Friday 4 May 2012

What is this plant with beans called?

It's just down the street, on the corner, and I walk past it every day. In early springtime there is a flood of yellow flowers. These have now mostly morphed into these bean-like pods hanging off the plant. A few of the flowers remain, but most of them were pollinated by insects, probably bees, and have turned into pods full of seeds.

The reason I took this photo is not just to find out what the plant is called. It's also because of the recent story about the vanilla bean market, which is unhealthy globally giving Australian vanilla growers opportunities to make some extra money. I wrote about vanilla in 2010 through a contact at the University of Western Sydney and so I keep an eye open for stories about this strange pod.

Just growing the beans themselves is a challenge, especially at pollination. Vanilla is an orchid and commercial vanilla is pollinated manually. In their native Mexico, vanilla flowers can be pollinated by a bee of the Melapona family, but the main countries producing vanilla are Madagascar and India. Regular European honey bees cannot negotiate the vanilla flower's complex shape. Getting vanilla flowers to produce beans is a fraught process.

When stressed, which can be done by withholding water from the vanilla vine, racemes emerge in the axils at the base of the leaves. Each raceme produces 15 to 30 flowers and if they are not pollinated immediately the flowers die. Every day only one flower opens on the raceme. Fussy flowers!

But the yellow flowers down the street from my place are not fussy at all and respond plentifully to the ministrations of regular European honey bees. The pods emerge well before summer. No doubt vanilla growers would love it if their plants were as easy to make fruit as this one. Do you know what it is?

[UPDATE 4.25pm:] It's a weed called Easter cassia.

11 comments:

Unknown said...

Did you get a response on the name of this plant? I have the same plant at my unit and need to find out the name. Phil (cpclarke@gmail.com)

Unknown said...

I have one yoo I want to know if I can eat it

Scott said...

I have this exact same plant in my yard. It is definitely not a vanilla bean plant of any variety. But also I can not connect it to any kind of green bean or string bean.

Sonia said...

It’s an Easter cassia , I believe it’s a weed I have one too

Aria said...

I doubt it’s a Easter cassia since I also got this plant, the flowers are slightly different. Also they do actually have beans my mom says later on we can eat them but idk about that.

Kropkut said...

Well,recently my mom goes for the dried pods crunks out the beans and do some dry frying or whatever it is.....She adds water and makes it settle for sometime..

And Holy holy it smells and tastes like coffee......

She claims, it helps reduce her stress and anxiety....She has a high BP and cannot do a lot of hard work but this has caused total change.....Still waiting to see if there're side effects tho.

Anonymous said...

Esperanza

Anonymous said...

Ive returned to say, she's fine and healthy by God's grace

Anonymous said...

I have this plant Durban
and the monkeys eat the pods.

Anonymous said...

Still no name yet

Anonymous said...

The one in my yard is Easter Cassia or Senna pendula: variation is glabrata.. it originates in Australia and is common in Brisbane, Cairns, and Queensland area. I live in central FL. I found it online at Roger's Gardens, with photos exactly like my plant and descriptions of when it flowers and produces beans and the leaves are dark green with lighter veins in them. It says foliage is an evergreen . I tucked it under my large eves to the house last winter and covered when it froze. I saw either here or someplace that it grows in climate 9A..It grows very fast and is invasive but mine has not spread to other places like my Pagoda plants which also are frequented by the bees, hummingbirds and butterflies. Mine grew to 15' tall and is very leggy as I never trimmed it to make it a shrub. Literature says it lasts about 15 years. It is very showy.. My beans I have on it now, look exactly like the Chinese green beans you see on Chinese buffets. Mine are green, maybe they turn brown later? It quit flowering about end of Oct or early November and was bright yellow, just full of flowers. Quite a showy plant!