They are self pollinating, but they do well only in an English/northern Europe type climate. Maybe it is too hot in your greenhouse. They should produce outdoors in your climate.

I may be wrong but my understanding is that although runner bean pollen is self compatible they don't actually pollinate themselves. They need insects to do that for them. Can bees etc get into your green house? I agree with farmerdilla that they would be happier outside in BC. They like plenty of moisture, rich ground and temperatures such as we get in a UK summer eg around 60 - 80f. Also the first few flowers frequently fall withouth producing beans. So open the windows, put on some shading and be patient. You may well get beans yet.

You know, I remember having a similar discussion regarding runner bean pollination... but I can't seem to find it, nor can I find the reference I quoted then. As I recall, it was a U.K. government study, which stated that the construction of the runner bean flower made auto self-pollination impossible. An insect visit repositions the anthers with regard to the stigma, allowing pollination to occur. In my own experience, runner beans need both cool temperatures & pollinators to produce seed.

However, another U.K. GW member has blossom-bagged runner beans, and obtained seed from some varieties, but not others. The degree of self-pollination may be variety dependent.

I would agree with the others above; if you open your beans to the outside air (and pollinators) you should get seed. If this is not possible, you may have to manually "trip" the flowers to simulate an insect visit.

I am also having trouble with getting my runner beans to set. How do I 'trip' the flowers? I know how to polinate tomatoes with an electric tooth brush and squash with a q-tip but I've never done this with beans. I have some polinators in my small garden but maybe not enough, this variety is supposed to grow well here in the San Francisco Bay area? Any suggestions would be welcome, I'll try to keep them wetter since we don't seem to get any rain.

Thanks,

Kristi

I have had the door open for 1.5 weeks now, getting more pollinators in and a little cooler. My tomatoes, in the same green house, are getting pollinated, usually 3 or 4 tomatoes per 6 flower bunch, is this normal rates? Thank you for the advice will try to be a little more patient.

I was on the allotment today and the Painted Ladies are setting beans without problems. The weather has been 60 -70 and raining every couple of days. Perfect runner weather. I spoke to a neighbouring allotmenteer and she said she sprays her beans with sugar water to attract bees. Other growers say to spray with water. I have never found either necessary but you could give it a try. The idea of hand pollinating runner beans is not really practical. We're talking about many hundreds of flowers over a season. Kris, the problem may be that it is just too hot in CA.

Another point is that I do not know of anyone here who grows runners for eating as beans, only for the green pods. If you allow seed to ripen the supply of beans dries up. I only allow a few pods to ripen at the end of the season for next year's seed.

And finally ... this year at least half of last year's runner beans have reappeared having overwintered in the ground. Global warming? Or a thick layer of compost?

Thanks for the info flora. I looked again today and my latest set of flowers do have a few very tiny beans setting. I think maybe it did get too hot here, and I don't think I was watering enough. We typically have highs in the 70s and lows in the 50s this time of year but we had an unseasonal heat wave and that probably did in my last bloom of flowers. Now that temps are down I'll water more and hope for lots more flowers, it did seem like too many flowers for hand polinating but maybe I'll try the sugar water, it might attract more humming birds too (they are too cool).

As for overwintering, I read that they could do that in our area and the UK is even more perfect for them so I guess it just depends on how cold your winter is.

I am having the same problem with no pods being set. We have been having a mixture of hot and cool, wet weather in Ohio, so I am not convinced that is the problem.

All my other veggies and flowers, including beans, are all setting just fine.

Anyone know specifically what insects pollinate these buggers? I am wondering if there is a lack of pollinators.

Flora and Kris:

"As for overwintering, I read that they could do that in our area and the UK is even more perfect for them so I guess it just depends on how cold your winter is. "

This was one of my experiments last year. I cut my runner beans down and mulched heavily before the first frost. Ok it has been a colder winter than some, certainly down to -9 C on several occasions, but despite mulch a foot thick, not a single runnerbean re-emerged. Quite disappointing. I will revert to what I normally do, which is to dig the roots up, overwinter frost-free with a little soil and only very occasional watering, then replant the following year. This way I get a good percentage of plants regrow a second, even third year.

Zeedman,

I found it is easy to isolate and self pollinate runnerbeans of variey 'Painted Lady', variety 'Butler' on the other hand did not set any beans at all with blossom bags. All other varieties set some beans.

Aldernon

Bees, wasps and bumblebees are the main pollinators. They are heavy enough to open the flowers when they land on the keel. Of course this will also 'trip' the flowers to some extent.

Galina - I live in the South West and we didn't get much below freezing at all last winter. The pond had a thin skim of ice on 2 mornings I recall. I didn't intend to overwinter the runners. Just cut them down and composted as usual. I've never had so many come back before. Most are Painted Lady but there are also some unnamed red ones which I got from the greengrocer. Of my self saved seed most has this year produced Painted Lady flowers but there are a few plain scarlets too even though I selected only seed that looked like PL. Must have been some cross pollination.

Well, I'm picking up this subject realizing that the last entry was in 2008!

I come from England and have always had great success with scarlet runners there. Here in N California, that is not so!

For 2 years running, I have had hardly any pods forming, dammit! After much theorizing about the negative effects of high summer temp's here (E.g., ave. temp in July is around 93) - which I don't find convincing, as the original runner bean did I believe come from sub-tropical S America; and noting that all my other fruits and veg's are doing amazingly well in my deep and/or raised beds, including bush beans -

MY theory is: humming birds! We have many of thse beautiful but, as far as the runner beans go, PESKY critters in our yard, and I observe that they have a distinct preference for the scarlet, and scarlet & white, flowers. I think they're using their long tongues to take the nectar, which they don't enter the flowers to do - unlike the beneficial bees, who effect the cross-pollination by actually entering the flower and getting pollen on their bodies, transferring it to the next flower, and so on ... SO, when the humming bird's been a-calling, there's no nectar left for the bees, who seem to know that ... I see them hovering at the lip of the flower momentarily, then going on their busy/buzzy way!

Solution!?: I'm experimenting with netting, which has mesh just wide enough to admit bees, but not birds - even the diminutive humming ones! I know bees are getting through the mesh, because I put a couple of rows of bush beans between the rows of beansticks, and they are producing like Billy-O, as we say in Britain.

I'm now waiting to see if I get any pods forming on the runners ... five days, and no sign of any yet. Hmph! The other thing that's happening is that the bean-tendrils have started to climb through the mesh, so I now have protected bean flowers inside the mesh, and an increasing number of unprotected ones outside it, reaching for the sky!

Regardng all of the above, the best case scenario is: I will get lots of beans forming inside the mesh, and the beautiful humming birds will still get to nosh on runner bean nectar from the ones 'beyond the pale'!

Watch this space ...

Good luck with that. Will be interesting to see what happens.

I have grown IWK runners the last couple years, saw hummers visit them, and still got beans.

This year I'm growing Sunset runner, we are just coming off a heat wave, and all blossoms so far have aborted with no beans.

This was my first year growing Scarlett Runner Beans. I planted them in April. By lat may early June I had big vines with lots of flowers, but only the occasional bean. Now it's the end of July, and I'm harvesting beans everyday. Just took patience for me.

BTW, I'm in Northern California with temperatures in the 80s in the day and 60s at night. As for bees, there are lots of them all over the vines and hummingbirds too.

My Scarlet Runner Beans dropped almost every flower and made only 5 beans off 15 plants. I thought it was some kind of bug.

Kranberriz, I have found two things that prevent pods from forming. The blossoms drop until the bumble bees start to visit. They also drop when it is hot. The exact temperature varies with variety but in general around 90F may be the limit. - Dick

Yes...I can relate to all this.
My Scarlet Runners had a beautiful growth of foliage and the flowers were something to behold..Plenty of bees ..no problems there.Then the warmer weather arrived ...temps 34 to 38C... The flowers dropped and there was no fruit set worth mentioning...I think about 8 pods !!!
Painted Lady was quite different ...Good healthy growth and crop.
Wont replant Scarlet Runner given some space limitations
Regards to all....Geoff

Scarlet Runer beans need cool nights in hot climates. Its best therefore to plant them late summer so seeds will set. Spraying with cool water at dusk and keeping well watered also helps to create great conditions for them. Moving to a cooler cliamte certainly helsp as I always had success in cooler areas. More here https://www.youtube.com/watch?v=RL973BSIjOY