The Amaranthus genus comprises of over 75 different annual and short-lived perennial plants known as "amaranth", and is constantly cross-breeding and hybridizing due to its effective self-seeding nature.
There are a few common amaranth varieties that gardeners and farmers have come to know well; some of which are considered invasive or problematic, but most prized for their beautiful leaves, foliage, and edibility.
All amaranth plants have distinct flower heads full of nutritious grain seeds and leaves that can be eaten in a variety of ways. Understanding the different species and how to live alongside, or cultivate them is important when using them for food and functionality.
Whether you simply find them beautiful, or want to start adding "ancient grains" and greens to your diet, this article will go over everything you need to know about how to grow amaranth.
Overview of Amaranths
All amaranth plants share common aesthetic and growth characteristics. They have broad, pointed, oval leaves that run up a single, woody stalk which can grow up to 8-feet tall in certain varieties.
Once mature, plants sends out fluffy-looking flower heads full of tiny seeds that can be harvested for their grains. These tops either extend the plant's height, or droop over from the weight.
Some amaranth are green, however most of them have a classic red or maroon color, which is why they are prized as ornamental plants. Varieties that grow tall can provide shade for other plants, or act as a small privacy fence in the garden.
As mentioned, amaranth varieties are excellent food crops, and are prominently used in many different types of culinary dishes, throughout history.
Amaranth are believed to be native to South and Central America, parts of Mexico, and the Southern United States, but because of their popularity and fast-spreading nature, you can find amaranth used in many Korean side dishes, Mexican delicacies called "alegria", and Jamaican "callaloo".
Popular Types of Amaranth
While there are many different varieties of amaranth, they resemble each other so closely that many of the cultivars are simply referred to as amaranth without distinction.
It can be helpful to distinguish between a few of the most common types in order to understand their uses better.
"Love Lies Bleeding" (Amaranthus caudatus) is sold as an annual and can be identified by its green leaves and drooping catkin-like red flower heads which fall over as if laying down to die (hence the name!).
Another common, and no-so-beloved amaranth variety is Amaranthus retroflexus commonly known as "pigweed". This one turns up on farms and grass sites and is hard to eradicate if you aren't cultivating it for food.
It's other names are redroot amaranth, tumbleweed, careless weed, and "callaloo". This so-called weed can be used as a trap for pests, to break up compacted soil, or eaten for its leaves which are high in vitamin C and A, folate, and calcium.
Certain varieties are being cultivated specifically as food crops again, as they were often used as ancient grains in tribal communities, and can feed a large portion of people.
Larger plants are grown for their seed heads for a bigger harvest. Smaller plants are better for leaf cultivation, since they taste better than bigger leaves (though you can simply harvest leaves on large plants when they're small).
Amaranthus Cruentus aka 'Velvet Curtains' is one of the most popular ornamental burgundy-colored cultivars with nutritious leaves and seed heads.
'Red-leaf' amaranth is a lovely mix of green and dark red coloring grown specifically for its nutritious leaves that can be cooked like spinach, or eaten raw in salads.
'Callaloo' amaranth is used specifically for the smaller, baby, green leaves, and 'Burgundy' is a classic, tall purplish red plant grown more for its ancient, organic grain seeds.
'Hopi Red' can be grown as microgreens, used to dye clothing, or cultivated for its gluten-free seeds.
Growing Amaranth from Seed
Amaranths are annuals or short-lived perennials in cooler regions, but are such prolific self-seeders that once you have a few established, they'll return year after year, just maybe in a different spot.
Transplanting amaranth isn't always successful, so it's better to sow directly into the ground once any chance of frost is gone. If you want to grow seeds indoors, make sure to give them lots of light once they germinate so that they don't get leggy and can establish healthy roots.
Grow more seedlings than desired, since transplants typically have a low success rate. If sowing directly into the ground, space the seeds to allow for their expected mature growth.
Some plants grow taller than others, so read the info on the seed packet for specific spacing recommendations.
You can also seed vigorously and cull as they start to germinate. Amaranth grow tall and thin and can handle a little crowding as long as there's enough light and airflow.
10-18 inches apart is ideal as the leaves of each plant will end up filling in the space around each other nicely.
When to Plant
Amaranth are recommended for US growing zones 2-11 and will only germinate once soils are warm. Any spring frosts will damage or kill young plants, though mature amaranth are semi-tolerant of frost later in the season.
Check your local frost calendar and watch the weather, but usually you can direct sow seeds in mid-spring once temps are consistently warm. Lightly cover the seeds with soil and keep conditions moist.
Be careful not to flood or disrupt the seeds as amaranth takes a while to get strong enough to handle any sudden moves, hence the poor transplant characteristics.
Drip irrigation would be the best way to water, or rely on spring's consistent light rains. When the seedlings sprout, continue to keep the soil moist and thin them until plants are about 4-inches tall with approximately one foot between them (again, depending on the cultivar's expected size).
Amaranth is very adaptable to most soils, but like most edible plants, will thrive in fertile soil that's been amended with organic material like compost.
Soil must be well-draining—while they can handle consistently moist soil during heavy rain periods, they will not tolerate soggy feet for long.
Loamy soil is ideal, but once amaranth get past their seedling stage, they're very hardy plants and can tolerate average and poor soils. Some varieties like pigweed are even good for breaking up hard, compacted clay soil.
If amaranth are getting the proper light and water, there isn't much need for supplemental feeding. Amaranth turns excess nitrogen, which is a main component in fertilizers, into nitrates.
Nurture seedlings until they are strong, and then don't fuss with the soil too much.
Light and Temperature
All amaranth varieties do best in full sun, especially the fast-growing varieties that get tall.
In extremely hot, dry, desert like conditions or times of drought, amaranth will benefit from part shade, which can happen naturally when planted next to each other.
In general, a minimum of six hours of sunlight a day will be enough to keep amaranth thriving. Ideal warmth and sunlight will allow the plants to reach their full height and produce the most amount of leaves and seed heads for large harvests.
These plants like it warm, just like tomatoes or peppers do. While they can handle a little extra heat and are native to tropical regions, they will need some respite from extreme heat and drought.
Amaranth plants have similar watering needs to plants like tomatoes and peppers, as well, so you can plant among these crops to keep conditions similar.
If no rain is in the forecast, they'll need some supplemental watering during periods of intense heat or drought, and would prefer not to have their soil dry out too much.
Water deeply once a week rather than lightly, more often. They don't like soggy soils, but can tolerate a heavy rain or some over-watering—just don't over-do it.
One-inch of water per week is standard, unless soils are drying out quicker due to wind, sun, and/ or heat. Over-watering can create root rot or fungal diseases, so keep plants spaced out nicely, and only water when there isn't any rain in the forecast for the week.
Harvesting the leaves of your amaranth plant is quite easy. Simply pull them off by hand where it meets the stem, or use small pruners. Smaller leaves are generally sweeter, whereas large leaves are a bit tougher and more bitter.
You can harvest many leaves at once, as long as you don't take more than 50 percent of the plant's foliage. Amaranth are excellent at reproducing leaves once they've been harvested, either by humans or pests!
Yet another reason this is a stable food crop, you can consistently harvest leaves all throughout the growing season.
You'll need to wait until seeds start to dry up to harvest the grains, usually in the early fall, or about three months after planting. Once birds start to peck at them, you know it's time, but you can also get ahead of them by cutting the stalk head and drying them indoors.
To strip the seeds, you need to "winnow" them which is the process of removing the seed from its chaff. This process can be time-consuming, but worth it for the healthy and delicious grain source.
Once seeds are separated, dry them out on a sheet and store them in a mason jar like you would with any other kind of grain.
Amaranth is subject to a number of pests, but not any moreso than other food crops. The main culprits are different kinds of beetles and aphids. Flea beetles will make small holes in leaves, as will caterpillars.
Larger holes could be Japanese beetles or Lygus bugs, and both can cause serious damage if left to their own devices. Aphids can also cause damage by sucking out the plant's juices if allowed to stay on the plant.
Amaranth are often used as a pest-trapping plant as aphids are drawn to certain varieties, mainly the green ones. If you see an infestation, first spray the insects with a hard blast of the hose every day for seven days to rid them organically without pesticides.
If the problem persists, use insecticidal soap to spot treat any areas where stubborn pests continue to flourish.
Plant other pest-repelling plants like nasturtiums, various fragrant herbs like basil, lavender, and rosemary, and members of the allium family like onions and garlic.
Where to Find Amaranth
Many of the green varieties of amaranth like pigweed can be found roadside or growing in your garden around midsummer. Learn how to identify these "free" plants as they are often mistaken for weeds and eradicated quickly.
Red, ornamental varieties are sometimes sold in nurseries or garden centers, but you'll rarely find them in big box hardware store garden centers. Smaller, independent nurseries may cultivate annual varieties, but for specific cultivars for food production, sourcing out organic seed packets is your best bet.
West Coast Seeds and Uprising Seeds are great choices for packets, but check out Etsy for individual growers that may be local to you, and to find specific varieties.
Seed Savers Exchange (seedsavers.org) and seed libraries are also wonderful ways to source out heirloom varieties that people have shared and openly exchange with others.
Local gardening groups can be an excellent source of information on where to find amaranth plants in your area.
Cooking with Amaranth
Amaranth leaves can be added fresh to salads or sandwiches, or cooked into stir-fries and other pan dishes. Like most greens, the leaves will shrivel once cooked, and end up being a lot smaller in size.
Use fresh leaves when possible, or store in the fridge for up to two days in a container. They can be added to pizzas, omelettes, soups, or eaten on the spot!
Leaves contain high amounts of soluble and insoluble dietary fiber, are high in vitamin C, A, and K, as well as B vitamins and other minerals, and in higher amounts than other leafy greens.
The grains are excellent plant-based sources of complete protein, meaning they contain all nine essential amino acids. They boast double the amount of protein found in rice or corn, and slightly more than quinoa.
The seeds are also easier to digest compared to soy or wheat grains, and are gluten-free. They can be cooked like rice or quinoa, ground into meal, or even popped like corn.
Why You Should Plant Amaranth
Amaranth is a plant for the people, and has been all throughout history. It's culinary use was originally the main reason it was planted, as it was able to feed tribes and large communities.
Aztecs grew amaranth for food, and also used it in ceremonies and rituals. Spanish conquistadors knew how important this food staple was, and banned its production after destroying all of the crops.
This was partly to enforce Catholicism, but also to control them more easily since amaranth was such an important nutritional component to their diet. Pigweed and other types of amaranth have been important staples for indigenous people and in poorer parts of the world.
While it's ornamental beauty is a more common reason it's grown in American gardens, food security is affecting even more people who are struggling to afford groceries.
Planting amaranth can greatly increase the nutritional needs of you and your family, or anyone facing food stress.
Pigweed, specifically has shown great resistance to Roundup and other toxic herbicides, meaning it can withstand the harmful monoculture tactics of modern agriculture.
It also has the ability to absorb carbon dioxide from the atmosphere and is considered a "C4" plant. C4 plants are highly adaptable to extreme temperatures and drought, making it an excellent crop to battle against climate change.
Whatever variety you choose to go with, amaranth plants offer many benefits. Once you learn how to grow amaranth, it will easily come back every year if you leave the some of the seeds to drop into the soil.
It's one of the easiest plants to cultivate, is highly nutritious, and beautiful: something every gardener loves to hear!