humidity: Prefers moderate humidity (40–60%); tolerates average home levels.
• Fertilizer: Feed monthly during active growth (spring–summer) with a balanced, water‑soluble fertilizer at half strength.
• Propagation: Divide tuber clusters in spring or early fall—each segment with at least one growth eye will form a new clump.
• Maintenance: Remove spent flower stalks to tidy appearance; divide clumps every 2–3 years to rejuvenate foliage color and vigor.

Uses & Styling

Ideal as a vibrant filler in mixed containers, a trailing element in hanging baskets, or a striking border plant under warm‑season shrubs. Its sterile, non‑invasive habit makes it garden‑friendly and maintenance‑free.