Once you have mastered the standard vegetables most gardeners grow, you may want to branch out into lesser-known, heirloom edible plants.
Taking a leaf out of our ancestor’s book or trying something new is a rewarding challenge and introduces you to food you might never have tried.
Often, uncommon plants aren’t overly palatable or easy to grow because they haven’t been extensively cultivated like modern favorites. But American groundnuts (Apios americana) are delicious and easygoing, and you can eat the whole plant!
Ready to learn more?
What is Apios Americana?
Apios americana is indigenous to North America and is a staple of Native people in the region where it grows. The tubers, shoots, and beans are all edible.
As European settlers arrived, they were introduced to the plant by native people and began growing it. It’s credited as one of the foods that helped settlers survive those first few winters when food was scarce.
It’s perfect for a food forest or survival garden. It’s a hardy perennial vine that grows up to 16 feet long and only takes two years to provide a harvest. It might produce a small crop in the first year, especially if you grow an improved cultivar.
These lovely plants are in the pea family (Fabaceae) and are also known as Americ-hodoimo, potato bean, cinnamon vine, hodoimo, wild potato, or hopniss.
A. americana is like the potato (Solanum tuberosum), but with a nuttier flavor. It’s delicious and easy to grow, so it’s a shame that people don’t cultivate it much.
The bean-shaped fruits that form are edible once cooked, but the star of the show is the tuber, which contains more protein than potatoes and lots of calcium and iron. Also edible are the new growth shoots and flowers, which you can eat raw.
Treat the tubers like potatoes and add them to stews, fry them, or make a nutritious soup.
On top of all of these nutritional benefits to you, American groundnuts are also beneficial to your soil. It is a nitrogen-fixing legume that replaces nitrogen in the garden.
Cultivars of Apios Americana
You can forage for wild A. americana to grow, but there are improved cultivars available, so see what you can find from sellers. Some of the named cultivars are:
There are 43 improved varieties by the Louisiana State University (LSU) that are generally given numbers instead of names in their breeding program.
Be sure to look for the botanical name when shopping since this plant goes by so many names, and there are lots of other plants with similar names.
Propagating Apios Americana
The easiest way to propagate American groundnuts is by tuber division. You don’t need to use the whole string of tubers that form. One is sufficient, though save a few just like you would seed potatoes.
You can harvest in the fall and save any you want to replant until next spring when the ground thaws in cold areas.
Put slightly damp (but sterile) soil in a plastic bag. Bury the tubers in the soil and seal the bag. Make sure to put some holes above the soil line to enable the contents to breathe.
Store the whole thing in the refrigerator. Once they start sprouting, you can plant them (assuming the weather is appropriate). Let’s talk about planting next.
How to Plant Apios Americana
Let’s look at the growing conditions of A. americana in the wild and where you will find them when foraging.
It can be found in non-tidal and tidal marshes, the banks of streams, and bottomland forest areas that are generally damp. It grows anywhere from moderate shade to full sun, though the flowering and tuber production is smaller in shaded spots.
You can grow A. americana in USDA Growing Zones 4-9.
Plant two-year-old tubers about three inches deep in the spring. This plant doesn’t like competition when it’s young, though that’s not an issue as it ages, when it can become weedy. Mulch well to prevent weeds from competing for space.
Add well-rotted compost to the soil and dig it in deep. The area must be well-draining but able to hold a little moisture. Aim for a pH of around 5.0 to 7.5.
Plant American groundnuts in full sun or an area with some afternoon shade. Dappled sunlight is okay, though your harvest will be reduced. An area protected from wind is best. In scorching areas, afternoon shade will be necessary.
Plant about 12 inches apart.
In cool areas, trellis this vine against a sunny wall. Provide support for the vine to climb up or plant where the vine can grow naturally, like close to trees or shrubs.
It takes up little space along the ground as it likes to grow up and over things.
When to Plant
Although the tubers are cold-tolerant, ensure the soil is workable and any predicted frosts are done in early spring. If your region gets very cold in the winter, use thick layers of mulch to keep the tubers a little warmer.
Growing American groundnuts in containers is a great way to grow this plant for a few reasons. It’s a vine that appreciates being trellised, so against a wall in a container, allowing it to grow up supports is perfect. This wood container with a built-in trellis would be ideal.
The rhizomes under the soil can spread after a few years and become too much, so a pot keeps it contained.
In smaller areas, on patios or balconies, it needs a container. Apart from being a food source, it can also be a focal point, especially when the beans and flowers form.
Use a large, five-gallon container or bigger filled with quality potting mix that drains well. Big canvas plant bags work well. Or use old tires as you would for growing potatoes.
You can plant A. americana seeds, but this method is unreliable and will likely not be true to the parent plant. Also, it adds to the time it takes for you to be able to harvest any of the wonderful tubers.
Planting tubers is a much better idea, but feel free to go with seed if you have the time and don’t mind what you end up with.
Caring for American Groundnuts
American groundnuts are not a demanding plant, given their wild origins, but you must make sure they get enough water. If this doesn’t happen, the pods that grow are likely to be hollow or to contain shriveled and dried beans inside, and the tubers will be small.
Because A. americana is a nitrogen-fixing plant, it can survive without being fed, but if you want the best crop and to be able to leave some tubers in the ground for next season, provide a little fertilizer.
Add a well-balanced fertilizer or well-rotted compost when planting, and you shouldn’t have to add any more.
Water regularly so that the soil is constantly moist, but don’t allow the water to sit or for the area to become waterlogged. The tubers will rot if the soil is saturated.
Although you don’t want the soil to dry out, don’t overwater. If in doubt, water deeply but infrequently. As soon as the surface begins to dry, water again. The soil should feel like a well-wrung-out sponge.
Companion Planting For Apios Americana
You can grow Apios Americana without support, but it will provide bigger yields when it climbs up support like a trellis or fence. It will die back in the winter and will return the following spring. Try growing American groundnuts with:
Common Problems and Solutions for Growing Groundnuts
Left to their own devices, American groundnuts are fairly maintenance-free. That’s one of the best things about growing native plants that are largely uncultivated. You might run into problems here are there, especially if you don’t provide the right growing environment.
Leaves or Vine Dies Back Early
This is usually due to frost damage. The plant will survive even the coldest frosts, but the greenery won’t. When the weather warms, the plant will come back as the roots and tubers are underground and protected.
Mulch in cold areas to help keep the parts of the plant under the ground nice and warm.
The leaves may show signs of stress and drop off if the plant is over-watered or under-watered.
Dieback or Yellowing of the Leaves
Search around the base of the plant and look for signs of digging. Unfortunately, the tubers are loved by both mice and gophers.
Use a liquid repellent or whatever method you prefer to use.
No Seed Pods
There are two types of American groundnuts: triploid and diploid.
Diploid produces seed pods; triploid types produce flowers but no seeds. Either way, you still get the yummy tubers from both.
Slugs and Snails
Although they won’t do too much damage unless in large numbers, slugs and snails can be a pest. Use pellets or any of your other favorite methods to keep them away.
Harvesting and Storing American Groundnuts
Wait until the plant dies back in late summer or fall in the second year. Harvesting before this will result in unusable tubers that are soft or unpleasant to taste.
In the second year, the plant can grow a ton of vines, making it hard to find the tubers underneath.
To find them, follow the vine to where it enters the ground. Dig carefully so you don’t damage the tubers. Some will be close to the surface, and some will be deeper.
The tubers form on a chain, each connected to the other by a thin, woody rhizome. The chain could be anywhere from two or three to over 20 tubers long.
In warm areas, leave some of the tubers and rhizomes in the ground, and they will regrow. Unlike potatoes, American groundnuts take two years to produce a big harvest, so stagger planting and harvesting.
The tubers will vary in size from very small to comparable to a medium potato.
Store the tubers like you would a potato. Place them in a cardboard box or paper bag in a cool, dark place, and they will last for months.
Cooking American Groundnuts
Treat just like a potato with one caveat. Don’t put American groundnuts in a dish with powerful flavors, or you won’t be able to detect that nutty flavor. They are bit drier than potatoes, so they cook faster. Cook them in larger slices or whole.
To eat the seeds, shell them and cook them. The flowers can be eaten raw.