Amaranth is a plant. The seed, oil, and leaf are used as food. The entire plant is used to make medicine. Amaranth is used for ulcers, diarrhea, swelling of the mouth or throat, and high cholesterol, but there is no good scientific evidence to support these uses.Amaranthus tricolor. Also known as Chinese spinach. This heat lover is a very nutritious leaf vegetable. This variety has large, fleshy, pale-green or burgundy and green leaves that can be enjoyed raw in salads. They can also be cooked quickly, faster than spinach. Plant Red Leaf amaranth seeds in early summer in warm soil with good drainage. Enjoy as micro-greens, baby leaf salad greens, or full size cooked greens. The flavour pairs well with garlic and oyster sauce. The plants reach about waist high before flowering in late summer. Be sure to harvest before the flowering stage for the best flavour.