If I could only watch one gardening channel it would be this one. Wow- you get straight into it and each presentation is such a through and excellent essay! So organized and easy to listen to and understand while keeping attention. Your observations are so relevant and valuable. No showing off or egoism- just intelligent and curious observations and experiments of a true gardener and naturalist. You are deeply appreciated. I could relate to everything you said as I am watching my scarlet runner beans this year. I’ve barely seen a bee on the flowers at all yet the comfrey adjacent to the beans is buzzing! Not many beans so far, none on the first 5 flower stalks of any plant- it is up against an east facing wall that gets quite hot before the sun moves off at noon. Thank you for your wonderful work! 🙏🏻
I had the same problem and I spoke to a specialist and he told me that because of the heat, the pollen dries up and the flowers are no longer pollinated. another cause would be the lack of water... the plant grew big and its needs changed and another cause would be the cold water with which the plants are watered, in contrast to the heat from the poly tunnel
I hadn't really considered the heat ebbing too much for the pollen, which is definitely a possibility, though I have experienced the same issue with the plants outside which would not be exposed to anywhere near that heat (being in Ireland!). I think lack of water is a key factor, but as with many things it is likely a few different things coming together, or the same result (aborted flowers) from a range of different 'stresses'.
Thank you for taking such a scientific approach to trying to get the runner beans to produce more pods, and sharing it with all of us. This type of information is so helpful. While it may not be a 'controlled study', it provides valuable information for the average grower.
great video brother!... IMHO it has a lot to do with the uprooting of the root system and then transplanting it... normally the plant would have a nice established set of roots from which to draw upon during its second year of growth so possibly didn't focus as much energy into establishing a whole new root system that second year and so could not support such a massive production of pods... plus like you said I think a plant just gets to a point where it feels its purpose has been achieved in this life and stops producing!
I love your deep analysis! My gut feeling is that you needed to do periodic deep watering and adding more sand and worm casings to your soil so the beneficial mycelium can spread better. We've come to be terrified of overwatering! Rightly so often but sometimes we overcorrect... Poor plants😔
In Italy they say that beans require misting the flowers every evening to cool down the flowers and promote pollination. The variety I plant doesn’t make as many flowers as yours, only 2-4 per trellis, and they stop growing as soon as I forget to harvest for a couple of days
I had the exact same problem as this. The plant flourished with lots of flowers and bamboo bees visiting them but I didn't see pods forming until much later. There weren't many beans to be picked. I pulled the plant out about mid July.
Sounds like your plants put a lot of energy in growing fast especially with a strong root system, in my experience you need to feed every month if you are using organic fertiliser or compost. As they run out of nutrients, and grow outside. I have 5 plants that have never been moved in 5 years and never fail to produce a lot of beans.
I think it might be spider mites, they love it dry and the runner beans in the tunnel are drier and that might give them an opportunity to establish. Spider mites grow on those little black nightshades in the undergrowth. I grew great runner beans in Ireland most years with little effort. I emigrated to Victoria Canada about 20 years ago. It's much harder here. Even though its way warmer, its also way too dry in summer. I start them inside or in the greenhouse and plant them out when the vines are 4 or 5 ft tall (above the slugs). Usually I get beans before Canada day, July first and keep getting lots of them till late september or early october then they tail right off and I harvest the last of them in early november. It's vital to keep them well watered and pick them every 3 or 4 days. I don't think you can pick a "truss" in one go. You got to pick off the long ones and then the others will grow. I often get spider mite issues in august. They are bad! You can't see them but the tell tale web is there and you might see bigger predatory mites or tiny grubs that eat the spider mites. I sometimes have to tear off lots of lower leaves and and sometimes the plants produce second growth and recover. I have to keep them watered continuously. I have a "bean boat" (a rock planter shaped like a boat) that has a "hold" under it and I pump water up all day ( airlift pump and boar scare to distribute the water) (I call it "soiloponics") and I get good results with it. But growing them in the ground would cost me an arm and a leg because water here isn't cheap.
Thanks for the video. Always interesting topics and plenty of idea or thoughts to solve the issues. Looking forward to seeing how my runners/pole beans produce. Garden is much slower this year with the cooler weather. Thanks again
I've seen the same thing. I suspect there is some sort of hormonal limit that cuts off pod development triggered by signals from the maturing seeds. It's just a guess, but perhaps that's why a steady harvest allows greater overall production. I grow most of my beans for drying, and see the same limits regardless of how many flowers grow. Leaving just a few pods on the plant for dry seed doesn't seem to be enough to trigger the, "woah, I better slow down," signal, though, if I harvest continuously. It might be interesting to do some experimenting to see at what physiological level those hormonal signals function; is it just per truss, or per stem, or the entire plant? It seems like half a dozen plants or so would be enough to run the experiment.
First time I have grown runner beans this year, grew them from seed and planted the plants into 3 x 30 litre containers , 6 plants per container in peat free compost. Sown 03/05, planted out 24/05. The plants grew very vigorously and soon reached the top of the 6ft bamboo canes. However there have been very few flowers and those which have formed have either dropped off or have been eaten ? By birds, thus loads of greenery but very few beans. The containers have been watered regularly and each container mulched to help keep in the moisture. Don’t know reason few flowers, loads of bees etc as garden is mainly planted with flowers. My containers of Charlotte potatoes have done fairl well though.
Depending on the size of tub, maybe too many plants? I planted 4 beans in 49cm square tubs, one plant per cane. They did ok. Try banana tea to encourage flowering.
I'm trying to raise them in Arizona. Not much luck because of temperature swings from the 40s to upper 90s. They do best in fall when nighttime temps are lower and sinking. A heavy frost ends the tops, but many come back in spring when surges in heat kill them.
One thing to always consider when comparing inside a poly tunnel vs outside is the light difference. The plastic is going to filter out some of your light, changing the color spectrum and the amount of light that your plants get, and the human eye is really bad at picking up on this. It's possible that the plants think they are in partial shade, or are getting less light than they need.
I have no idea but maybe the plants have a limit of beans they can efficiently produce? Maybe after so many pods the plants stop producing viable flowers?
I am guessing that this large number of flowers might be a "safety mechanism" that evolved in beans in case something happened to the first developing beans. For example if there were only 5 flowers, a heat wave or a herbivore at the wrong time would completely prevent the plant to reproduce. So having extra flowers ensures that the plant can produce its 5 or so pods per truss. And any extra fertilised flower is just avorted
I agree with your analysis, and you've got quite good data here. I think the simplest answer is that the beans simply don't waste resources producing more beans on a truss once a certain number has been set. This is consistent with your observation that the first flowers on the truss set then the rest die away then fail to form.
My opinion is that a single plant can produce that much. I have to say that with beans I achieved the most various results, from total failure to unexpected success, with no clear cause/effect motivation.
I had no idea beans were actually perennial plants, that is so weird. When I first heard it about chilli plants, I wasn't surprised as it honestly made sense, but hearing the same thing about beans really shocked me.
God bless you sir for the gift of your experience. So I can winter my grandchild rb plant that failed, no 🐝 or 🦋 this year 😢 but at least I know I can winter it and try again next year 🥰
How was the HEAT index when they stopped growing? I've noticed, here in TN, our beans seem to stop during the hottest part of the summer, but as soon as it started cooling off again, they started growing again. They were "Scarlet Runners."
@@REDGardens When growing at Diss Community Farm, in Suffolk, this was our experience too. Peak heat led to a pause in flower and pod development, but when there was less heat stress development resumed. Unravelling your observations could it be the common varieties overproduce when the early summer growth is strong, but need to pause when highly loaded with developing pods and then hit with a stress condition? Clear the overload and remove the stress and development starts again. It does not appear to be a nutrition problem.
I under-watered my broad beans and had the same thing happen last week, the plants started aborting younger pods. So my hunch would be a weakened root system from transplanting, combined with a lack of water. Maybe the high number of pods is also due to the stress of transplanting + not enough water? Plants can set a lot of seed when they struggle and feel that their chances of reproduction are getting slim. Maybe that's the case here?
Well this year I’ve had total failure🥺All my runners have failed to set. RHS says too dry at roots Evidently pollen can’t form. It’s a new bed and in the full south of the house wall. Now the first rain has arrived it’ll be interesting to see if they pod . Plenty of leaves and flowers but the bees flit and fail to find anything. 😕
Runner beans need cooler weather or they don't produce. In the south of the us they won't produce most summers. I think Europe's hot dry weather favours french climbing beans this year. My runner beans from seeds haven't produced yet either. I'm curious if it's will stay too hot if I get any beans at all
what a fascinating thing, and not something I had really thought about. It isn't as if the plants didn't look healthy either. They looked as lush as any other runner bean plants, and the roots looked strong. If they weren't then they wouldn't have grown such amazing plants. Great idea btw - lifting the roots and storing them! I guess it must be as you say that the plants have happily produced enough for them to have reproduced, and it was quite enough for the plant to cope with. I wonder how they will perform in a third year? Will you give it a go to see? Maybe a few inside and a few out?
@@REDGardens That's great, I really look forward to seeing how they compare - like new and older plants. I wonder how the amount of harvest will differ too, if at all.
plants know what season it is despite being in an isolated environment... I can't fully explain it, but I've noticed this with plants grown indoors with artificial lighting. maybe it's a combination of the humidity and average temps, or the moon? idk... I haven't been able to pin down a specific cause. lack of evaporation and overly cool damn soil is a leading theory though. having dug up the plants and moved them would have also reduced the overall root mass and opened up potential for root rot issues in those soil conditions so maybe that's it.
Hi Bruce this was a fascinating video, I've never grown runner beans before but they seem like fascinating plants! Maybe they don't like more than a few beans on each truss and by hand pollination making them produce more than they like made them give up? But what the hell do I know!😁
It is interesting that the beans stopped forming or failed right around the summer solstice. Have you noticed any changes on the outside beans at the same time? I am wondering if the poly tunnel had an impact on light requirements not observed outside. In Ireland, is there a way to protect the plant from freezing without digging it up? I grow perennial Jack beans and notice that additional pods will not form if a mature pod is on the spray. When I pick the beans while tender, additional pods will grow on the same spray.
Cucumbers, courgettes and other fruiting plants are the same for me. No matter how many flowers get pollinated, there will be a set amount of fruits on each plant depending on the size of the plant. They will grow new ones if I harvest the old ones.
I wonder if the plant adapted to being outside and the change of location was shocking in some way? I'd like to see some new plants that pass all of their years in the tunnel to compare with the transplanted one, for comparison.
Wine growers say that it takes 16 leaves to ripen a cluster of grapes. I suspect your plants are just keeping the number of beans proportionate to the size of the vines and their ability to supply the growing beans with nutrients.
That is very interesting about the grapes! I suspect you are right. The thing that interests me is why the plant would produce so many flowers in the first place. And why does all of the advice about runner beans not mention this?
@@REDGardens I have a theory based on what you mentioned in the video. Maybe so many flowers form on each cluster so that if a long lasting heatwave comes, meaning no pollen for a week or two, there are still flowers left on each cluster which can be pollinated and form the maximum amount of pods the plant can handle.
@@Pepso8P I was thinking along those lines. The overproduction of flowers acts as insurance against poor conditions during pollination. Apples do a similar, though not exactly the same thing: if the king bloom is pollinated then the other flowers in the cluster drop off. If the king bloom fails then all the other flowers in the cluster will form fruit if pollinated.
i'm wondering the experiment that 3/4 of the flower stems will be cut off before they will blossom. Reducing possible number of the pods. In this scenario remaining flowers should produce more pods on one stem. This approach work perfectly on wine bunches where wine produce a lot more flowers than plant can support. If this approach will be successful it will proof that plant dropping pods because it can not provide enough nutrients to support them all. If also could help reduce harvesting time simply by remoting flowers that will produce pods in hard to reach places.
Maybe you could halve the flower trusses on one of the plants next year, and see if that results in more pods per truss. It's a common strategy for fruit trees, as you undoubtedly know.
I'm curious... If you put 1st year beans along side the over-wintered beans in your polytunnel, do the first year beans show the same behavior? If so, that might narrow it down to an environmental factor.
I have also tried runner beans in my polytunnel with similar problems in the UK, first flowering followed by small pods but no further development, there are no bees or pollinating insects in the tunnel and so this year I have researched the problem and selecting self pollinating varieties and will give them a try. Have you considered this possibility?
That is interesting, and might explain part of the issue I saw in the polytunnel, but not in the outside gardens as we never get that temperature here in Ireland.
You have to pick them. It’s like sweet peas, if you don’t pick them they stop flowering, once they have full sized beans on them they automatically stop. My grandfather would pick ALL the lower beans.
What about light? I know many plants use the sun's wave length to decide if it should produce seeds. If it's something that always happens at a certain time of year, this could be very likey. Do they start to produce pods again, as the sun's wavelength changes again? Spring/Fall vs Summer
Try to thin out some of the flowers on a few plants to see if you get more beans produced . This might put more energy into production of beans then flowers.
Same issue in northern Minnesota. Thanks for your interesting insights. I became convinced that leaf hoppers were damaging the flowers. Is that possible?
I have not seen a single bumble bee on my runner beans in the uk yet. I have just two pods developing on large healthy looking plants. This year it seems like lack of pollination is the main problem for me.
If I had to bet, I would put my money on not enough water. I'm pretty sure I've had that exact problem and it seems to follow the same pattern. A few years ago I just forgot to water and the beans, which had started to develop, just "dropped" off the vine.
Sounds like it may be a nutrient deficiency to me. Access to certain minerals may be limiting the plants’ ability to properly build their reproductive organs, in the quantities that they initially estimated during vegetative stage. If your soil is drying out and only has moisture in certain areas, then I would expect that this will certainly restrict soil life and the available area for the plant to exchange its exudates for nutrients. John Kempf talks about ‘critical points of influence’ as stages during plant development that you might find interesting and relevant
I suspect something 'simple' to do with gravity. As soon as there are 5-6 pods, moisture (water, growth hormone transport?) first sinks down into the already existing pods meaning less 'stuff' goes to further down the end of the branch which leads to a deficiency that 'aborts' already existing / formed pods, or stops the succesful fertile production of male/female parts of the flower. Nature usually doesn't "think" too deep, we need to look for the solution close to the laws that govern plant growth. How knows. Keep experimenting!
Here in Sweden we grow this variety of runner beans exclusively for the flowers and many are not even aware the pods are edible so why not try another variety of beans?? I’ve grown these fore many year’s and noticed the same as you; a rather short productive period and I’ve accepted it as is ;)
That is interesting. I generally accept whatever is produced by these types of plants, but in this case I was hoping to see how much more could be produced.
judging by the size of the bean pod with almost full sized bean in side ...to me your not picking fast enough and early enough. .must pick every day before seeds start to develop if you want tender pods to eat there are always one or 2 that get missed ether because it is deformed you can't leave it to seed that will stop production.
My suggestion would be a nutritional deficiency, not a N, P or K but a trace element. This is easy to test, add a small amount of rock dust to the compost in one section and do a side by side trial and if it is a deficiency then you will see a sharp drop as you move away from the amended area.
You might be doing everything right, and still not getting full trusses of beans is the optimal performance from the plants POV. My intuition is that plants produce more flowers than fruit as a survival strategy. Plants that produce both male and female flowers skew heavily on male flowers because it requires less resources to *maybe* pass on genes while not spending a lot of resources on a fruit. For a plant that has perfect flowers, producing some flowers that produce some pollen but maybe do not produce the fruit and it is aborted might be slightly more adaptive than producing the exact amount of flowers for exact amount of fruit they can produce given their resources. Their resources being leaf area for carbs, but also water and mineral uptake by roots. Anyway, extra flowers might mean extra pollen from non-fruiting flowers gets spread about that might turn into seed on other plants, which genes spread to more offspring. And this might not be a bad thing for us. Ultimately we care about mass per square area or calories per square area. Though, it's complicated. Mass includes water weight, which varies. Calories do not take into account other nutrients, like vitamins and minerals. Mass per area won't take into account vitamins and minerals either, but mass fills your belly. Pick your poison, right? If you are comparing apples to apples, and the calories/nutrients are roughly the same between the same species/varieties, which every plants produce the most mass/area are the ones you want to favor, and not worry about pods per truss. You can ignore the aborted fruit and just measure the finished fruit.
Ah, now I wonder if the genetic origen of the seed has something to do with that. You may have forgotten that in these Islands Runner bean plants were not planted or bred for the beans. They were planted and tended for their flowers. They originated in Mexico and were brought to Europe as flowers. Like sweet peas which are genetically peas but bred for a very long time for their flowers they have stunted pea pods. I'm wondering if the flowering genetics outweigh the seed genetics when it comes to these plants and maybe as you collect your own seed, after a few seasons that could be a factor in your observations. Just wondering, that's all.
I'm not well versed in the native plants in your area. But I'm wondering if there aren't any native wild bean plants in your area there could be a lack of nitrogen fixing bacteria in the soil for the beans to pair up with. I know in some cases people will inoculate their beans with the correct bacteria before planting them.
That is an interesting point. I do remember finding some nitrogen fixing nodules on these plants, but perhaps more would help. When I first started growing in this area, I noticed that there were no nodules on the peas and beans I was growing, probably because this field had only been growing grass for decades. So I brought a bit of soil from my old garden where `I had grown peas the had produced lots of nodules, and added it into he rows when sowing the peas. It worked, and I think it owed probably be a good thing to do every time I sow beans and peas.
I had heard that, and also read that it can also prevent pollination. In this case there was full pollination then suddenely nothing on any of the trusses and nothing changed as far as I am aware.
I'm no expert but I saw another You Tuber say that you should harvest beans when they are younger so that the plant does not think "I've made my seeds so now I'm done." You seemed to be harvesting very large beans.
Have you measured the CO2 in your poly tunnel? CO2 is a plant food. Most commercial growers increase CO2 to about 800 ppm in greenhouses. Outdoor CO2 has limits and thereby limits plant growth. Plants can grow only as well as the least available nutrient. Hope you figure out your mystery!
If I could only watch one gardening channel it would be this one. Wow- you get straight into it and each presentation is such a through and excellent essay! So organized and easy to listen to and understand while keeping attention. Your observations are so relevant and valuable. No showing off or egoism- just intelligent and curious observations and experiments of a true gardener and naturalist. You are deeply appreciated. I could relate to everything you said as I am watching my scarlet runner beans this year. I’ve barely seen a bee on the flowers at all yet the comfrey adjacent to the beans is buzzing! Not many beans so far, none on the first 5 flower stalks of any plant- it is up against an east facing wall that gets quite hot before the sun moves off at noon.
Thank you for your wonderful work! 🙏🏻
the bees are so cute
It is great watching them work over all the flowers.
I had the same problem and I spoke to a specialist and he told me that because of the heat, the pollen dries up and the flowers are no longer pollinated. another cause would be the lack of water... the plant grew big and its needs changed and another cause would be the cold water with which the plants are watered, in contrast to the heat from the poly tunnel
I hadn't really considered the heat ebbing too much for the pollen, which is definitely a possibility, though I have experienced the same issue with the plants outside which would not be exposed to anywhere near that heat (being in Ireland!). I think lack of water is a key factor, but as with many things it is likely a few different things coming together, or the same result (aborted flowers) from a range of different 'stresses'.
Thank you a very interesting presentation
Gosh those flowers are so beautiful
beansgrow from 4am to 12pm midday, after this they stop growing... A south-facing aspect is a positive position for this. :)
This was extremely helpful, thanks so much.
Waiting patiently for a new video 🥺
You could say they were tired of running.
Thanks so much for sharing Bruce!
Thank you for taking such a scientific approach to trying to get the runner beans to produce more pods, and sharing it with all of us. This type of information is so helpful. While it may not be a 'controlled study', it provides valuable information for the average grower.
great video brother!... IMHO it has a lot to do with the uprooting of the root system and then transplanting it... normally the plant would have a nice established set of roots from which to draw upon during its second year of growth so possibly didn't focus as much energy into establishing a whole new root system that second year and so could not support such a massive production of pods... plus like you said I think a plant just gets to a point where it feels its purpose has been achieved in this life and stops producing!
Thanks! I think that is a big part of it.
Well said, Nate. Nice to see you here. I just watched your fertilizer video. 👍
I love your deep analysis! My gut feeling is that you needed to do periodic deep watering and adding more sand and worm casings to your soil so the beneficial mycelium can spread better. We've come to be terrified of overwatering! Rightly so often but sometimes we overcorrect... Poor plants😔
How very very interesting and intruiging! Thanks for sharing this :)
Fascinating!
Love your videos, thanks for the always useful information!
Thanks!
In Italy they say that beans require misting the flowers every evening to cool down the flowers and promote pollination. The variety I plant doesn’t make as many flowers as yours, only 2-4 per trellis, and they stop growing as soon as I forget to harvest for a couple of days
I had the exact same problem as this. The plant flourished with lots of flowers and bamboo bees visiting them but I didn't see pods forming until much later. There weren't many beans to be picked. I pulled the plant out about mid July.
I've never grown runner beans before this year, so thanks for the heads-up. I'll keep an eye out for this behavior.
Sounds like your plants put a lot of energy in growing fast especially with a strong root system, in my experience you need to feed every month if you are using organic fertiliser or compost. As they run out of nutrients, and grow outside. I have 5 plants that have never been moved in 5 years and never fail to produce a lot of beans.
I think it might be spider mites, they love it dry and the runner beans in the tunnel are drier and that might give them an opportunity to establish. Spider mites grow on those little black nightshades in the undergrowth. I grew great runner beans in Ireland most years with little effort. I emigrated to Victoria Canada about 20 years ago. It's much harder here. Even though its way warmer, its also way too dry in summer. I start them inside or in the greenhouse and plant them out when the vines are 4 or 5 ft tall (above the slugs). Usually I get beans before Canada day, July first and keep getting lots of them till late september or early october then they tail right off and I harvest the last of them in early november. It's vital to keep them well watered and pick them every 3 or 4 days. I don't think you can pick a "truss" in one go. You got to pick off the long ones and then the others will grow. I often get spider mite issues in august. They are bad! You can't see them but the tell tale web is there and you might see bigger predatory mites or tiny grubs that eat the spider mites. I sometimes have to tear off lots of lower leaves and and sometimes the plants produce second growth and recover. I have to keep them watered continuously. I have a "bean boat" (a rock planter shaped like a boat) that has a "hold" under it and I pump water up all day ( airlift pump and boar scare to distribute the water) (I call it "soiloponics") and I get good results with it. But growing them in the ground would cost me an arm and a leg because water here isn't cheap.
I haven't seen any spider mites, but something to look out for.
Thanks for the video. Always interesting topics and plenty of idea or thoughts to solve the issues.
Looking forward to seeing how my runners/pole beans produce. Garden is much slower this year with the cooler weather. Thanks again
I've seen the same thing. I suspect there is some sort of hormonal limit that cuts off pod development triggered by signals from the maturing seeds. It's just a guess, but perhaps that's why a steady harvest allows greater overall production. I grow most of my beans for drying, and see the same limits regardless of how many flowers grow. Leaving just a few pods on the plant for dry seed doesn't seem to be enough to trigger the, "woah, I better slow down," signal, though, if I harvest continuously. It might be interesting to do some experimenting to see at what physiological level those hormonal signals function; is it just per truss, or per stem, or the entire plant? It seems like half a dozen plants or so would be enough to run the experiment.
First time I have grown runner beans this year, grew them from seed and planted the plants into 3 x 30 litre containers , 6 plants per container in peat free compost. Sown 03/05, planted out 24/05. The plants grew very vigorously and soon reached the top of the 6ft bamboo canes. However there have been very few flowers and those which have formed have either dropped off or have been eaten ? By birds, thus loads of greenery but very few beans. The containers have been watered regularly and each container mulched to help keep in the moisture. Don’t know reason few flowers, loads of bees etc as garden is mainly planted with flowers. My containers of Charlotte potatoes have done fairl well though.
Depending on the size of tub, maybe too many plants? I planted 4 beans in 49cm square tubs, one plant per cane. They did ok. Try banana tea to encourage flowering.
I'm trying to raise them in Arizona. Not much luck because of temperature swings from the 40s to upper 90s. They do best in fall when nighttime temps are lower and sinking. A heavy frost ends the tops, but many come back in spring when surges in heat kill them.
One thing to always consider when comparing inside a poly tunnel vs outside is the light difference. The plastic is going to filter out some of your light, changing the color spectrum and the amount of light that your plants get, and the human eye is really bad at picking up on this. It's possible that the plants think they are in partial shade, or are getting less light than they need.
That is possibly a factor, though the plants outside also behave the same way.
I have no idea but maybe the plants have a limit of beans they can efficiently produce? Maybe after so many pods the plants stop producing viable flowers?
I am guessing that this large number of flowers might be a "safety mechanism" that evolved in beans in case something happened to the first developing beans.
For example if there were only 5 flowers, a heat wave or a herbivore at the wrong time would completely prevent the plant to reproduce.
So having extra flowers ensures that the plant can produce its 5 or so pods per truss. And any extra fertilised flower is just avorted
Might be twaddle, but I've heard that runner beans need watered over the foliage to have better flower to bean rate
I agree with your analysis, and you've got quite good data here. I think the simplest answer is that the beans simply don't waste resources producing more beans on a truss once a certain number has been set.
This is consistent with your observation that the first flowers on the truss set then the rest die away then fail to form.
My opinion is that a single plant can produce that much. I have to say that with beans I achieved the most various results, from total failure to unexpected success, with no clear cause/effect motivation.
I had no idea beans were actually perennial plants, that is so weird. When I first heard it about chilli plants, I wasn't surprised as it honestly made sense, but hearing the same thing about beans really shocked me.
Not all beans are perennial, but these specific ones are.
@@Ultrazaubererger Yes, I think it might only be the runner beans that are perennial, at least with the range of beans I know about.
Also shocked me
God bless you sir for the gift of your experience. So I can winter my grandchild rb plant that failed, no 🐝 or 🦋 this year 😢 but at least I know I can winter it and try again next year 🥰
Very cool study on this plant. I have grown it a bit. I sometimes cut off the tip of the truss the way I would a tomato. 4-6 pods per truss.
How was the HEAT index when they stopped growing? I've noticed, here in TN, our beans seem to stop during the hottest part of the summer, but as soon as it started cooling off again, they started growing again. They were "Scarlet Runners."
It was still quite cool here in June, so not sure if that can be an issue.
@@REDGardens When growing at Diss Community Farm, in Suffolk, this was our experience too. Peak heat led to a pause in flower and pod development, but when there was less heat stress development resumed. Unravelling your observations could it be the common varieties overproduce when the early summer growth is strong, but need to pause when highly loaded with developing pods and then hit with a stress condition? Clear the overload and remove the stress and development starts again. It does not appear to be a nutrition problem.
@@REDGardens OK. LOVE your posts BTW!
I under-watered my broad beans and had the same thing happen last week, the plants started aborting younger pods. So my hunch would be a weakened root system from transplanting, combined with a lack of water.
Maybe the high number of pods is also due to the stress of transplanting + not enough water? Plants can set a lot of seed when they struggle and feel that their chances of reproduction are getting slim. Maybe that's the case here?
Love the videos! You are a huge inspiration.
Awesome! Thanks.
Well this year I’ve had total failure🥺All my runners have failed to set. RHS says too dry at roots Evidently pollen can’t form. It’s a new bed and in the full south of the house wall. Now the first rain has arrived it’ll be interesting to see if they pod . Plenty of leaves and flowers but the bees flit and fail to find anything. 😕
Runner beans need cooler weather or they don't produce. In the south of the us they won't produce most summers. I think Europe's hot dry weather favours french climbing beans this year. My runner beans from seeds haven't produced yet either. I'm curious if it's will stay too hot if I get any beans at all
what a fascinating thing, and not something I had really thought about. It isn't as if the plants didn't look healthy either. They looked as lush as any other runner bean plants, and the roots looked strong. If they weren't then they wouldn't have grown such amazing plants. Great idea btw - lifting the roots and storing them! I guess it must be as you say that the plants have happily produced enough for them to have reproduced, and it was quite enough for the plant to cope with. I wonder how they will perform in a third year? Will you give it a go to see? Maybe a few inside and a few out?
I plan to grow these for the third year, but now am also thinking of direct sowing another few beside them to see how a direct sown plant compares.
@@REDGardens That's great, I really look forward to seeing how they compare - like new and older plants. I wonder how the amount of harvest will differ too, if at all.
plants know what season it is despite being in an isolated environment...
I can't fully explain it, but I've noticed this with plants grown indoors with artificial lighting.
maybe it's a combination of the humidity and average temps, or the moon? idk... I haven't been able to pin down a specific cause.
lack of evaporation and overly cool damn soil is a leading theory though. having dug up the plants and moved them would have also reduced the overall root mass and opened up potential for root rot issues in those soil conditions so maybe that's it.
That is interesting, something to think about.
Hi Bruce this was a fascinating video, I've never grown runner beans before but they seem like fascinating plants! Maybe they don't like more than a few beans on each truss and by hand pollination making them produce more than they like made them give up? But what the hell do I know!😁
Thanks. That makes sense, but then I wonder why they produce so many flowers, like 20-30 on a truss?
It is interesting that the beans stopped forming or failed right around the summer solstice. Have you noticed any changes on the outside beans at the same time? I am wondering if the poly tunnel had an impact on light requirements not observed outside. In Ireland, is there a way to protect the plant from freezing without digging it up? I grow perennial Jack beans and notice that additional pods will not form if a mature pod is on the spray. When I pick the beans while tender, additional pods will grow on the same spray.
Очень интересно вас смотреть, не знаю английского языка, ничего не понимаю, просто смотрю.
Cucumbers, courgettes and other fruiting plants are the same for me.
No matter how many flowers get pollinated, there will be a set amount of fruits on each plant depending on the size of the plant.
They will grow new ones if I harvest the old ones.
There seems to be a limiting factor for some plants.
I wonder if the plant adapted to being outside and the change of location was shocking in some way? I'd like to see some new plants that pass all of their years in the tunnel to compare with the transplanted one, for comparison.
Wine growers say that it takes 16 leaves to ripen a cluster of grapes. I suspect your plants are just keeping the number of beans proportionate to the size of the vines and their ability to supply the growing beans with nutrients.
That is very interesting about the grapes! I suspect you are right. The thing that interests me is why the plant would produce so many flowers in the first place. And why does all of the advice about runner beans not mention this?
@@REDGardens I have a theory based on what you mentioned in the video. Maybe so many flowers form on each cluster so that if a long lasting heatwave comes, meaning no pollen for a week or two, there are still flowers left on each cluster which can be pollinated and form the maximum amount of pods the plant can handle.
@@Pepso8P That would make sense. Or if there was a drought then rained again, the plants cold adapt.
@@Pepso8P I was thinking along those lines. The overproduction of flowers acts as insurance against poor conditions during pollination. Apples do a similar, though not exactly the same thing: if the king bloom is pollinated then the other flowers in the cluster drop off. If the king bloom fails then all the other flowers in the cluster will form fruit if pollinated.
i'm wondering the experiment that 3/4 of the flower stems will be cut off before they will blossom. Reducing possible number of the pods. In this scenario remaining flowers should produce more pods on one stem. This approach work perfectly on wine bunches where wine produce a lot more flowers than plant can support. If this approach will be successful it will proof that plant dropping pods because it can not provide enough nutrients to support them all. If also could help reduce harvesting time simply by remoting flowers that will produce pods in hard to reach places.
Maybe you could halve the flower trusses on one of the plants next year, and see if that results in more pods per truss. It's a common strategy for fruit trees, as you undoubtedly know.
I'm curious...
If you put 1st year beans along side the over-wintered beans in your polytunnel, do the first year beans show the same behavior? If so, that might narrow it down to an environmental factor.
I have also tried runner beans in my polytunnel with similar problems in the UK, first flowering followed by small pods but no further development, there are no bees or pollinating insects in the tunnel and so this year I have researched the problem and selecting self pollinating varieties and will give them a try. Have you considered this possibility?
Beans don't form pods at temperatures above 30 degrees Celsius
That is interesting, and might explain part of the issue I saw in the polytunnel, but not in the outside gardens as we never get that temperature here in Ireland.
You have to pick them. It’s like sweet peas, if you don’t pick them they stop flowering, once they have full sized beans on them they automatically stop. My grandfather would pick ALL the lower beans.
What about light? I know many plants use the sun's wave length to decide if it should produce seeds.
If it's something that always happens at a certain time of year, this could be very likey.
Do they start to produce pods again, as the sun's wavelength changes again? Spring/Fall vs Summer
Try to thin out some of the flowers on a few plants to see if you get more beans produced . This might put more energy into production of beans then flowers.
Same issue in northern Minnesota. Thanks for your interesting insights. I became convinced that leaf hoppers were damaging the flowers. Is that possible?
I hadn’t heard of that, and don’t know if we have them here
It sounds a bit like June drop in apples.
I have not seen a single bumble bee on my runner beans in the uk yet. I have just two pods developing on large healthy looking plants. This year it seems like lack of pollination is the main problem for me.
That is worrying, hope the pollinators arrive soon.
If I had to bet, I would put my money on not enough water. I'm pretty sure I've had that exact problem and it seems to follow the same pattern. A few years ago I just forgot to water and the beans, which had started to develop, just "dropped" off the vine.
Sounds like it may be a nutrient deficiency to me. Access to certain minerals may be limiting the plants’ ability to properly build their reproductive organs, in the quantities that they initially estimated during vegetative stage. If your soil is drying out and only has moisture in certain areas, then I would expect that this will certainly restrict soil life and the available area for the plant to exchange its exudates for nutrients.
John Kempf talks about ‘critical points of influence’ as stages during plant development that you might find interesting and relevant
I suspect something 'simple' to do with gravity. As soon as there are 5-6 pods, moisture (water, growth hormone transport?) first sinks down into the already existing pods meaning less 'stuff' goes to further down the end of the branch which leads to a deficiency that 'aborts' already existing / formed pods, or stops the succesful fertile production of male/female parts of the flower.
Nature usually doesn't "think" too deep, we need to look for the solution close to the laws that govern plant growth. How knows. Keep experimenting!
Here in Sweden we grow this variety of runner beans exclusively for the flowers and many are not even aware the pods are edible so why not try another variety of beans?? I’ve grown these fore many year’s and noticed the same as you; a rather short productive period and I’ve accepted it as is ;)
That is interesting. I generally accept whatever is produced by these types of plants, but in this case I was hoping to see how much more could be produced.
I fail to see the problem. You seem to of gotten a decent crop.
I have firebeans is my garden. They look very similar. I had absolutely no fruit on it!
A lot of beautiful flowers, but no beans...
What's the name of the vegetable, boss? it's not here yet. greetings from Indonesian farmers
judging by the size of the bean pod with almost full sized bean in side ...to me your not picking fast enough and early enough. .must pick every day before seeds start to develop if you want tender pods to eat there are always one or 2 that get missed ether because it is deformed you can't leave it to seed that will stop production.
The pods started to drop off before any beans were even big enough to start a seed, so I don't think that was the issue in this case.
My tomatoes “drop their blossoms” in the heat. No idea if it’s the same thing or not
What's your best, most productive and tasty, beans that can grow in the Irish climate?
My suggestion would be a nutritional deficiency, not a N, P or K but a trace element. This is easy to test, add a small amount of rock dust to the compost in one section and do a side by side trial and if it is a deficiency then you will see a sharp drop as you move away from the amended area.
You might be doing everything right, and still not getting full trusses of beans is the optimal performance from the plants POV. My intuition is that plants produce more flowers than fruit as a survival strategy. Plants that produce both male and female flowers skew heavily on male flowers because it requires less resources to *maybe* pass on genes while not spending a lot of resources on a fruit. For a plant that has perfect flowers, producing some flowers that produce some pollen but maybe do not produce the fruit and it is aborted might be slightly more adaptive than producing the exact amount of flowers for exact amount of fruit they can produce given their resources. Their resources being leaf area for carbs, but also water and mineral uptake by roots. Anyway, extra flowers might mean extra pollen from non-fruiting flowers gets spread about that might turn into seed on other plants, which genes spread to more offspring.
And this might not be a bad thing for us. Ultimately we care about mass per square area or calories per square area. Though, it's complicated. Mass includes water weight, which varies. Calories do not take into account other nutrients, like vitamins and minerals. Mass per area won't take into account vitamins and minerals either, but mass fills your belly. Pick your poison, right?
If you are comparing apples to apples, and the calories/nutrients are roughly the same between the same species/varieties, which every plants produce the most mass/area are the ones you want to favor, and not worry about pods per truss. You can ignore the aborted fruit and just measure the finished fruit.
Ah, now I wonder if the genetic origen of the seed has something to do with that. You may have forgotten that in these Islands Runner bean plants were not planted or bred for the beans. They were planted and tended for their flowers. They originated in Mexico and were brought to Europe as flowers. Like sweet peas which are genetically peas but bred for a very long time for their flowers they have stunted pea pods. I'm wondering if the flowering genetics outweigh the seed genetics when it comes to these plants and maybe as you collect your own seed, after a few seasons that could be a factor in your observations. Just wondering, that's all.
I'm not well versed in the native plants in your area. But I'm wondering if there aren't any native wild bean plants in your area there could be a lack of nitrogen fixing bacteria in the soil for the beans to pair up with. I know in some cases people will inoculate their beans with the correct bacteria before planting them.
That is an interesting point. I do remember finding some nitrogen fixing nodules on these plants, but perhaps more would help. When I first started growing in this area, I noticed that there were no nodules on the peas and beans I was growing, probably because this field had only been growing grass for decades. So I brought a bit of soil from my old garden where `I had grown peas the had produced lots of nodules, and added it into he rows when sowing the peas. It worked, and I think it owed probably be a good thing to do every time I sow beans and peas.
Mist spraying flowers is supposed to improve pollination?
I had heard that, and also read that it can also prevent pollination. In this case there was full pollination then suddenely nothing on any of the trusses and nothing changed as far as I am aware.
I'm no expert but I saw another You Tuber say that you should harvest beans when they are younger so that the plant does not think "I've made my seeds so now I'm done." You seemed to be harvesting very large beans.
Have you measured the CO2 in your poly tunnel? CO2 is a plant food. Most commercial growers increase CO2 to about 800 ppm in greenhouses. Outdoor CO2 has limits and thereby limits plant growth. Plants can grow only as well as the least available nutrient.
Hope you figure out your mystery!
Your in Ireland? You sound like an American!
A Canadian in Ireland.
Get rid of leaves big ones not all leaves