🫘 Yardlong Bean

What it looks like

How to grow

Yardlong bean — also called asparagus bean, snake bean, or Chinese long bean — is a vigorous climbing cowpea grown for long, slender, stringless pods. Direct-sow after all danger of frost, when soil is at least 65–70°F; cold soil rots the seed. Sow about an inch deep, 4–6 inches apart, at the base of a sturdy trellis at least 6 feet tall — these vines are heavy and need real support. They are heat-loving and frost-sensitive, thriving at 77–95°F, and they fix their own nitrogen, so inoculating seed with cowpea-type inoculant helps on ground where cowpeas have never grown. In short-season climates, start seed indoors only if you can transplant without disturbing roots, or choose the earliest variety you can find.

Water & feeding

Water deeply at the base, about an inch a week, and more during flowering and pod formation; dry soil at flowering gives low yields and fibrous pods. Do not over-fertilize with nitrogen — you will get leaves instead of beans. Compost at planting and a low-nitrogen side-dress when pods form is plenty.

Common problems

• Cold, wet soil — wait for warm soil; seedlings collapse in cold ground.
• Aphids and bean beetles — row cover early, hand-pick, and encourage ladybugs.
• Rust and mildew in humid weather — space for airflow, water at the base, and remove badly affected leaves.
• Tough pods — you waited too long; pick young and pick often.

Harvest

Pick pods when they are 12–18 inches long, still slender, firm, and flexible, before seeds bulge — about 60–80 days after sowing. Harvest every 1–2 days; frequent picking keeps vines producing for 6–8 weeks. Snip pods into short lengths and stir-fry, dry-fry, or add to curries. Like most beans, yardlong beans are best cooked, not eaten raw in quantity.

Saving seeds

Yardlong bean seed is easy. Let a few pods ripen on the vine until they are dry and brown and the seeds rattle inside, then shell them into a paper bag. No cold treatment is needed; sow in spring once the soil is warm, in moist soil, about an inch deep, and keep it warm — germination usually comes in one to two weeks.

Save seed from the best vine — the longest pods, the heaviest yield, the healthiest leaves — and dry the seed thoroughly before storing; it keeps four to five years in a cool, dry jar. A single vine makes dozens of pods, so one plant is enough for a whole bed next year.

Yardlong bean is self-pollinating, which makes pure seed easy — but it crosses with other cowpeas, so grow only one cowpea type for seed at a time if you want it pure. And a note: the pods are best picked young and tender, so let only a few pods go to seed and eat the rest.

In Florida, yardlong bean is a warm-season vine for spring through fall, happiest in full sun and rich, moist soil. It is a tropical legume that loves the heat and the humidity, and a vine grown from your own seed is a plant that knows your garden.

Varieties

Every named variety of Yardlong Bean with its own growing guide:

• Chinese Green Noodle Yardlong Bean — The most productive yardlong in trials — bright green, very tender, mild pods, and a heavy bearer.
• Chinese Mosaic Yardlong Bean — The lavender-pink yardlong — early, productive, and the second-highest yielder in trials.
• Red Noodle Yardlong Bean — The bean that refuses to be measured in inches: burgundy-red pods up to 22 inches long, on a vine that laughs at heat, humidity, and poor soil. (already on this site; listed here, not rebuilt)
• Orient Wonder Yardlong Bean — The classic long bean: dark-green, stringless pods up to 30 inches that stay tender because the seeds are in no hurry.
• Thai Purple Podded Yardlong Bean — The purple showpiece: deep-violet pods, heat-and-humidity tough, that hold their color in the stir-fry pan.
• Liana Yardlong Bean — The day-neutral early bird: producing in about 70 days regardless of day length — and the fall-crop pick for warm climates.
• Red Seeded Yardlong Bean — The Southeast Asian yardlong — slender green pods up to two feet long that thrive in heat and humidity.