#periwinkle  chiefly trailing poisonous plants with blue flowers
  supertype:  subshrub__suffrutex  low-growing woody shrub or perennial with woody base
  member of:  genus_Vinca
  subtype:  Vinca_minor__myrtle  widely cultivated as a groundcover for its dark green shiny leaves and usually blue-violet flowers
  subtype:  large_periwinkle__largeperiwinkle__Vinca_major  plant having variegated foliage and used for window boxes

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