beans again.

[ann-the-nan]

Now is the time, I am told, to dig the runner plants in. Is that LITERALLY? Should I be burying the whole plant or just the roots? Thanks for any help and advice.

Ann.

[alex-adam]

Traditionally the roots were dug in. The top foliage consigned to the compost heap. Recently there has been some research done which casts doubt on the nitrogen value of the roots. There was a discussion on this on GQT about two weeks ago, you might be able to find a link on the BBC website.

a-a

ADDENDUM- I've found the link: BBC - BBC Radio 4 Programmes - Gardeners' Question Time, Colne

[Aberdeenplotter]

No doubt in my mind and the folks on GQT are no more knowledgeable than many of the folks on this forum. Beans are leguminous and fix nitrogen out of the air into their root system. If you remove the roots from the ground, you lose that nitrogen, so dig them down and get the benefit of free fertiliser.

[Two_Sheds]

The thing about the root nitrogen thing is: the nitrogen is in the roots until the bean flowers, and then the plant takes the root nitrogen and puts it into pod production.

There is very little, if any, left in the roots after pods have formed

[Pies]

I've just cut down my bean plants,tops went into the compost bin roots left alone.They have not been dug up in any way as my cauliflowers will be planted in that patch next year they like firm soil so ive just hoed the area and covered with mushroom compost

[alex-adam]

Hi Aberdeen,

You are of course right on the button, there is more knowledge here than all the gardening programmes put together. (Only we don't get paid for it!!!!)

I did use the phrase ''cast doubt'' so we can each form an opinion.

a-a

[oldie]

Someone posted a link recently to a site which has researched some of the gardening folklore that has been passed down to us. Many of these, including the one about nitrogen nodules have been disproved as TS has pointed out. I can't find the link-anyone?

[ann-the-nan]

beans again.

What a superb lot you are, all of you. I think I know where I am going now - maybe. So, I'll chop the dry pods off, cut them down to the roots, then leave them so I have firm soil for my brassicas. Does that sound OK?

[Two_Sheds]

gardening folklore ...the one about nitrogen nodules have been disproved ... link-anyone?

Here's one, there will be more: Nitrogen Fixing Bacteria - Rhizobia

[Two_Sheds]

Someone posted a link recently to a site which has researched some of the gardening folklore

That was Zazen, it was reported in the Guardian.

A little more explanation here, from http://aces.nmsu.edu/pubs/_a/a-129.pdf:

"nodules on annual legumes generally lose their ability to fix nitrogen, because the plant feeds the developing seed rather than the nodule"

"Some legumes are better at fixing nitrogen than others. Common beans are poor fixers (less than 50
lbs per acre) and fix less than their nitrogen needs."

"The amount of nitrogen returned to the soil during or after a legume crop can be misleading. Almost all of the nitrogen fixed goes directly into the plant. Little leaks into the soil for a neighboring non-legume plant."

[singleseeder]

What a superb lot you are, all of you. I think I know where I am going now - maybe. So, I'll chop the dry pods off, cut them down to the roots, then leave them so I have firm soil for my brassicas. Does that sound OK?

Ann, don't forget to collect the dried beans in the pods ready for resowing later this year.

[ann-the-nan]

beans again.

Thanks single seeder. I thought that's what I put in *8, but maybe I worded it incorrectly. Thanks all the same. All help appreciated.