A delightful, delicious, and nutritious addition to any food garden, Chinese noodle bean is a warm-season crop that produces an abundant harvest of long, slender pods. Native to subtropical and tropical parts of Africa and Asia, the plant is widely grown in southern China and the Philippines, but is a relative newcomer to US gardens. Its popularity will surely grow as gardeners of all ages try this fascinating plant with its impressive vines studded with lovely blooms and draped with countless crazy-long pods!
- Sometimes called “yardlongs,” the beans are generally half that length —16-20”.
- The botanical name is Vigna unguiculata Sesquipedalis and it tells us many things about the plant:
- The genus nameVigna honors Italian botanist Domenica Vigna.
- The species nameunguiculata is Latin for "claw" and refers to small structures on the flower petals.
- Sesquipedalisis Latin for "foot and a half long" — a closer approximation to the beans’ true length.
- The “subsp.” is an abbreviation of “subspecies,” indicating that Chinese noodle beans are a subspecies of Vigna unguiculata, the cowpea, also known as black-eyed pea, southern pea and crowder pea.
- Other common names are asparagus bean, and Chinese long-bean, snake bean, long-podded cowpea.
- The vigorous vines can reach 9-12’ high and are quite ornamental, with purple blossoms and long, draping pods.
- Legumes like these “fix” nitrogen and store it in their root nodules, leaving some behind for subsequent crops. This makes them an excellent choice for crop rotations with nitrogen-hungry crops like corn.
- Chinese noodle beans are nutritional powerhouses. They are good sources of soluble and insoluble fiber, vitamins A and C, folate, magnesium, and manganese.
How to Grow Chinese Noodle Beans
Site and soil. Choose a location in full sun with deep, well-drained soil. Tall raised beds are a good choice because they warm up and dry out earlier in spring than in-ground beds. A location protected from strong winds is ideal.
Loosen the soil to a depth of at least 12” and amend the soil with compost. This allows the plants to readily produce their robust and extensive root systems — a feature that helps them tolerate hot, dry conditions. You can also add a slow-release, granular fertilizer, but be careful not to use a high-nitrogen fertilizer, or you’ll get lots of foliage at the expense of beans.
Like other legumes, the plants fix nitrogen; that is, through association with soil bacteria they absorb nitrogen from the air, change it into a form usable by plants, and store it in small root nodules. Although the plants’ nitrogen-fixing soil bacteria partners are naturally occurring in many soils, some gardeners apply a commercial inoculant to boost its population.
Install a trellis or other structure. The robust vines require a sturdy place to climb. Keep in mind that you’ll need to reach the top to harvest, so a trellis or fence that’s about 7’ high is a good choice. The stems climb by twining, so uprights can be up to 1-1/2” in diameter. The plants will become top-heavy when laden with beans, so be sure the structure is securely anchored and won’t topple.
Planting. Wait until all danger of frost is past and soil has warmed. Soak the seeds overnight to speed germination.
Though Rhizobium bacteria — the soil bacteria that help the plants fix nitrogen — are naturally occurring in many soils, some gardeners apply a commercial inoculant to the soil prior to planting.
Plant the seeds 1” to 2” deep around the trellis or along the fence, spacing them about 3” apart. Once seedlings are up, thin them to 6” apart by snipping off the weaker seedlings. The plants prefer hot, sunny weather and may get a slow start in cool temperatures.
As the plants grow, gently train them to their support, if necessary, by loosely winding the stems around the uprights or tying them with small strips of soft fabric. Be very gentle; if you damage a stem, you’ve may have lost a plant.
Growing on. Weed the beds frequently to remove competition for water and nutrients. Once the soil has fully warmed, you can apply a layer of straw mulch to conserve moisture and discourage weeds.
Water the beds to keep the root zone moist. Early in the season, this may mean watering twice a week. Later, it could entail a much deeper soaking. Drip irrigation and soaker hoses are good choices. Though the plants will tolerate some drought, they’ll produce a bigger and better crop with regular watering.
If soil was amended with compost and a slow-release fertilizer, the plants may need little or no supplemental fertilizer. Otherwise, every few weeks apply a low-nitrogen organic fertilizer.
The plants have few pests, and aren’t bothered by bean beetles, a notorious pest of green beans.
Harvesting. Keep an eye out for the beautiful blossoms, which may be purple, deep red, or violet-blue depending on the variety. Under ideal conditions, you’ll begin harvesting about two months after planting.
Harvest young, smooth pods when they’re less than ¼” in diameter — before you can see the bulges of the developing seeds inside. Use these fresh in salads, lightly sauté, or steam them.
Slightly larger beans — the thickness of a pencil — are ideal in stir-fries, casseroles, soups, stews, and in any of the many recipes for you’ll find online.
Harvest beans regularly (even daily!) and the plants will continue to produce until cool weather shuts them down and frost kills the vines. If too much time passes between harvests and pods begin to produce fully mature seeds, that will signal the plant to stop producing new beans. Fortunately, you can also eat the seeds, too. Pop them out of the pod and either cook them fresh or dry them for later use.
Donn Meade was a gardener, designer, and sculptor. His sense of creativity is evident through all aspects of his garden. He shied away from the ordinary when it came to his garden, creating statement accents by hand from discarded materials and loved to grow things you couldn’t find in the grocery store. It’s in his memory that we bring you this growing guide for Chinese Noodle Beans.