The yardlong bean, a variety of cowpea, is a legume with edible green pods that contain immature seeds. It is a vigorous climbing annual vine. The pod of the yardlong bean is pencil-thin, light green, flexible-textured, and pendulous. It begins to form 60 days after sowing, usually hanging in groups of two or more, and can vary in length, from 30 to 80 cm. The best time to harvest yardlong beans is before it becomes fully mature. Growing yardlong bean plants require a trellis to give this plant the vertical support it needs. Yardlong beans have blue or violet flowers when they bloom in mid-summer. The flowers make yardlong beans an ornamental option. The pods and leaves of yardlong bean plants growing in the wild are eaten by animals.
Species: V. unguiculata
Cultivar group: sesquipedalis
Cultivar: Asparagus bean
Yardlong Beans Trivia
- Other names for yardlong beans are asparagus beans, long-podded cowpea, Chinese long bean, Chinese snake beans, bodi/bora, snake bean, pea bean, judia esparrago, haricot asperge, Taao-hla-chao among the Hmong people; jurokusasagemae (Japanese); dow gauk (Chinese); and sitaw (Filipino).
- “Yardlong” is actually a misnomer because the pod is just around half a yard long.
- The subspecies name (sesquipedalis) means ‘one-and-half-foot long’, representing the approximation of the pod’s length
Yardlong Beans Buying Guide
You want to look for yardlong beans with pale green color, because the darker it gets, the more it loses its flavor. Watch for rusty patches because this indicates that the yardlong beans have been poorly stored or have been on display for too long already.
In the US, the best bet when looking for yardlong beans is to visit supermarkets or groceries that specialize in selling Asian vegetables. If you live somewhere where yardlong beans are grown, visit the farmers market or farm stand to see if supply is available.
Yardlong Beans Production & Farming in Texas
Plant yardlong beans in loose, friable soil with a pH range of 5.5 to 7.5. A nitrogen-rich soil is not ideal for yardlong beans because it will cause over-abundant leaf growth and reduce the production of beans. Yardlong beans grow well when under full sun. It can tolerate heat, low rainfall, and arid soils, but at a cost: pods that emerge from this condition are often short and fibrous. It cannot tolerate cold temperatures.
Some farmers harvest yardlong beans with the intention of selling them directly to chefs and restaurants or to local distributors for processing and packaging for later resale. An important note when harvesting yardlong beans: do not pick the buds found above the beans to ensure that the plant can set many more beans in the future on the same stem.
Despite yardlong beans’ popularity and use in Asia, interest in planting yardlong beans in the US is rising, like in Florida where yardlong beans are among the vegetable products being planted to increase and diversify vegetable products here, according to an article published in the University of Florida website. In fact, studies have been made regarding identifying the ideal locations in the US where yardlong beans can be planted, as well as the challenges that cultivation will face and have to address. In Texas, yardlong beans are among the Asian greens being planted by farmers today. The climate and temperature in Texas are ideal for the growing of yardlong beans.
The yardlong bean plant is known to attract pollinators, including wasps and ants. It is also prone to being attacked by aphids, thrips, and mites.
- Kills aphids destroying your yardlong beans using neem oil, insecticidal soap, or horticultural oil. You can also use the pesticide malathion, which is the most commonly used organophosphate insecticide in the United States, or rotenone, a selective, non-specific insecticide typically used in home gardens for insect control.
- Mites – To get rid of mites, use neem oil and apply it through foliar spraying. It contains azadirachtin which is effective against mites. You can also use horticultural oil (which also targets aphids and thrips). Pests die after exposure to horticultural oil due to suffocation since the oil blocks the spiracles through which insects breathe. Another effect of horticultural oils is disrupting the metabolism of insect eggs. Lastly, horticultural oils disrupt the insect’s ability to feed. As a result, the insect starves to death. Using pyrethrin spray is also an effective method against mites. Another option is spinosad, a mixture of two chemicals called spinosyn A and spinosyn D typically used to control a wide variety of pests.
- Thrips – To kill thrips, there is a wide array of options to choose from: horticultural oil, insecticidal soap, anti-parasite spray spinosad, or pyrethrin pesticides with piperonyl butoxide.
The yardlong bean is considered a subtropical – tropical plant based on where it can grow and thrive. The yardlong bean is common in the warmer regions of South Asia, Southeast Asia, southern China, West-Indies, the Mediterranean region, Europe, Oceania, and North America. Food historians theorized that the yardlong beans originated from the Southern Chinese Yunnan province. Yardlong beans have already been mentioned in recorded history, as far back as the Song Dynasty in 1008 CE. Others theorize that Africa is the origin of the yardlong bean, on the account of wild Vigna species found there.
Yardlong beans are commonly sold in the market tied in a bundle. It is placed inside a paper bag or plastic bag upon purchase.
Enjoying Yardlong Beans
The yardlong bean pods are typically crisp and tender when eaten regardless of whether they are already cooked or eaten raw/fresh. They taste like string beans or asparagus. This is generally safe to eat, except for individuals with known immune-allergy to legumes and in G6PD-enzyme deficiency disease (favism).
Yardlong beans will not stay fresh longer if it stays in the open for a long period of time. This is why harvested yardlong beans are kept in cold storage facilities. At home, store yardlong beans the way you would store green beans: put them inside a plastic bag and put this inside the refrigerator. This way, the yardlong beans remain in suitable condition for cooking for at least two to four more days. For winter storage, you can blanch and freeze yardlong beans.
When cooking yardlong beans, the usual practice is cutting these into smaller sections. Like any other vegetables, be sure to wash yardlong beans before preparing them for cooking. Make sure to trim the ends and cut them into desired smaller lengths.
Here are some of the common ways to cook yardlong beans: stir fry with shrimp and potatoes, with soy sauce and garlic, or with chilies and shrimp paste; braised in fish sauce; cooked with mustard and lime; boiled and drained, then seasoned with lemon juice and oil; simmered in butter or oil and garlic; or used as an ingredient in stews in tomato sauce, soups, curries, or salads.
A diet of yardlong beans gives the body fiber that helps in promoting a healthy colon and reducing LDL-cholesterol levels. The folate content of yardlong beans is good, especially for pregnant women. The vitamin C in yardlong beans helps in strengthening the immunity and the body’s ability to fight infection. Yardlong beans also have vitamin A which improves eyesight and skin complexion.