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‘Purple Knight’ 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 subtropical areas of Central and South America. Their flowers are generally an afterthought. This plant works well for edging, as an annual ground cover, 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.

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  • 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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