The Runners have been a bit slow off the mark this year. Lots of the early flowers did not set.
Many of the flower-stalks look like this - just the odd one or two pods, and lots of empty stalks:
A few of them are completely bare:
Opinions about the cause of this vary a lot. Some people blame a scarcity of bees to pollinate the flowers; others believe that hot dry weather and insufficient moisture in the soil is the cause. I don't know, but the effect is clear - I have had a lot less beans than I would have liked (and expected). Insufficient moisture is unlikely to be the cause in my case, because I have been very careful to ensure the soil in the bean-bed is kept adequately watered.
The pods I have harvested so far are mostly "Streamline" ones. Up till now the "Tenderstar" plants have only produced about 3 pods big enough to pick.
Even the "Streamline" pods are not exactly prize specimens. They are mostly somewhere between six and eight inches long, which is not so special for Runners. It's not as if I'm picking them too young either - as you can see in the photo below they are definitely mature - you can clearly see the beans inside the pods.
Many of the "Tenderstar" pods are short and curved, instead of being long and straight:
I often get a few pods like this at the end of the season, but not in the height of Summer! Does anyone have an explanation of why my beans are like this?
I'm hopeful that the situation may improve a bit in the not-too-distant future, because we have had some rain now and the beans can certainly not justifiably complain about being hot and dry - the temperature has been about 18 or 19 max! Furthermore, I have lots more flowers opening on other plants too, and the visit-rate for bees, particularly honey-bees, has gone up dramatically. Having said that, it's mostly Bumble Bees that pollinate beans, isn't it...?
Lack of beans is definitely pollination. Curly beans are often thought to be caused by temperature changes.ReplyDelete
Having said definitely pollination, the RHS https://www.rhs.org.uk/advice/profile?pid=381 suggests a few things. Again westher can play a part as well as soil.ReplyDelete
I have seen courgettes, cucumbers and tomatoes have pollination problems this year. Plenty of bees but the bees are swarming over my comfrey and aren't going much further. My bee keeping friend tells me that often we can plant bee friendly plants that are just too attractive to bees. He suggested moving comfrey to near other plants that needed pollination and moving these plants to more sheltered areas. Wind will stop bees visiting plants and they will stay near their preferred plants which may be more sheltered.
Thanks, Andy. Useful input.Delete
I was interested to read the comments under your post, Mark, as I have absolutely no answers for you. Sorry. I do know that the slow summer we've had has affected many plants and I think that climate change is well and truly with us - time to throw the rule book out of the window! The RHS site also says that hot weather can inhibit pollination grains thus causing pods not to set; once the weather cools (oooh, that will be this week then) cropping should continue. It's a very confusing summer for us growers!ReplyDelete
Our beans are just starting to flower so I can't comment in how well the beans have set. We have plenty of bees and have had far better summers when beans have set just fine. I know some people spray the flowers lightly with water to get the pollen flowing.ReplyDelete
Our runners have also been very slow this year, I managed to pick just a handful for our local agricultural show yesterday, fortunately they were for my basket of veg, not to show as runner beans.ReplyDelete
My runners are pale sickly plants. Lots of flowers, nary a pod. They are in a bit of a wind tunnel though so maybe that's the problem.ReplyDelete
I was always under the impression that curly beans were due to sporadic watering but this is obviously not the case with yours. The only other thing that springs to mind is disease or blackfly damage. Mine are suffering dreadfully from blackfly this year.ReplyDelete
Some varieties are less adaptable to hotter temps and your runner beans may be one of them. I've had a "bean gap" in the past during the heat of summer, so I can certainly attest that this does happen. Once the weather cooled down, the bean train was back on track.ReplyDelete