[Totty]

Hi all,

This is the firsy year on the allotment for me and my family, things are doing well, could anybody tell me the problem with beans cross pollinating please?

I have been given two lots of runner bean seeds to grow this year, one lot a red flowered variety that my grandparents have saved seed from for 30 years or more and is extremely high yeilding, and one lot of seed from a local gentleman, which has white flowers and lovely straight, stringless beans again seed saved for many years.

Not knowing any different, i thought the two would look nice together in rows but after reading around, i am concerned that when they cross pollinate, the resulting seed will be useless.

Am i right to be concerned or could the resulting seed taken from two strong plants exhibit the plus points of both varieties?

Thanks for any help.

Totty

[Paul Plots]

I suspect it's a bit of pot luck when it comes to crosses. But, I wouldn't worry overly about using saved seed next year.

I have a couple of new/bought varieties of runner beans with red flowers, a section of white flowered and then some saved seed from last year as well as climbing french beans all growing on a long bean frame. 

If you use saved seed next year you will get beans that are similar to the ones you grew this year if not identical.

After a couple of years I buy a pack or two of something new rather than risk an unexpected or unusually low yield.

Someone, however, may know better! 

[New shoot]

You may get something slightly different if they cross pollinate but I'd sow a few and see. You might get your own new strain with good characteristics from both.

Have you got any of the original seeds left - they should still be good for next year and then you can grow them separately and keep them true.

[JayG]

Try saving seeds from the plants producing the best-sized, least stringy, and best-flavoured beans and who knows you might be onto a winner!

(From Lotty to Totty-Beans in the space of a year!!) 

[SG6]

They will cross pollinate and the result will be a mixture of what the pollinating bean was. Similarities with the parent plant may come through but no guarantee.

The dominent characteristics will initially come through but these will dilute.

That is how new varieties are made, but the passing on of desired characteristics is never guaranteed, and they may be passed to one bean but not the next one.

Good old evolution and random chance.

[someoneorother]

There's also the consideration that if any of the seeds from packets were F1 hybrids, even if they only pollinated with themselves the resulting seeds would not grow to resemble the plants you got them from. Nothing wrong with them necessarily, but there'll be lots of variation between plants.

Edit: never mind, just re-read the OP and no packets involved. Doh.

[Totty]

Ok thanks,

Spoke to me old grandpapa and he reckons that his beans were originally grown down here (somerset) for 15 years or more, and for the last 15, in london. All the seeds from him grew very well, as have the white flowered ones that have always been grown here, therefore, so he says the two strains should not have too much of a negative effect on one another and that in time if i save and use the same seed each season there should be no long term problems, just a slightly different strain that will eventually be acclimatised to the growing situation that i am giving them??!!???

[mumofstig]

You just carry on sowing saved beans unless the standard of crop declines.
If it does you have to start with new seed for the next year..........easy peasy

[SG6]

Keep selecting the biggest beans that produce the biggest plants with the longest tendrils.
Over 10 to 20 years you can selectively breed a triffid.

[DD.]

My purple climbing French beans crossed with my "Enorma" runners and I got all sorts of combinations.

[Trikidiki]

You are not going to be able to keep a pure strain, simple as that unless you net the beans to keep out any pollinators and provide your own polinators within the cage.

Bees will travel up to three miles to forage, if they are visiting your beans then they are probably visiting all other beans in the area therefore your beans will likely be cross pollinated with one of those other beans. If the bee only visits your beans then you're ok but highly unlikely.

You may be lucky in that the desired characteristics are dominant in the female chromosome and therefore you will appear to have the same bean but its male chromosone could be from anywhere. More likely you will have a hybrid, it may be better than what you had before or very poor.
 
Viva la difference!

[Paul Plots]

Gregor Mendel has a lot to answer for - all that fiddling about with bees and our beans (or was it peas?)      

[Totty]

ok thanks all,

Not worried about keeping a pure strain, would rather grow beans that are selectively the strongest and most productive on my plot. Will see how it goes!

Totty