A Bean Muddle

A beautiful basket of beans, eh? But wait, they should all be the same. Clearly they differ.

A harvest of mixed pole beans.

When I planted this spring I thought I was planting Rattlesnake pole beans. Rattlesnake beans are green with burgundy markings, or sometimes all green. There are a few in the picture. What are the rest and where did they come from?

For the last two years I’ve been saving seed from my pole beans. In 2010 I grew Rattlesnake and a purple pole bean called Blue Coco. The trellises were 6′-10′ apart and I collected seed from both. I grew the seed in  2011 and didn’t notice any problems.

In 2011 I made of mistake of planting the Blue Coco beans on a trellis right next to the Rattlesnake beans.  I thought beans were largely self pollinating. Clearly I was wrong.  Blue Coco crossed with Rattlesnake, resulting in greenish purple beans that are not anywhere as intensely purple as the original Blue Coco.

All the seed planted in 2012 was from Rattlesnake mother plants. I could tell by the seed coats which were brown with black markings, the color of Rattlesnake beans seeds. However the pollen which fathered many of the seeds must have been from the Blue Coco beans. By the way, Blue Coco seed is a plain beige, which darkens over time.

Blue Coco characteristics seem to dominate in this Rattlesnake x Blue Coco hybrid. In color, time of peak harvest, and flavor, these purple beans are more like Blue Coco than Rattlesnake beans.

Unfortunately for me, it’s Rattlesnake that I prefer. I’m going to buy seed next year to get back to the pure strain.