Gerard's Thorowax (Bupleurum gerardi)

Gerard's Thorowax

Bupleurum gerardi

Its delicate umbels carry soft yellow blooms, a quiet wildflower charm. Biennial or short-lived perennial herb; common name: Gerard's Thorowax.

Full sun
1–2/week
Beginner
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Plant Needs

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Sunlight Full sun to partial shade; tolerates dry, exposed hillside or meadow sites
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Watering Water deeply when the top 2 cm of soil is dry; drought-tolerant once established with a mature taproot
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Temperature Hardy to -15°C; withstands hot, dry summer conditions without supplemental watering
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Characteristics

  • Leaf: Linear to lanceolate, glabrous gray-green foliage, clasping the stem at the base
  • Flower: Tiny yellow star-shaped blooms arranged in flat-topped umbels
  • Stem: Erect, smooth-textured stem with branched upper growth
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Care Guide

Watering

Keep soil slightly moist during active growth periods

Fertilization

Optional diluted low-nitrogen feed once monthly. Fertilization is not required for established wild plantings

Eggshell powder topdressing:Crush dried eggshells into fine powder; sprinkle lightly on soil surface to add calcium without risk of root burn
Pruning
  • Deadhead spent blooms to encourage prolonged flowering and self-seeding
  • Cut back entire plant to ground level after flowering to tidy growth
  • Remove yellowing foliage to improve air circulation and reduce pest risk
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Toxicity

Warning: this plant may be toxic.

Pets & Humans

Pets: ASPCA does not list this species as toxic to cats

Humans: No documented toxic effects for humans; used in traditional folk medicine in limited contexts

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Garden Uses & Culture

Culture: N/A

Usage: Traditional European folk medicinal herb for digestive support; ornamental wildflower for meadow plantings