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Trachystemon orientalis
giant borage
Southeastern Europe and western Asia — Turkey, Caucasus, Bulgaria, and Georgia; moist deciduous woodlands and stream banks
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Overview
Trachystemon orientalis is giant borage (Abraham-Isaac-Jacob), a spreading deciduous perennial growing 18-24 inches (45-60 cm) tall and 24-48 inches (60-120 cm) wide. Violet-blue flowers 0.5 inch (1.3 cm) with reflexed petals and white-fringed corolla tube in coiled cymes on bare stems in February-March (4 weeks) — the flowers appear before the leaves. Enormous broadly heart-shaped rough-hairy leaves 10-16 inches (25-40 cm) expand after bloom to form a dense weed-suppressing canopy. In Boraginaceae. Orientalis = from the east. Native to southeastern Europe and western Asia. Spreads by thick rhizomes. Tolerates dry shade under established trees once the rhizome system is established (2-3 years of consistent moisture first). The aggressive rhizomatous spread and the very large leaf size require ample space — this is the primary spatial limitation. The leaves collapse untidily after the first hard frost. Tolerates clay, poor soil, and root competition. Deer-resistant. Non-toxic. Zones 5-9. Part shade to full shade. Growth rate is fast (via rhizomes).
Native Range
Native to southeastern Europe and western Asia — Turkey, Caucasus, Bulgaria, and Georgia. Found in moist deciduous woodlands and stream banks.Suggested Uses
Grown as a weed-suppressing shade ground cover under established trees, along shaded banks, and in wild areas, spaced 24-48 inches (60-120 cm). Tolerates dry shade and root competition. Pre-foliar bloom. Non-toxic. Zones 5-9.How to Identify
Appearance
Size & Dimensions
Height1'6" - 2'
Width/Spread2' - 4'
Reaches mature size in approximately 3 years
Bloom Information
Late winter to early spring (February-March). Violet-blue flowers 0.5 inch (1.3 cm) with reflexed petals in coiled cymes on bare stems. Pre-foliar (before leaves). 4 weeks. Bee-visited.Detailed Descriptions
Flower Description
Violet-blue, small, 0.5 inch (1.3 cm), with reflexed petals and a white-fringed corolla tube; in coiled cymes (scorpioid) on bare stems in late winter — the flowers appear before the leavesFoliage Description
Broadly heart-shaped, 10-16 inches (25-40 cm), rough-hairy, prominently veined, mid-green; the leaves are among the largest of any hardy shade perennialGrowing Conditions
Sun Requirements
Requires 1-4 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Part shade to full shade (1-4 hours). Any soil pH 5.5-7.5 — tolerates clay, poor soil, and root competition. Drought-tolerant once established (2-3 years). Spreads by rhizomes — allow ample space. Cut old dead foliage in early spring (March). Deer-resistant. Non-toxic. Zones 5-9.Pruning
Cut old dead foliage to the ground in early spring (March) before new flower stems emerge. No other pruning needed. Thin rhizome spread if colonies exceed desired area.Pruning Schedule
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early spring