runner bean problem

[carpman]

Could anyone tell me why my allotment neighbours runner beans all turn purple when the get a reasonable size. He saves the seed from year to year so he doesnt know how old they are. The variety is Enorma.

The beans on my allotment are fine green and tender and quite long but these were raised from fresh seed.

[paulsherwin]

Do you mean the pods, or the beans inside the pods? It's normal for the beans to change colour like this as they mature. In my experience runner beans can't be harvested in the traditional manner (i.e. to eat the pod containing the beans) when they get to this stage as the pods will be too stringy. You can still eat the individual beans though, just like broad beans.

Paul

[spes123]

I must admit that I have not seen the pods turn purple, a yellow brown colour yes but purple no. However I have seen the beans inside turn purple as they mature and have used these to save as seeds for next year.

[carpman]

Thanks for your replies. In this case it is the pods themselves which have turned a dark purple. the seeds inside seem normal and ready for collecting.

3 seperate rows of these beans have been planted on the allotment in different areas at different times and all have turned a dark purple. I will try and get a photo to post on the site

[DavidT]

As these seeds have been kept year on year, I am wondering if they have been cross pollinated with a purple variety.