Summer beans – perennials

28 Oct 2021

Part two of summer beans. It’s good to know at a glance which plants are the least amount of work. Perennials that only need planting every few years and generously give food for many seasons make your life so much easier than planting and setting up trellises every year. None of these beans are sold around here as a vegetable so you may not be familiar with any of them.

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Just a quick note on terminology to try and head off any confusion. Beans can be eaten in a number of ways and for some of the beans covered, it matters to get this clear as they can be awful tasting to mildly toxic if they are eaten at the wrong stage in the wrong way.

Whole pods. Beans can be eaten whole, like snowpeas, pod (outside skin) and seed (inside bean) all in one.

Bean seeds. The internal seed you pop out like a shelling pea, once the bean is mature enough.

Seven year beans

Madagascar / tropical lima bean
Phaseolus lunatus syn. P. limensis

Plant one for yourself and your love. Plant another to feed a couple of kids. Another two to help the neighbours on either side out, and then once all the self sown beans have taken off, if you can find your house under the entanglement of vines, you can invite everyone around and feed your neighbourhood. Madagascar bean is prolific at bean making.

This is the number one go-to perennial bean in this area.

Unruly plant. Vigourous. “Needs a sturdy trellis,” said Nell, “Very sturdy!”. Very top heavy vine. Substantial trellis required. Easy to grow. Can get to 6m high and 8m wide, worst case scenario! Like all beans, this doesn’t need major feeding, just trace elements such as seaweed or compost teas.

This rambling and bountiful vine has flat, wide, smooth, thin skinned pods containing a couple of very large cream seeds with reddish-brown speckling. They are quite beautiful and the taste is melt in the mouth creamy. This mature bean MUST BE COOKED for at least 10 minutes boiling. The whole pods can be eaten when quite young but are reported as fibrous. Ditto for the leaves except they are bitter. Skip the pods and leaves. The bean seeds are superb. Pick them at their most succulent when the pod has just filled out and is still green. If you miss that stage, they make a fantastic dried bean for winter that’s large and filling and creamy. Also the seeds can be eaten as sprouts and the cooked beans make a good hommous.

You will probably only need 2 plants to feed a family all year. Like all beans, only 1 is needed for pollination. They don’t necessarily do much in their first year, however after that, look out! The number of beans increases year by year for about a 7 year lifespan.

The stored dried bean lasts 2 – 3 years for seed saving. Plant madagascar bean in the warmer months when the temperature is between 16 to 27°C. It’s best if the soil is above 18°C. Sow the seed 2 – 4 cm deep. It grows very quickly to be ready to plant out. Choose a spot with plenty of sun and soil depth, that doesn’t get waterlogged. It is considered drought proof once established thanks to its very deep root system and is excellent at coping with wet, humid conditions as long as there is enough soil drainage.

You may start to find beans after 12 – 15 weeks. They seem to grow in flushes. It will stay evergreen but slow right down on the coast over winter, but in places with light frost it will die off and regrow again when the weather warms up. Happy feasting!

3 – 5 year beans

Winged bean / asparagus pea / four angled bean
Psophocarpus tetragonolobus

Number two perennial bean. The ‘supermarket on a stalk’ as it is sometimes known. Super nutritious (30 – 40% protein) and underrated and lives for several years. All of the plant is edible – pods, beans, leaves, flowers and even the root (20% protein!). As a bonus, the pods taste similar to asparagus, the flowers taste similar to mushrooms and the root is a sweetish nutty flavoured potato substitute. Monsoonal rains that will destroy annual beans send winged bean into creative overdrive. It has no major pests or diseases here and some resistance to drought. Overwinter the tuber in a 100% frost free spot and it will reshoot all by itself.

Winged beans are a unique shape. They have four wavy wings running down their length. The pods are usually green, sometimes purple, with 5 – 20 beans / seeds. The stems are also usually green, sometimes purplish. Flowers are usually blue, sometimes white to purple. Seeds are usually cream, sometimes brown to purple or mottled. The plant is a well behaved vine, growing to 3 – 4m.

This is one of the world’s most effective nitrogen fixers. Winged bean can develop far larger numbers of nitrogen-fixing root nodules than other legumes. As many as 1,000 nodules have been counted on a single plant, with no need for inoculation as they form partnerships with very common rhizobia. If you don’t eat it, what a green manure! If you do want to try inoculating, it is believed the cowpea strain, type I, is your best bet. It is thought that this amazing nitrogen fixing ability is why the plant is so nutritious for us to eat.

Speaking of eating, the young leaves, flowers, flower buds, pods and tubers can be eaten raw or cooked. The seeds need cooking for 2 – 3 hours.
Use the pods like green beans. They are stringless and have a great flavour. As with many vegetables, younger is nicer. The winged edges harden and become tough and the peas inside do too.
Leaves and young growing tips are said to be delicious raw or cooked and to have a great texture.
Mature seeds can be roasted and eaten like peanuts or ground as a coffee substitute or fermented to make tempeh.
The root is eaten raw or cooked like potato. Tubers are usually 2 – 4 cm in diameter and about 8 – 12 cm long.

The main downside to winged beans in this area (and the subtropics) is that while it germinates fine on its own in it’s home range of the tropics, in cooler places it is a little harder to get going from seed. The soil temperature needs to be a bit higher than for most other beans: 25°C. Lower temperatures suppress germination. It is the last of our summer beans to germinate. Best to sow from October or even better, November and December. Wait for the warm, humid weather before sowing. The seed needs to be treated to have a good rate of germination. It can be scarified (make a break in the hard seed coating by rubbing with sandpaper or nicking with a sharp knife – do this on the opposite side of the seed ‘eye’ so you don’t damage the seed embryo inside). And / or the seed can be pre-soaked in warm water for 12 hours or until the seeds swell. Sow seeds 2.5cm deep, about half a metre apart. In moist soil the seeds swell within 4 – 5 days and germinate within 7 – 14 days. Unusually for a bean the seed only stays viable for a couple of years.

As far as soil goes, winged bean is not fussy. Like every other bean it doesn’t like to be waterlogged. With it’s mindblowing nitrogen fixing it doesn’t need nitrogen fertiliser or rich soil. It will appreciate additional potassium and phosphorus at planting. pH range preference is 5.5 – 7. The most important factor is ample and regular water. This allows it to create the most beans possible. Bear in mind it has come from areas with 2.5m or more of annual rain. We get 1 – 3.5m. Once the plant is large and the roots are deep enough it will cope with short droughts.

The winged bean plant is a bit languid about getting growing. It’s first 4 – 6 weeks it grows quite slowly and you’ll need to keep the weeds away.

As a climbing bean, a trellis is required. Something 1.2 – 2m high, that would suit regular annual beans will do. They will need support right from the start. There’s a recommendation that in the beginning the vines are rather delicate and will only twine around a delicate support. As the plant matures and the vines thicken, the trellis will need to be made sturdier. It’s worth the effort as trellising greatly increases the amount of both seeds and tubers the winged bean plant will create.

The vine will flower from 40 days after sowing. The flowers are mostly self-pollinating, as is typical for beans, but bee visits can give as much as 20 percent cross-pollination. Most varieties of winged bean are sensitive to day length, they need short days (11 – 13 hours of daylight) as well as warm weather (not below 18°C at night, 25 – 32°C days) to trigger flowering. That’s up to November, and from February for us. Look out for the variety hunan, which is not sensitive to day length.

Continuous temperatures below 18°C and above 32°C will inhibit flowering, even if the day length is right. By April we are regularly getting temperatures below 18°C, so that’s the end of winged bean season. On the bright side, the plant will make more tuber at lower temperatures.

The best time to be picking leaves for eating for your tastebuds and the health of the plant is before flowering.

Depending on the timing of planting and day length, the pods can be ready to eat with 2 – 3 months. The pods develop in two stages. First the pods grow to their full size of over 20cm long and over 2cm wide, which takes about 2 weeks after pollination. This is the time to pick them for eating whole, while they are tender. Pick all the pods when they are small to keep the plant creating more. After 3 weeks the pods become fibrous and are no longer flexible enough to bend without breaking. The second stage the seeds are growing, hardening and becoming mature while the pod shrivels. This is complete after about 6 weeks. If picked early in this stage the soft green seeds can be shelled and used like peas. Otherwise once hardened they are mature.

The first year is when winged bean will make the most number of pods and seeds. Picking the pods stimulates the tuber to grow. Growing out the pods for seed reduces the tuber amount. Tubers can be harvested from 5 months after sowing. This will kill the plant. But, winged bean makes much more tuber in it’s second year. So, logically, pick as many pods and seeds as you want in the first and maybe second years. In the final year, pick all the pods and don’t leave many to go to seed and dig up and enjoy the tuber. The plant lives at least 3 years.

Winged bean will die back in winter. The tuber becomes dormant. It will resprout when the warmth and wet are high enough. Be aware that it almost never survives frost.

Big thanks to:
Michele Morozumi, Phil & Carol Helman, Jeff Alcott, John Vernon, Susan Doyle, Tim Hill, Nick Radford, Nell Heydon, Alison Heeley

Supported by Bellingen Shire Council via the Bellingen Shire Disaster Recovery and Resilience Grant Program Funding

Notes

Beans

1. Fanton M& J. The Seed Savers Handbook. The Seed Savers’ Network; 2008.

2. Inoculating Legumes: a practical guide. Grains Research & Development Corporation; 2013.

3. GoodBadBug-FINALscreen22Feb3.pdf [Internet]. [cited 2021 Oct 13]. Available from: https://thebeatsheet.com.au/wp-content/uploads/2012/04/GoodBadBug-FINALscreen22Feb3.pdf

4. Legume-Inoculant-Selection-Chart-green-rhiz.pdf [Internet]. [cited 2021 Oct 19]. Available from: http://greenmicrobes.com.au/wp-content/uploads/2018/02/Legume-Inoculant-Selection-Chart-green-rhiz.pdf

Madagascar bean

1. perm mullum. perennial madagascar bean [Internet]. 2011 [cited 2021 Oct 22]. Available from: https://www.youtube.com/watch?v=xjEfpX4Y5oc

2. Lima bean. In: Wikipedia [Internet]. 2021 [cited 2021 Oct 22]. Available from: https://en.wikipedia.org/w/index.php?title=Lima_bean&oldid=1049734870

3. Bean Madagascar, Phaseolus lunatus [Internet]. Daleys Fruit. [cited 2021 Oct 8]. Available from: https://www.daleysfruit.com.au/Bean-Madagascar-Phaseolus-lunatus.htm

4. Lima Bean “Madagascar Bean” [Internet]. Succeed Heirlooms. [cited 2021 Oct 8]. Available from: https://www.succeedheirlooms.com.au/pulse-dried-bean-seeds/lima-bean-madagascar-bean.html

5. Lima bean (Phaseolus lunatus) [Internet]. Feedipedia. Available from: https://www.feedipedia.org/node/267

6. Madagascar Bean Growing Information [Internet]. Green Harvest. [cited 2021 Oct 8]. Available from: https://greenharvest.com.au/SeedOrganic/VegetableGrowingInformation/MadagascarBeanGrowingInformation.html

Winged bean

1. Bassal H, Merah O, Ali AM, Hijazi A, El Omar F. Psophocarpus tetragonolobus: An Underused Species with Multiple Potential Uses. Plants. 2020 Dec;9(12):1730.

2. Winged bean. In: Wikipedia [Internet]. 2021 [cited 2021 Oct 18]. Available from: https://en.wikipedia.org/w/index.php?title=Winged_bean&oldid=1032922641

3. » WINGED BEAN [Internet]. Byron Hinterland Seed Savers. [cited 2021 Oct 26]. Available from: https://byronseedshare.org/perennials-foods/winged-bean/

4. Climate Data Online – Map search [Internet]. [cited 2021 Oct 28]. Available from: http://www.bom.gov.au/climate/data/?ref=ftr

5. Organic Vegetable Seeds Online – Beans [Internet]. Green Harvest. [cited 2021 Oct 26]. Available from: https://greenharvest.com.au/SeedOrganic/VegetableSeeds/Beans.html

6. Seed Scarification Techniques – How To Nick Flower Seeds Before Planting [Internet]. [cited 2021 Oct 28]. Available from: https://www.gardeningknowhow.com/garden-how-to/propagation/seeds/nicking-plant-seeds.htm

7. Sunrise and sunset times in Bellingen [Internet]. Time and Date. [cited 2021 Oct 28]. Available from: https://www.timeanddate.com/sun/@7839692

8. The Winged Bean (1981): 2 Agronomy [Internet]. Humanity Development Library. [cited 2021 Oct 26]. Available from: http://www.nzdl.org/cgi-bin/library?e=d-00000-00—off-0hdl–00-0—-0-10-0—0—0direct-10—4——-0-1l–11-en-50—20-about—00-0-1-00-0–4—-0-0-11-10-0utfZz-8-10&a=d&cl=CL1.19&d=HASH20b4d9b2b5ae925732357e.4

9. Winged bean, Psophocarpus tetragonolobus [Internet]. Grow Florida Edibles. [cited 2021 Oct 26]. Available from: https://www.growables.org/informationVeg/BeanWinged.htm