since you asked: apios americana, the potato bean or groundnut
JULIE, WHO GARDENS in the same Northeast area that I do, wrote in to ask: “I have been very intrigued by the potato bean since reading about it in ‘Wired’ magazine. What do you know about them? Seems they should be indigenous to our part of the world.”
Julie is referring to Apios americana, a native nitrogen-fixing legume that I was told was Apios tuberosa when first introduced to it (those are some dug-up tubers, above). It’s also called groundnut, and potato bean. And yes, they are native up into New England, but many invasive plants have shoved them out of their favored range (this older “Orion” magazine piece talks about that).
new feature: ‘since you asked’
I SPEND MANY HOURS each week trying to answer reader questions, which arrive in email and comments in such large numbers that I cannot keep up, I am sorry to admit. But I do manage to answer some, which led to this thought:
Why keep the replies hidden, between me and the individual questioner, I figure, so here we go: a new feature called “Since You Asked” that shines a light on the “best” questions—which might mean most practical, or most timely, or simply the oddest one that appealed to me who knows why.
I’ll “tag” all the entries at this link to make a stockpile of them for future reference; this is the first.
THE WIDELY adaptable groundnut has an impressive native range, in areas from temperate to sub-tropical (see the USDA range map), in Zone 4-9. It will even grow in places like cranberry bogs (growers often consider it a weed). It’s usually found in moist areas, where at least part-day sun is available.
I have seen Apios growing in the wild once or twice, and a million years ago in a friend’s garden, too; it was something she inherited, I learned, with her very old house in Connecticut, and it was just always there, climbing enthusiastically by the shed, so she went with the flow.
I say “enthusiastically,” and various Apios references say “not well-behaved,” but even though it’s a strong grower, invasives have pushed it from many former haunts, as mentioned.
If you have a spot to give it where its enthusiasm is not at issue, as in a space of its own in a fringe area, Apios (which may reach 20 feet, but probably less) is a pretty plant in flower. Vine expert Dan Long of Brushwood Nursery (who offers the plant for sale) says that at first glance, you think: red wisteria!
“I first saw this growing in the wild while kayaking with the family on Broad River in Georgia,” he recalls. “My first thought was, ‘look at that marvelous red Wisteria!’”
- Apios grows in “moist thickets,” says the Connecticut Wildflower Society, on herbaceous vines reaching up to 10 feet, flowering summer-into-fall there.
- Early colonists, notably in Massachusetts, relied on this native plant’s highly nutritious tubers for their survival.
- They were inspired by Native American people, who had long utilized both the bean-like seeds and the tubers, including to make flour.
- A crude protein content of 11-16.5 percent of dry weight in tubers, and 25 to 30 percent for seeds, has been reported in various studies. (That would make the tubers as much as three times as protein-rich as potatoes.)
- The tubers, produced like beads along strands of rhizome, can be eaten boiled, fried or roasted.
- The plant’s foliage is one larval host for the silver spotted skipper.