Can you eat pigweed

According to the CalFlora website (http://www.calflora.org/), 21 species of amaranths occur (to some extent) in California. While many are non-native, a few, including prostrate pigweed (Amaranthus blitoides) and Palmer amaranth (Amaranthus palmeri), are indigenous. While it may be convenient to lump all of the genus Amaranthus together when considering weed management options, proper identification is important for understanding the potential for crop yield loss (not all amaranths were created equal with respect to competitiveness) and the possibility of herbicide resistance (populations of Palmer amaranth with resistance to glyphosate have been confirmed in the state), etc… This post will, hopefully, help you to distinguish between five weedy amaranths: redroot pigweed (Amaranthus retroflexus), prostrate pigweed (Amaranthus blitoides), tumble pigweed (Amaranthus albus), waterhemp (Amaranthus rudis), and Palmer amaranth (Amaranthus palmeri).

Let’s get started…

So, you are looking at a plant that has 1) alternating leaves that are notched at the tips, 2) nondescript green flowers, 3) and that is producing prodigious amounts of small, shiny, black seeds. You are pretty sure that you are looking at a pigweed but you aren’t sure which one. How can you tell them apart? What combinations of traits separate one species from another? Below are some identifying characteristics to help you when making your decision.

Redroot pigweed (Amaranthus retroflexus)

Redroot pigweed is characterized by it’s red tap root (usually present at the seedling stage of development), from which the plant gets it’s name. Plants are erect and usually around 3-4′ in height, although they can grow larger. Leaves are round to oval in shape and have prominent veins; both leaves and stems are covered in fine hairs (pubescent). Young leaves may appear purplish on the underside. Male (staminate) and female (pistillate) flowers are produced on the same plant (defined as being monoecious) in terminal flower spikes that are comprised of short, thick branches. Please see the UC IPM website for more information about redroot pigweed: http://ipm.ucanr.edu/PMG/WEEDS/redroot_pigweed.html .

Red coloration on the root of a young redroot pigweed plant. If you look closely, you can also see some fine hairs on the stem of the plant, which give it it’s rough appearance.

Leaves of redroot pigweed are round to oval in shape; young leaves may be purple on the underside.

Male and female flowers are produced on the same plant in terminal flower spikes comprised of short/squat and thick branches.

Prostrate pigweed (Amaranthus blitoides)

Like it’s name suggests, prostrate pigweed has a very flattened (as opposed to erect) growth habit. Just because it is flat doesn’t mean that the plant is small, though; branches can be up to 2′ in length. Leaves are somewhat spoon-shaped (narrower at the base), small (<1.5″ long), and are often dark green and waxy-looking. Stems are mostly smooth, fleshy (succulent), and often red in color. Male and female flowers are produced on the same plant, but not in terminal spikes; instead, the flowers of prostrate pigweed are produced in clusters in the leaf axils. The Illinois wildflower website has more information about this species at: http://www.illinoiswildflowers.info/weeds/plants/pros_pigweed.htm.

Prostrate pigweed leaves are small, narrow at the base, and waxy in appearance.

Prostrate pigweed leaves are small, narrow at the base, and waxy in appearance.

Prostrate pigweed flowers are produced in clusters in leaf axils.

Prostrate pigweed has a flattened growth habit and reddish to red stems.

Tumble pigweed (Amaranthus albus)

Tumble pigweed is shrubby in habit; the plant grows to heights of about 3′ and can be highly branched. Leaves can be small (<1.5″ long), are egg-shaped, and may have wavy edges. Stems and leaves are light green in color. Like prostrate pigweed, the species is monoecious with flowers produced in spiny clusters in leaf axils (not in terminal flower spikes). Additional information describing the differences between tumble and prostrate pigweeds can be accessed here: http://drkaae.com/Weeds2011/Pigweed.htm.

Tumble pigweed leaves are light green in color, oval to egg-shaped, and have wavy edges.

Tumble pigweed flowers are produced in spiny clusters in leaf axils. Note the lack of sharp bracts with prostrate pigweed.

Waterhemp (Amaranthus rudis)

Waterhemp is an upright/erect pigweed species (growing to heights of 5-7′). The stems are smooth (hairless) and range from green to red in color. Although leaf shape can be variable, most leaves (especially older ones) are long and slender/narrow; leaves are typically dark green and shiny. Unlike redroot, prostrate, and tumble pigweeds, waterhemp produces male and female flowers on separate plants (defined as being dioecious). Flowers are primarily produced on long (up to 1′ or more in length) and minimally branched, terminal flower spikes or on spikes that arise from upper leaf axils. For more information about waterhemp, please see the following website: http://www.illinoiswildflowers.info/weeds/plants/water_hemp.htm.

Waterhemp leaves are dark green, shiny, hairless, and slender.

Waterhemp stems are smooth/hairless and can vary with respect to color.

Male (left) and female (right) waterhemp flowers are produced in terminal flower spikes that are help on separate plants.

Palmer amaranth (Amaranthus palmeri)

Palmer amaranth is also an erect pigweed species (growing to heights >6-8′). Like waterhemp, the stems are hairless and range from green to red in color. Leaf shape can be variable, but most leaves are egg-, diamond-, or lance-shaped; leaves may sometimes exhibit a white or purple, chevron-shaped watermark on them. Leaf petioles (especially on older leaves) are as long or longer than the leaf blades. Palmer amaranth also produces male and female flowers on separate plants (dioecious). Flowers are primarily produced on long (up to 2-3′ or more in length) and minimally branched, terminal flower spikes or on spikes that arise from upper leaf axils. Female Palmer amaranth flowers can be distinguished from waterhemp by the presence of sharp bracts.For more information about Palmer amaranth and how to distinguish it from Waterhemp, please see the following website: https://www.extension.purdue.edu/extmedia/WS/WS-51-W.pdf.

Palmer amaranth leaves. Some people note that the leaf arrangement resembles that of a pointsettia.

Leaf blades of waterhemp (left) and Palmer amaranth (right).

Petiole differences between waterhemp (left) and Palmer amaranth (right).

Male (left) and female (right) Palmer amaranth flowers are produced in terminal flower spikes that are help on separate plants. Note the presence of sharp bracts associated with the female flowers.

This blog post isn’t meant to be the end all and be all of pigweed ID (many other species that occur in California aren’t even included…), but it is meant to help you get started. Your local Cooperative Extension office personnel or Master Gardeners can also assist you.

Clockwise from upper left: Tumble pigweed, prostrate pigweed, waterhemp, and Palmer amaranth.

All pictures by Lynn M. Sosnoskie.

Amaranth & Pigweed

  • Is all pigweed edible?
  • Ancient grain?
  • Nutrition
  • Identification
  • Habitat
  • Harvest & process
  • How to cook

Mention “pigweed” in a south Georgia feed and seed and you’re liable to hear a slew of words unfit for Sunday service. Pigweed has few friends in south Georgia or any of the farming communities that have been stricken by its glyphosate-resistant tenacity.

But mention “amaranth” in an Asheville co-op and you’ll likely get an earful of evangalism for one of the oldest intentionally cultivated food crops that we know of.

And yet, they’re the same plant.

“Pigweed” is a common name for a few different plants, including lambsquarters, but this particular pigweed is the one whose genus is Amaranthus.

The plant that plagues cotton and soybean fields in the South is mostly Palmer amaranth (Amaranthus Palmeri), aka Palmer pigweed, a champion of natural evolution — one that has emerged triumphant over the GMO assault and retaliated with a vengeance akin to karmic retribution.

There are around 60 species of amaranth — all have varying degrees of good-to-eatness.

Is All Pigweed Edible?

In spite of some wild rumors, all amaranth can be eaten — even glyphosate-resistant Palmer pigweed — with a couple of caveats. For one, any plant that survives the onslaught of toxic petro-pesticides will most likely harbor the toxic constituents of the pesticide and pass them on to whomever eats the plant.

Amaranth also has a propensity to accumulate nitrates and oxalates, which can make it unpalatable and unsafe for eating, especially when it grows in soil that’s been over-exposed to nitrates from commercial fertilizer.

The seed can only be eaten when it’s cooked, as it inhibits nutrient absorption when consumed raw.

How does it taste? As greens go, most folks consider amaranth better than acceptable but probably not what you would call “top shelf”. I’m partial to its cousin, lambsquarters, but amaranth leaves are definitely worth foraging.

I have a friend who prefers amaranth over lambsquarters for flavor, though. Maybe it’s more of an acquired taste. Picked young enough, amaranth leaves do make a good, mildly flavored steamed green, reminiscent of steamed spinach, and the flavor varies from species to species, some more bitter than others.

Cooked amaranth seeds are sort of nutty. The flavor is sometimes described as earthy or grassy.

Ancient Grain?

Not really. Ancient super-food? Maybe. But, in technical terms, amaranth seeds aren’t really grain. Like buckwheat, amaranth is considered a “pseudo-cereal,” which basically means it’s not in the grass family like wheat and corn — it seems like a subtle difference to me but apparently pseudo-cereal seeds are not the same as “true” grains.

Ancient it is, though. It was a main staple of the Aztecs and was cultivated by them as long as 8,000 years ago. Before that, it was foraged wild.

One of the amaranth seed’s most attractive traits, in an era of anti-wheat, is simply the fact that amaranth is gluten-free. And unlike a lot of gluten-free wheat alternatives, it’s really good for you.

Nutrition

In terms of nutrition, “amaranth” is usually synonymous with “amaranth seed,” so most of the published nutrition information refers to the seed, or amaranth flour. For the casual forager, though, amaranth leaves are more accessible and require little processing effort compared with the seed.

The greens are similar to spinach, beet greens, and chard — they’re all in the same family, Amaranthaceae — but amaranth has more than twice as much vitamin C as kale and four times more than spinach. It’s also high in vitamin A and calcium, as well as a host of other healthful vitamins and minerals. See the USDA’s amaranth leaves nutrition table for details.

Amaranth seed has more protein and fewer carbohydrates than both buckwheat and white rice, and its protein is supposedly more complete. According to this study, amaranth seed’s protein is similar to animal protein. See the USDA’s amaranth seed nutrition table for a full list of nutrients.

Identification

Amaranth stem

Pigweed plants can grow to over six feet high with alternating oval to diamond-shaped leaves that may be up to six inches long.

The greenish stems tend to turn red as they mature, and although most species of pigweed grow upright, prostrate pigweed (Amaranthus blitoides and Amaranthus blitoides) grows along the ground.

The stems are usually smooth or slightly hairy except for spiny pigweed (Amaranthus spinosus), which has thorns — I first discovered this when unsuspectingly weeding my garden with bare hands. Of course the wickedly thorny variety is what usually volunteers in my beds.

The tiny flowers of amaranth grow by the hundreds along the stem and are easily recognized in fields where they emerge above crops like cotton. The flower spikes are probably the plant’s most identifiable trait.

The flowers eventually dry out and yield tiny husked seeds which may then be harvested.

Where Can Pigweed or Amaranth Be Found?

North America is home to both native and introduced species of pigweed — at least one species can be found throughout the entire continent.

Amaranth’s/pigweed’s favorite stomping grounds are disturbed areas like fields, yards, and the edges of woods. It seems to tolerate most soil types but it really thrives in the rich soil of a well-amended garden. I frequently see it on the edges of fields and parks. If you find lambsquarters, you’re likely to find amaranth growing nearby, as they’re similar plants and do well in similar conditions.

Since amaranth is such a weedy, farmer-plaguing plant, be careful harvesting in areas that may have been sprayed with toxic chemicals — or that may have absorbed high levels of nitrates from fertilizer.

Harvest & Process

For greens, pick amaranth leaves from young plants avoiding larger leaves — smaller to medium-sized leaves are more tender and more nutrient-rich than their bigger counterparts.

The seeds are ready to harvest when they start falling off of the plant, usually towards middle to late summer. First cut off the entire flower head and put in a paper or fine mesh bag, and then let them dry for a week or two in a well-ventilated, shady area, like open-air barn. Or you can use a room or closet with a dehumidifier running.

Amaranth flower head

When the seeds are dry and ready to separate, either thresh by rubbing the flower heads in your hands over a container, or by gently beating the bags of flower heads with a stick. This works better if you have mesh bags.

Then sift the seeds through a strainer to remove the coarser chaff. Store in clean jars or use right away.

How to Cook

Cook young tender pigweed leaves as you would spinach; steam or sauté/stir-fry in butter or oil.

Pigweed seeds should never be eaten raw. To cook, add to boiling water and simmer uncovered for 25 to 30 minutes. For more of a soupy porridge-type texture, use one part seeds to three parts water. One to one makes a really firm consistency. One part seeds to two parts water is a happy medium.

In the field. For your farm.

Weed identification at the seedling and immature stages can be difficult but is often necessary because scouting should occur before weeds reach 4 inches in height. At emergence before a full set of true leaves appear, pigweeds can be confused with other weed species such as wild buckwheat, eastern black nightshade, and ladysthumb. In addition, the pigweeds: Palmer amaranth, waterhemp, redroot pigweed, Powell amaranth, and smooth pigweed, are not easily separated by species at the immature stages. The first step is to look at the leaves and stems because Palmer amaranth and waterhemp do not have any hairs compared to Powell, redroot, and smooth pigweed, which do have hairs but they may not be obvious at the immature stage. If the plant looks like it may be Palmer amaranth or waterhemp, then the next step is to look at the leaf shape and petiole. Palmer amaranth has a more rounded leaf shape and a petiole that is longer than the leaf itself.

For a list of resources available by species, guides for the most common weed seedlings, and links to the WeedID smartphone apps, take a look at the Weed Info page. There are several Extension resources available to help with pigweed identification including:

  • “Palmer amaranth seedling identification,” Purdue University, 7.5 minute video

The videos provide a nice introduction to identification, particularly, if using the printed guides. Pigweeds present a tough set of management challenges, for instance, very high growth rates, extended emergence over most of the growing season, and high seed production. The United Soybean Board’s TakeAction website has publications on the management of Palmer amaranth and waterhemp. Populations of Palmer amaranth and waterhemp have been confirmed resistant to glyphosate in Wisconsin. To read more about glyphosate-resistant pigweeds in Wisconsin, please consult these fact sheets: Palmer amaranth resistance and waterhemp resistance.

This article was posted in WCWS and tagged identification, Palmer amaranth, pigweed, video, waterhemp.

What Is Pigweed – Learn About Pigweed Plant Uses

Using pigweed plants in the kitchen is one way to manage this plant that many gardeners call a pest or a weed. Common throughout the U.S., pigweed is edible from its leaves and stems down to its small seeds.

What is Pigweed?

Pigweed (Amaranthus retroflexus) is one of the most common weeds seen in pastures in the U.S., but you are also likely to see it in your garden. Like other weeds it is tough, growing in a variety of conditions and resisting many herbicides.

There are actually many types of plant called pigweed, a vast family also known as amaranth. The family probably originated in the Americas but now grows throughout the world. It includes cultivated cereals as well as several plants considered to be weeds.

The pigweeds you are likely to encounter in U.S. gardens all look similar and may grow in height between just 4 inches (10

cm.) to over 6 feet (2 meters). The leaves are simple and oval-shaped, often with some red coloration. The stems are sturdy and the flowers are unremarkable.

Is Pigweed Edible?

Yes, the weeds in the garden we call pigweed, including prostrate pigweed, from the amaranth family, are edible. Every part of the plant can be eaten, but the young leaves and growing tips on older plants are the tastiest and most tender. The seeds are nutritious and edible and are not difficult to harvest.

So, how can you eat pigweed? Use it in most of the ways you would any other edible green. For raw eating, stick with the young leaves and new shoots. These can be used like salad greens or spinach. The young and older leaves can also be sautéed or steamed, used as you would chard or turnip greens. The leaves contain vitamins A and C, and iron and calcium.

Pigweed plant uses include harvesting and eating the seeds, raw or cooked. The seeds are particularly nutritious and are high in protein, fiber, and vitamins A and C. You can eat the seeds raw, roasted, cooked as a hot cereal, and even popped like popcorn.

If enjoying pigweed from your garden, be sure that you have not sprayed pesticides or herbicides on it before harvesting. Also, be aware that some varieties, like Amaranthus spinosus, have sharp spines that will need to be avoided or removed.

Disclaimer: The contents of this article is for educational and gardening purposes only. Before using or ingesting ANY herb or plant for medicinal purposes or otherwise, please consult a physician, medical herbalist or other suitable professional for advice.

A Tale of Two Pigweeds

Hail pigweed, well met!

The uninvited lone redroot pigweed plant that appeared two summers ago on my terrace was so effective at spreading its dust of seeds that they are now in every pot. That is what makes a weed: irrepressibility. What clinches the definition is that it is an unwanted plant.

But I do want it. I find the leaves and young stems of Amaranthus retroflexus more appealing than spinach or chard. It is also a rare warm-weather green, filling a leafy gap in the seasonal eater’s year.

Many a spurned plant has been called pigweed, and perhaps some lucky pigs have benefited from them, in health and in pleasure. Redroot pigweed, splayed in our edible spotlight, is an annual herb whose celebrity cousins are the statuesque red-tressed supermodels collectively called red amaranth. Domesticated centuries ago, red amaranth’s seed was a labor-intensive staple of the Aztec diet, and these pedigreed vegetables are still cultivated for food and for visual drama. Jamaica’s sonorous callaloo relies upon yet another species of amaranth (there are more than 60, not counting hybrids) for its soulful and leafy base.

Poor redroot pigweed languishes insignificantly in the retinue of these honored members of amaranth society. It is not a pretty plant. For one thing, it sprawls, heading sideways before it thinks to look up. It has no showy flower or seed heads. It is plain green. It hangs out on sidewalks. And it insinuates itself where it was not invited. Once established it head-butts the plants we like to nurture. It has grown resistant to herbicides. Where it appears in rows of cultivated crops it is met with a deluge of increasingly ineffective and virulent poisons. It is often considered toxic to livestock because it absorbs so much of the nitrogen in commercially applied chemical fertilizers—converting it to nitrates—that it becomes a reflection of our agricultural malpractices and turns on us, giving as good as it gets.

On Manhattan island, agribusiness has not taken hold, however, and the pigweed reaching tropical proportions by summer’s sticky climax is usually safe to eat. In community gardens it is yanked out; on terraces and rooftops, gardeners toss it onto a wilting heap; and in tree pits, parks and open lots it flourishes, plain green and anonymous.

Foragers, choose your pigweed patch with care, and common sense. Avoid the tree pits, beleaguered receptacles for the noisome urban effluvia. But visit a community garden and perform some free and welcome weeding. Collect it from a clean park. At summer’s end, harvest seeds from a mature plant, sow them in a sunny spot and look forward to your own welcome weeds next year.

In Cape Town, Tipsy Titoti, my parents’ housekeeper and a second mother to me, taught me to make a traditional rural stew based on edible green weeds, known as morogo in the Sesotho language. I cook pigweed in water until tender, with scallion greens and a little potato or mealie meal (cornmeal or grits, Stateside). With nothing more than salt as seasoning, this becomes a deeply comforting and nutritious broth. Crostini topped with sautéed pigweed and garlic is a bracing tonic: the plant is high in protein, iron, calcium and essential amino acids.

There is another pigweed, and it grows everywhere: Chenopodium album—also known as lamb’s-quarters and white goosefoot. Like redroot pigweed (and spinach and beets and quinoa), it belongs to the family Amaranthaceae, and is lovely to eat. Happily for those shy of supping from the sidewalk, it has begun to appear at farmers markets. Its powdery gray-blue leaves are delicious when raw in spring salads but equally rewarding as a pot herb later in the year. Pick the tops from the summer-tall plants and prepare them as you would any more familiar green. Wilted and sautéed, they are an excellent side to steak, still sizzling from the grill. For a simple supper I cook the chopped leaves in a lemony broth to which I add a poached egg at the last minute. I make a pigweed tart, topping flaky olive oil pastry with the cooked greens, oil-cured olives and cream whisked with egg yolks. The cooked, cooled leaves are a hearty lunch, tucked into pita bread with a dollop of garlicky yogurt and a whisper of sumac.

Our claustrophobic city summers offer a few compensations. These pigweeds number among them. For anyone who wants to eat well, they are an old, new ingredient whose potential has barely been explored in our cosmopolitan kitchens. And for a forager, they satisfy the thrill of the hunt and provide a reason to head out into the muggy cloud.

For more urban forager columns and recipes, go to EdibleManhattan.com.

Photo credit: Marie Viljoen

Garden News Blog

Weed of the Month: Pigweed

By Saara Nafici | August 12, 2017

Pigweed may be aggressively pulled from gardens and tree beds in the United States, but it’s lovingly cultivated in other parts of the world. Amaranthus retroflexus is known by many other names besides pigweed, including green amaranth, redroot amaranth, careless weed, tumbleweed, and callaloo. Like other members of the amaranth family, it has a storied history and an important role as a food staple in many cultures.

The plant itself is rather unremarkable looking, with dark green, pointed leaves oppositely arranged along a tall stem and inconspicuous green flower clusters. Its designation as a weed lies in the fact that each plant can produce upwards of 100,000 seeds, ensuring many generations per season.

The seeds themselves are rich in protein and have a higher protein content than rice, sorghum, or rye. They can be easier to digest than soy, wheat, or dairy and can be ground into a meal or popped like corn! Another species, Amaranthus cruentus, is used to make a sweet snack sold on the streets of Mexico called alegria, or happiness. I make this with students every fall, and while the popping is tricky, the results are delicious.

The Aztecs grew Amaranthus cruentus for both the seeds and the dark-red flowers, which were used ritualistically in ceremonies. The Spanish conquistadors destroyed the fields and banned amaranth production, ostensibly as part their campaign to convert the population to Catholicism. Or perhaps they recognized how important it was as a food source for a formidable opponent.

The leaves of pigweed are also incredibly nutritious. They’re high in vitamins A and C and folate, as well as calcium. In Jamaica, pigweed is known as callaloo and is a culinary staple. Here in NYC, you can find it for sale in West Indian markets. In can be stewed, sautéed, tossed into a stir-fry, added to an omelet—there is no wrong way to cook pigweed! Recipe references can be traced to India, Nepal, Indonesia, Guatemala, the Philippines, China, Nigeria, Uganda, Kenya, Greece, Lebanon, and Brazil. Pigweed has been flourishing and feeding humans internationally for centuries.

Finally, while various amaranth species are often considered among the “ancient grains” that are making a comeback, Amaranthus retroflexus also has real potential as a food crop of the future. First, it has developed a resistance to the common weed-killing pesticide glyphosate (Roundup), which means that it can compete and thrive in our increasingly toxic agricultural fields. Second, pigweed performs a particular type of photosynthesis called C4 carbon fixation. C4 plants are able to more efficiently absorb atmospheric carbon dioxide than C3 plants and are adapted to higher temperatures and drier conditions. May we all be as prepared to handle climate change as pigweed!

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Redroot pigweed

Amaranthus retroflexus L. Family: Amaranthaceae Life Cycle: Annual Plant status: Weed Habit: Redroot pigweed is named for its red, thick taproot it develops. Often lower stems are also reddish in color. Redroot pigweed has a tall, usually erect habit, commonly found growing 2 to 4 feet tall. With little other vegetative competition, it can reach heights much greater. It develops lateral shoots that allow it to form tall clumps. If mowed repeatedly, this weed can grow and appear prostrate in habit. Mature plants have coarse hairy stems. Leaves vary in size up to about 7 inches and have noticeably long petioles. They are alternate along the stem having very prominent veins. Leaves lower on the plant are oval to diamond shaped, while upper leaves are lance shaped. Flowers: Inconspicuous green flowers cluster form dense terminal and auxiliary panicle like spikes. Flowering usually occurs in early summer through the first frost. This weed can flower when only several inches tall. Favorable environments: Container Field Greenhouse Favorable environment notes: Redroot pigweed thrives in areas of disturbed soil common to agricultural crop lands such as field nurseries, orchards, row crops and vineyards. Sunny utility areas such as roadsides, pasture lands and landscaped areas are commonly inhabited by this weed as well. Redroot pigweed also can be a problem in outdoor container and gravel areas of nursery operations. It is often seen growing along the outside perimeter of greenhouses and occasionally inside the greenhouse near side vents. Dissemination: Redroot pigweed reproduces only by seed. Seeds are very tiny (1/25th of an inch, 1 mm) shiny and dark colored. Management link: Of interest: This plant is nearly impossible to differentiate from related species Powell amaranth, A.powellii . It can be distinguished by close examination of the flower bracts. Powell amaranth has longer, narrower and more pointed bracts than redroot pigweed.

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