Long Bean Trial — 2007

Garden Help > Vegetables > Beans

Summary

We compared 12 varieties of long beans, Vigna unguiculata, to determine which ones have the best production and the best flavor for growing here in Santa Clara County. Chinese Green Noodle was the most productive variety by far and was the favorite in the first tasting for its very tender, mild pods. Chinese Red Noodle was a favorite for those who like beans with a richer flavor and a firmer texture and was a good producer. All activities were conducted at out Nine Palms growing facility.

Soil preparation

The plot had previously been used for a raspberry trial. In May we finished removing the raspberries and rototilled in four inches of compost.

Arbor

We created an arbor structure for the beans to climb by bending 16-foot lengths of five-foot wide concrete reinforcing wire into an arch and lashing them to eight-foot posts that had been driven one and one-half feet into the ground. The arch is 4 feet wide, 7 feet high in the center, and 35 feet long. The one-foot wide planting beds are mounded slightly, about six inches higher than the center of the pathway. The concrete reinforcing wire has a 6-inch mesh.

 

The bean arbor in May, 35’ long, 4’ wide, 7’ high
The bean arbor in May, 35’ long, 4’ wide, 7’ high

 

In the Arbor on August 10
In the Arbor on August 10

Seeding and transplanting

We planted the beans directly into the ground on June 1, two beans per hole, six inches apart, and thinned them after two weeks to one seedling every six inches. There were eight vines of each variety, four vines on each side of the arbor so they could grow up to the center and meet. There was a one-foot gap between varieties.

The planting order was the same on both sides of the arbor. We attempted to alternate the pod colors for ease of harvesting, although the pod colors weren't known for all varieties. From south to north (front to back), it was:

Taiwan Black (light green) 
Chinese Mosaic (lavender-pink) 
Black Stripe Seed (light green) 
Chinese Red Noodle (deep red) 
Thai Red Seeded (green) 
Canton White Pod (light green) 
Kaoshiung (dark green) 
Red Stripe Seed (light green) 
White Seed (light green) 
Surinam Asparagus Bean (green) 
Red-Seeded Asparagus Bean (deep red) 
Chinese Green Noodle (bright green)

Watering

Irrigation was set to 45 minutes, three times a week.

Fertilization and pesticides

No additional fertilizer was used. No pesticides were used.

Harvesting and observations

Harvesting began on August 7 with Chinese Mosaic and Chinese Green Noodle. Our last harvest was September 28, and the vines were removed on October 2. The biggest producer, by far, was Chinese Green Noodle, followed by Chinese Mosaic and Chinese Red Noodle.

Clusters of Chinese Mosaic long beans
Clusters of Chinese Mosaic long beans

Long beans mature quickly and need to be picked every few days so they don’t become over mature and tough. In general, they should be picked while still slender, before they get puffy and the seeds become visible. Thai Red Seeded and White Seed were two varieties that could be allowed to get a little fatter and meatier than the others while still remaining tender.

We harvested through Sept 28, although at that point most varieties were producing a few ounces or less. Only Canton White Pod (10 oz) and Thai Red Seeded (13 oz) were still producing more than minimal amounts that final day.

VarietyTotal 
production 
in ounces
First 
harvest
Last 
harvest
Pod 
color
DescriptionSource
Black Stripe Seed23.54-Sep28-SepLight greenVery branching at bottom, vigorous growthEvergreen
Canton White Pod58.54-Sep28-SepLight greenLighter green leaves, short beansEvergreen
Chinese Green Noodle212.57-Aug28-SepBright greenVigorous growth, big producerBaker Creek Heirloom Seeds
Chinese Mosaic135.57-Aug21-SepLavender-pinkEarly production on lower branching vinesBaker Creek Heirloom Seeds
Chinese Red Noodle134.524-Aug25-SepDeep redVigorous, dark green leavesBaker Creek Heirloom Seeds
Kaoshiung0.528-Sep28-SepDark greenShort vines, never really produced, mosaic virusEvergreen
Red Stripe Seed44.531-Aug28-SepLight greenSigns of mosaic virusEvergreen
Red-Seeded Asparagus Bean82.521-Aug28-SepDeep redShort and concentrated productionBaker Creek Heirloom Seeds
Surinam Asparagus Bean5824-Aug28-SepGreenCurly beansBaker Creek Heirloom Seeds
Taiwan Black84.2524-Aug28-SepLight greenVery long beansBaker Creek Heirloom Seeds
Thai Red Seeded82.7521-Aug28-SepGreenVery vigorous vines and dense foliageBaker Creek Heirloom Seeds
White Seed62.2528-Aug28-SepLight greenLighter green leaves, signs of mosaic virusEvergreen
 
All 11 varieties that produced, on 9/7/07

Tasting

We conducted two tastings. The first one was on Aug 24 with the five varieties that were producing at the time (Chinese Green Noodle, Chinese Mosaic, Chinese Red Noodle, Red-Seeded Asparagus, and Thai Red-Seeded). The second tasting was on September 18, with all varieties except Kaoshiung, which only produced one pod at the very end. For both events, Jean individually stir-fried samples of each of the varieties in a hot wok with oil, a little salt, and some water to steam. People were welcome to taste the beans raw as well if they wanted to.

VarietyFirst tasting votesSecond tasting votesComments
Black Stripe SeedNone to taste11Sweeter than others
Canton White PodNone to taste3Nice flavor
Chinese Green Noodle110Very tender, mild, good taste. Very similar to the long bean widely available in San Francisco Chinatown, perhaps due to its high yield. (For the second tasting, this variety was past its prime.)
Chinese Mosaic12Turns dark green when cooked, nutty flavor, firmer texture, not sweet
Chinese Red Noodle74Rich, deep flavors, chewy. But some people disliked the firmer texture, calling it tough.
KaoshiungNone to tasteNone to taste 
Red Stripe SeedNone to taste6Deep flavor, meaty, lingering flavor
Red-Seeded Asparagus Bean63Almost as tender as Green Noodle, crisp, nutty
Surinam Asparagus BeanNone to taste5Asparagus-like flavor when raw, grassy, a little tough
Taiwan BlackNone to taste0A touch bitter, grassy, not meaty, tender after cooking
Thai Red Seeded02Heavy flavor, not as sweet as others, very tasty, sweet, meaty. Can be picked at a larger diameter, resulting in sweeter, meatier beans.
White SeedNone to taste1Very sweet, meaty if allowed to develop, very tender

Pests & diseases

Ants were present on the vines and flowers. They did not appear to be causing any damage but were merely visiting the extrafloral nectaries present on the flowers.

Red Stripe Seed, White Seed, and Kaoshiung varieties showed signs of bean mosaic virus from the start, so I suspect the seed was infected. We didn’t do anything, although in retrospect perhaps we should have taken out the infected vines so the virus wouldn’t be spread to any others. We didn’t save seed from any of the varieties due to the presence of the virus in the plot.

 

Long bean flower with ant
Long bean flower with ant

 

Bean mosaic virus on Kaoshiung variety
Bean mosaic virus on Kaoshiung variety

Conclusion

Chinese Green Noodle was the most productive variety by far and was the favorite in the first tasting for its very tender, mild pods. Chinese Red Noodle was a favorite for those who like beans with a richer flavor and a firmer texture and was a good producer. Black Stripe Seed was rated highly for flavor but was a poor producer.

 

Lead: Karen Schaffer
Team members: Jean Lee, Ken Lee, plus assistance from many Nine Palms regulars


Source URL: https://class.ucanr.edu/site/uc-master-gardeners-santa-clara-county/long-bean-trial-2007