Dahlia variabilis, Aztec Sweet Yam, Edible - With impressive brilliant, rich-coloured flowers in deep pink, burnt orange, plum-purple, and blood-red all set against dark crimson foliage. Flowering July to Oct. Height to 3 ft. Flowers & tubers are edible, Semi-Hardy. Originally known as Aztec Sweet Potato or Yam, (but not sweet potato), One of those that have been around for centuries & both decorative & edible (when you are bored looking at it, eat the evidence). Named after the 18th c botanist Anders Dahl & thought to have been tried out as a blight-resistant spud-substitute during the Irish potato famine. Fine Growing in Pots., Seed Count Approx - 20 avg SOWING - Sow in Spring in a greenhouse in pots & plant out once frosts are past, Harvest Autumn, prefers well-drained soil in a warm, sunny position. will tolerate very dry conditions, regular watering will much improve the quality, Annual not frost hardy.. Fine Growing in Pots.