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Blue throatwort

Trachelium caeruleum

This species bears dome-shaped flower heads several inches across that are crowded with tiny, tubular amethyst or white flowers that look somewhat like the blooms of an allium. It has lance-shaped, toothed leaves in hues of cordovan purple or deep green brushed with plum highlights. It blooms over a long season. Though it is a perennial, blue throatwort performs wonderfully as an annual and blooms summer to fall. Plants grow to about 3 feet tall and wide.

Noteworthy CharacteristicsExcellent cut flowers.

CareProvide neutral to slightly acidic, well-drained soil in full sun with some shade in the heat of the day.

PropagationSow seed in a cold frame when ripe or at 55° to 60°F in spring, or where they are to bloom in late spring. Rooted cuttings may be overwintered in a protected place.

ProblemsAphids, spider mites.

  • Genus : Trachelium
  • Plant Height : 1 to 3 feet
  • Plant Width : 1 to 3 feet
  • Zones : 10, 11, 9
  • Uses : Containers
  • Bloom Time : Early Fall, Late Summer, Summer
  • Light : Full Sun
  • Maintenance : Low
  • Moisture : Medium Moisture
  • Growth Rate : Moderate
  • Plant Type : Perennials
  • Characteristics : Showy Foliage
  • Plant Seasonal Interest : Summer Interest
  • Flower Color : White

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