Topic: cross-polination question

[Sarah-b]

Something occurred to me last night: if I grow several different types of beans, close together, will cross-polination occur? And is so, what does that mean? Will I get hybrid beans - or does it only affect the seeds? (Have forgotted everything from my biology lessons).

Thanks,
Sarah.

[DocAlgae]

Hi Sarah,

If you grow several types of beans together, then chances are, they will end up cross-pollinated.  This'll mean your beans will end up with a variety of characters according to the parent plants from which they were pollinated.  If you want to save your beans to plant again next year, probably best not to allow them to cross-pollinate, as you won't be able to predict what the new plants will be like.  On the other hand, evolution is a wonderful thing, so might be worth an experiment!  You could end up with some marvellous new bean variety (or sterile seeds!).

[Tenuse]

How far apart should beans be planted to avoid cross pollination?

Ten x

[tim]

" variety of characters" - only in the next generation?? = Tim

[DocAlgae]

Yep, that's right Tim - sorry for the confusion!

Basically your initial batch of cross-pollinated beans will be fine and dandy I would think.  Your weird varieties would come in the second gen.

(bad day at work - not making myself clear!)

[Sarah-b]

Have just been reading a seed-saving site and apparently "Beans produce perfect, self-pollinating flowers. Cross pollination by insects is possible but rare as pollination occurs before the flower opens."
That's handy then...

[john_miller]

Indeed Sarah, legumes have, from a bees point of view, one of the most difficult flower structures to collect nectar from. This structure has evolved to, as near as is possible in the plant world, ensure that the bee cannot help but pollinate the flower when it is leaving following nectar collection- bit like Orchidaceae!

[philcooper]

It depends on the bean.

French, as John says are perfect flowers, and are unlikely to cross pollinate, a separation of 20yds between varieties will almost guarantee the strain is kept pure

Runners are the opposite and cross pollinate very easily - on an allotment you may have difficulty keeping you varieties pure.

Broad beans are in between, if you plant in blocks then those in the centre should be pure, whereas those around the edges may well be hybridised.

The HDRA have seed saving guidlines on its members website