Limas, scarlet runners, and yardlongs are all different species, and will not cross with each other. Neither will they cross with any of the common beans (either snap or dry).

The various common beans (such as "Rattlesnake" and "Yin-yang") could cross, especially if they are directly adjacent to one another. The degree of crossing in common beans varies greatly - some get very little, and for some the crossing can be extensive. Placing them some distance apart, with other flowering plants between them (such as the limas and scarlet runners) will reduce the chances.

It is extremely rare for common beans (P.vulgaris to cross pollinate. Not much worry there. The runner beans (P. coccineus) will cross with each other but not limas or common beans. Yardlong beans (Vigna sesquipedalis) will cross with each other and sometimes with southern peas (Vigna unguiculata)Lima beans (P. lunatus)cross with other but not any of the above. Zeedmans advice is very good. Adding safety. But as long as you are not planting muliple cultivars of runners or asparagus beans, you should be ok for seed saving.

Thanks guys, I guess I must've gotten confused. I'm glad to know I can interplant my yard longs with my scarlet runners, I think that'll make a really interesting-looking display on an arched stock panel over the walkway between my raised beds. Maybe some marigolds along the edge and then some bush beans, lettuce, onions & radishes. I'm just getting into companion planting and trying to think of some combinations that will be colorful and different.

I hope Oklahoma weather cooperates as I'm looking forward to a great garden with all the things I've learned and the seed I have gotten from trades or people sending them for SASE's. I've really enjoyed these GardenWeb sites! Lots of great people here.

Farmerdilla and Zeedman, you wrote:

The runner beans (P. coccineus) will cross with each other but not limas or common beans. (snip)

It is rare, but runnerbeans and common beans can and do cross. I had a cross several years ago, and it has been fascinating. At first I did not recognise what was happening - a common bean with red and pink flowers? But the flowers looked different from runner bean flowers. The pods were short, rough skinned, sparse, late maturing and the few black seeds they contained were of irregular size and distorted shape.

The following generation I had some cotyledons in the ground and some above. And the most exquisite flower colours imaginable. Peach, pink, purple, pale blue, apricot. The resulting beans were smooth podded and quite variable in type and yield, including just a single yellow pod on one of the plants containing two tiny seeds. One germinated and I got a very strong growing tall plant with large yellow pods and large brown seeds. Another of these second generation hybrids produced small seeds but with the same markings as the runnerbean that I suspect to have provided the original pollen.

All of the offspring of the cross have become much heavier bearing than the original cross. They still have remarkable flower trusses, but the colours are more muted now. They grow strongly and produce very well, especially later in autumn, when the ordinary beans and the runnerbeans have stopped. So far the hybrids haven't really stabilised much. I most often get black seeds now, but some are white or other colours.

It is rare, but if you get a chance cross, it is fun following it up, even though the first filial generation isn't very promising.

Wow, Galina, that was some luck! Intra-generic crosses are not unknown in beans, but they are rare. When they happen, they provide the chance to breed varieties with new characteristics. I grow about 15 members of the Phaseolus genus each year, and hope that I eventually see something similar.

In 2006 SSE sent me a runner bean that was epigeal; and since I had been taught that P. coccineus was hypogeal by definition, I spent a day reviewing data on the USDA's collection of runner beans looking for something similar.

I found a match to the one I had been sent... and more. Several of them appear to be crosses with either P. vulgaris or P. lunatus, both in the appearance of the seed, and in the epigeal cotyledon trait that you described. I hope to trial them in the future, if I can figure out how to isolate them.

But you are the first gardener that I have heard of who has experienced such a natural cross. As a rule, isolation by species is still effective for saving bean seed. If by chance a cross DOES occur, it's not an accident... it's an opportunity.

Will bush beans cross easily like Kentucky wonder and blue lakes?

The bush beans you name are p. vulgaris and they can cross but not 'easily'. Flower stucture is the usual way that beans avoid crossing. The flower stays enclosed until after pollination, then opens up. Sometimes a bumble bee disrupts this by tearing the blossom open and pollinating the pistil with pollen from a different variety.

DarJones

So in general you can or can't grow pole beans,bush beans together I'm not new to growing the just gonna start saving seed this year with my beans

sgtraven,

I assume you are asking about common pole beans and common bush beans. Common beans, either pole or bush can usually be grown together with no crossing. It can happen, and it has happened in my garden, but normally does not. Just to be sure, you could put a little distance between your different varieties of beans so they are not in adjacent rows or trellises. You can probably get away without doing that though.

Evidence of an accidental cross shows up as wrong color of flowers or wrong seed colors or markings when you grow the saved seed.

Beans and tomatoes are two crops which are self-pollinating, which makes them easy for seed saving.

Jim