Some tasty greens are beginning to emerge. I saw some young lambsquarter recently and now redroot pigweed (Amaranthus retroflexus) is showing itself. If you like mild cooked greens reminiscent of beet greens, spinach or Swiss chard this one’s for you. It’s also difficult to confuse with anything else except maybe its prickly cousin the spiny amaranth. You won’t make that mistake twice.
Pigweed has diamond shaped leaves, usually with a little notch in their tips. When less than a foot tall entire plants are smooth and tender. Leaves begin to get rough and hairy as they mature, so if you are planning to consume some, harvest them before flower stalks emerge. Fully grown plants can be over five feet tall. Lower stems and roots on all specimens are a distinctive hot pink color.
This amaranth is a prolific seed producer and will take over a garden if given the chance. It will also depress yields of soybeans, corn and other crops if not controlled. Each plant produces tens of thousands of seeds and they can persist in the soil and be viable for ten years or more. Never throw seed heads in your compost pile.
Pigweed is also resistant to many triazine herbicides used with corn. Many other weed killers aren’t effective either, though numerous ones are. Fortunately pigweed is an annual, so you don’t have to worry about root systems that persist from year to year.
Pigweed is drought tolerant and grows well at warm temperatures in full sun. Removing it before flowers mature is a good control method for homeowners. Pigweed plants are rarely a problem in lawns, because they are mowed regularly and are not allowed to go to seed.
The greens are rich in iron, calcium, niacin, and vitamins A and C. Health wise, there can be a downside, but it’s overrated. Amaranths are high accumulators of nitrates, so on heavily fertilized soils these compounds could potentially reach toxic levels. Nitrate poisoning interferes with our ability to utilize oxygen. It is common in livestock and possible in people under conditions of over fertilization. Nitrate poisoning is also associated with thyroid problems. Old research linked nitrates to cancer, but that has since been disproven.
Many domestic greens like spinach have the same nitrate problem if you can call it that. In small doses nitrates can be beneficial, so don’t worry about the greens unless you know the area received far too much nitrogen. You are much more likely to get a case of Salmonella from domestic greens than suffer nitrate poisoning from eating over fertilized pigweed.
So where is a good place to collect this mild and tender green? I don’t use too much fertilizer in my garden, so there’s a place. Any field not in production is usually a safe bet. Abandoned areas offer great foraging and we have many. We can’t be afraid of everything we might eat since this country imports so much food, particularly fresh fruit and produce. Who knows what other nations use in their farming practices? We have no authority over them nor should we.
Ted Manzer teaches agriculture at Northeastern High School.
ive never seen a plant with red roots and you would never think that this small plant would grow to 5 feet tall
I didn’t know a pig weed could get that tall
its strange i would see these sometimes but i never knew what it was exactly, never knew it was edible either
i different kind of plant. think il pass on eating it though healthy as it may seem.
so that what i chop up the other day by the greenhouses
I’m sorry, but I don’t believe these photos are of Pigweed. I grow Oregano and your photo looks exactly like it.
Oregano has opposite leaves. Those I show are clearly alternate and unmistakably Amaranthus retroflexus. Sorry.