Amaranth is a native flower that brings color and drama to the garden, as well as an ancient grain which is highlight nutritious! A warm-season plant, amaranth is planted after final spring frosts. Learn how to plant, grow, and care for amaranth.
Amaranth plants are members of the genus Amaranthus, of which there are about 75 species. Amaranths are often grown for ornamental purposes and some varieties make stunning additions to cut flower arrangements or fall wreaths. Amaranth is also grown for its salad green–like tasty leaves and, more importantly, for its seeds, harvested as a nutritious grain.
In the garden or landscape, varieties usually grow 2- to 4-foot high. This flowering plant is often a bright magenta color but also comes in golden-bronze tones, adding eye-catching color and texture in beds, borders, and cottage gardens. It also makes an excellent cutting flower. Plus, the songbirds love its seeds in the autumn.
As a grain, this New World native has a long history in Indigenous agriculture of South America and has been cultivated as a food for thousands of years by civilizations around the globe. Both the tiny seeds and the young leaves are edible and highly nutritious. Whole amaranth grains can yield 12 to 14% protein. They are gluten-free and make an excellent source of whole grains for people avoiding gluten.
Note: Several amaranth varieties are considered noxious weeds by farmers, particularly A. palmeri also known Palmer amaranth. A. palmeri has developed resistance to herbicides and has become a significant agricultural weed. Amaranthus retroflexus (redroot pigweed) is another common weed species.
The young leaves can be treated as cooking greens. Nutty and flavorful, the seeds are ground into flour, used as whole grains in snacks, or cooked like quinoa. They can be stewed into porridge and even popped like popcorn! Check this page from Iowa State University for more reading on how amaranth grain is used.
The most common seedhead and leaf species grown by gardeners and homesteaders are A. hypochondriacus, A. caudatus, and A. cruentus.
Amaranth is a warm-season plant which likes full sun, at least 6 hours per day. It will survive in partial sun but may not grow as large or yield as highly. Loose, fertile, and well-drained soil is ideal, but amaranth will grow in less-than-perfect conditions. It is not picky about pH, and will tolerate dry conditions once established. Amaranth will try to grow for you no matter what conditions you give it.
When to Plant Amaranth
Amaranth can be direct-seeded or transplanted from starts. It is not frost tolerant, so wait until the last frost has passed, and the soil has warmed a bit. If starting seeds indoors, begin sowing about 6 to 8 weeks before the last frost.
Don’t forget to harden seedlings off (slowly adapting them to the outdoors) before transplanting them into the garden.
How to Plant Amaranth
To direct-seed amaranth:
Prepare the bed and sow sparingly—the plants get quite large.
Barely cover the seeds with a light brushing of soil.
Running your hands lightly over the seeds is likely enough to cover many of them.
Thin to about one every 12 inches once a couple sets of true leaves are out.
To start amaranth indoors:
Sow them in soil blocks or prepared trays of well-moistened seed starting mix.
Plant the seeds about 1/8 inch deep.
If planting in cell trays, drop two seeds per cell and thin to one per cell if necessary once they have germinated. Snip the extras, don’t pull them out.
Keep them lightly moist but not soggy, and provide plenty of light once they sprout.
Harden off and plant outside once the last frost has passed, about when you transplant tomatoes or peppers.
Amaranth grows slowly for the first month and can easily be outcompeted by weeds (including the wild, noxious amaranths). After the plants have 2 to 3 sets of true leaves and are 8 to 10 inches tall, they grow rapidly and will close the canopy, shading out the other weeds.
They are not heavy feeders like corn but will appreciate some compost worked into the soil before planting. Mulching can help with soil moisture and weed pressure when the plants are younger.
Once established, they are somewhat drought tolerant but will benefit from watering in the dry, hot parts of summer.
‘Coral Fountain’ (A. caudatus) is a flowing, cascading ornamental variety with lovely coral-colored blooms.
‘Hot Biscuits’ (A. cruentus) is the current rage of the flower farming world. Loads of large blooms are perfect for autumn arrangements; it is a prolific performer.
‘Love-lies-bleeding’ (A. caudatus) is another gorgeous flowing and cascading variety with blooms the color of a fruity red wine.
Grain and Leaf
‘Golden Giant’ (A. hypochondriacus) is a large, heavy seed producer, with some growers reporting yields of up to one pound per plant. Beautiful golden grain and tasty young leaves. If you are looking for grain, this variety is hard to beat.
‘Chinese multicolor’ (A. tricolor) is tasty in salads and stir fry, with unique leaf patterns.
‘Aurelia’s Verde’ (A. cruentus) is a green head amaranth rich in vitamins and iron, reportedly saved from the Mayan communities of Central America.
Harvesting amaranth for cut flower arrangements is as simple as snipping off the head and placing the stem in a bucket of cool water until you are ready to use it. Amaranth blooms typically will last 7-10 days in the vase.
To harvest as grain:
Check for the grain to be ready. On mature flowers, hold your hand under a flower and lightly brush it or rub. It’s likely ready if a bit of grain falls off in your hand. If only a seed or two drops, wait another few days and check again.
If you notice flocks of birds landing in your amaranth, it’s time to harvest, quick!
Harvest the entire flower head, trimming it off with shears or secateurs.
Over a large bowl or tablecloth, lightly rub and agitate the flowers, letting the grain fall free to be captured. Shaking the heads in a clean pillowcase or bag can also work well.
Winnow the grain by pouring from one bowl to another in a light breeze or in front of a fan. Amaranth is hull-less, but bits of dried flowers, insects, and chaff can be removed.
The insects who stowed away will often hop along if you set the bowl near the ground and the sides are not too steep. Leave it for a few hours, and most will look for new homes.
Store the grain in an air-tight container.
Wit and Wisdom
Amaranth has been cultivated for several thousand years in civilizations around the globe.
The amaranth plant was highly significant in Aztec culture. The Spanish explorer Hernán Cortés banned its cultivation and threatened anyone caught growing it would be put to death.
Amaranth seeds contain about 14 to 16% protein, are well balanced in amino acids, and high in the amino acid lysine.
Grain-type amaranth seeds can be popped and eaten like popcorn.