Amaranthus blitum, commonly called purple amaranth or Guernsey pigweed, is an annual plant species in economically important plant family Amaranthaceae.

Native to the Mediterranean region, it is naturalized in other parts of the world, including much of eastern North America. Although weedy, it is eaten in many parts of the world. The Greeks call the Amaranthus blitum var. silvestre, vlita (Modern Greek: βλίτα), and eat the leaves and the tender shoots cooked in steam or boiled and then served with olive oil, lemon and salt.