black runner beans

hi someone on my allotment gave me some runner bean seeds a few weeks ago when the beans grow they are black but when you cook them they turn green, but for the life of me I cannot find them don't know where they have gone have turned the house upside down looking for them. does any one know the name of a runner bean of this description also he told me they are stringless . dont want to tell him I have lost them so trying to buy some so I can still grow them. have googled them but to no avail any one know out there
thanks

 

Blau Hide.

 

hi thanks for that have just found them after empting all the cupboards in the kitchen !!!

 

Now theres dedication

Remember not to plant them where a mouse can eat the seeds or you'll be back to square one.

 

Black Prince is another one... V useful, as they are easier to find on the plant, and even when cooked, they are a little brighter green than "normal" beans. We like our beans al dente, the purple-black ones are ready to take out of the steamer when they turn green.

 

I know I'm responding rather late to this post (just three years late!!) I've only just signed up to this forum.

I've bred a variety of purple podded runner beans called the AERON PURPLE STAR (Google it). It's taken nearly 15 years of painstaking breeding to get it right.

I give them away free to fellow amateur gardeners - check them out and compare them to the ones mentioned above.

 

Would you have a few I could slip in the seed swap parcel please, http://www.gardenerscorner.co.uk/forum/threads/seed-swap-2015.103701/