Apios

( AY - pee - ohs )

At-A-Glance Information

This genus, commonly known as Groundnut or Potato Bean, includes species of flowering perennial herbaceous climbing herbs or vining shrubs, several of which have edible roots and fruits. Most species are native to eastern North America as well as eastern and southeastern Asia, including Japan, and prefer to grow in marshes, thickets, along streambanks and in moist forested areas. Grow these plants as ornamental vines for their beautiful foliage and flowers, or as crop plants in areas of the garden that have ample space to fill. Take care when planting Apios in the landscape, as uncooked tubers are toxic to humans and pets if ingested.

Apios Species and Varietals

The genus Apios is a member of the plant family Fabaceae, and includes just 7 species. The best growing zones for Apios plants are USDA hardiness zones 3-9 and Sunset growing zones A1, A2, and 1-22. To find your zone, click here: Zone Map.

Apios americana (American Groundnut, Potato Bean, Hopniss, Indian Potato, Hodoimo, America-Hodoimo, Cinnamon Vine, Groundnut)
These plants are perennial vines that produce edible beans and tubers. Individual plants can reach up to 19.5 feet long and typically produce pink, purple, or reddish-brown flowers in dense racemes. Fruits are pods that reach between 2 and 5 inches long. They are farmed commercially in Japan.

Apios carnea (Apios bodinieri, Cyrtotropis carnea)
These vines are native to Nepal, Bhutan, India, Bangladesh, Myanmar, China, Laos, and Vietnam. They produce green leaves and pink to reddish or flesh-colored flowers that have great ornamental value. Pods that follow blooms can reach up to just over 5 inches long and contain between 12 and 16 seeds.

Apios fortunei (Hodo, Hodoimo, Groundnut, Potatobean)
These plants are cultivated for their tuber roots and their edible bean pods. The species forms a vining climber with green leave and white to green flowers that are sometimes tinted yellow with reddish-purple edges. These plants are native to eastern China and Japan, and are often found near small brooks or streams. Flowers are showy and have ornamental potential, and roots are edible. Vining stems reach up to 6.6 feet long when mature.

Apios priceana (Price's Potato Bean, Price's Groundnut, Traveler's Delight)
This vining plant is native to Alabama, Mississippi, Kentucky, and Tennessee in the United States, where it grows in forest openings near creeks. It grows from a stout, potato like edible tuber and produces green to yellowish pea-form flowers in summertime. Pods are up to 6 inches long. Individual vining stems can reach up to 10-15 feet long.

Caring for Apios

Plant tubers 2-3 inches deep in early springtime. These perennial climbers prefer to be planted in full sun to dappled shade; between 4 and 6 hours of sun per day is ideal. In warm climates, ensure that the vine receives some shade during the afternoon hours to avoid foliage getting sunburned. Check to see if there is enough space in the planting area to accommodate the full size of the vine, which can reach up to 15 feet in length. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 4.5 and 8.5 (acidic to alkaline). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, Apios vining shrubs appreciate consistently moist soil. They are somewhat drought-tolerant, but will perform better and produce better harvests if given regular waterings. As a general rule of thumb, water whenever the top inch or two feels dry to the touch.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Remove spent flower inflorescences to clean up the look of the plant. Apios plants will need to be divided every once in a while to ensure ongoing health. Divide in springtime. For instructions on how to successfully divide Apios plants, see the Propagation section below. These plants have an indefinite lifespan, regrowing each year from underground storage tubers that spread and form colonies over time.

Harvesting Apios Plants
Take care when consuming these plants, as uncooked tubers are toxic to humans and pets. These plants produce edible beans and tuber roots. 2-4 inch long bean pods are produced in late summer or early fall, and are easily harvested by simply picking or cutting them from their attachment to the vine. The beans can be cooked like peas, simply boiled until tender. The tuberous roots are more sought-after as a crop food. They are high in protein (about three times the amount of protein in a potato), and a great source of both calcium and iron. The roots can be harvested in late summer and fall after the plant has died back to the ground. They are best when harvested after the plant has been in the ground for two years. Any sooner and the roots are not as productive, and any later and they begin to get woody and unpalatable. After harvesting, rinse the roots to remove any dirt and debris, and then peel off the skin with a knife or peeler. These roots should not be consumed before being cooked, as they will cause stomach problems. The peeled tubers can be mashed, fried, roasted, or boiled.

Disclaimer: Information contained on this website is strictly and categorically intended as a reference to be used in conjunction with experts in your area. Foraging and consumption of plant parts should never begin without the guidance and approval of a local plant specialist. The providers of this website accept no liability for the use or misuse of information contained in this website.

Propagation

Apios can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your Apios vine, follow the instructions below:

Propagating Apios by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
Harvest your seeds. The seed pods will appear after flowers have faded. To harvest viable seeds, some of the pods will need to be left on the plant to dry out and turn brown. After they have fully dried and begun to open up, they can be taken off the plant and brought inside.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Apios by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil (any kind will do, though it does need to be well-draining), compost, and pots (12 inch pots will do, and these are only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in fall or early wintertime (after the plant has entered dormancy and died back to the ground). To propagate by division, follow these steps:

Dawn your protective gear and gather your materials. Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the tuber roots. Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your gloved fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick tuberous section.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divided tubers about an inch under the soil surface and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it sprout.