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Calico plant

Alternanthera dentata 'Purple Knight'

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This dark-leaved, tropical foliage plant loves heat, and is useful spreading through a bed, border, or in a container where its deep purple leaves can contrast with brightly colored flowers or foliage. Alternanthera are native to tropical and sub-tropical areas of Central and South America. Their flowers are generally an afterthought. This plant works well for edging, as an annual groundcover, or in a formal knot garden.

Noteworthy CharacteristicsPurple-ruby foliage that is almost black. Performs well in high heat, where its color deepens and becomes richer. Easy to grow from seed.

CarePlant out after the frost-free date in moist but well-drained soil in full sun (for best color) or partial shade. Pinch or clip back to maintain compact form.

PropagationSow seed at 55°  to 64°F as soon as ripe, or in spring (seedlings may vary in color). Divide in spring. Take cuttings in late summer.

ProblemsGenerally trouble-free, but spider mites and Fusarium wilt may be problems.

  • Genus : Alternanthera
  • Plant Height : 1 to 3 feet
  • Plant Width : 1 to 3 feet
  • Plant Type : Annuals
  • Uses : Containers, Ground Covers
  • Light : Full Sun to Partial Shade
  • Moisture : Medium Moisture
  • Growth Rate : Moderate
  • Maintenance : Moderate
  • Foliage Color : Purple/Burgundy
  • Characteristics : Showy Foliage
  • Plant Seasonal Interest : Summer Interest

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