pea inoculant

[otorongo]

I'm growing peas and I'd like them to fix their own nitrogen. Do I need to inoculate them or does my soil already have the right bacteria?

I've read on a US-centric website that outside of Europe one needs to inoculate them while in Europe the soil already has the right stuff, but there may not be enough of it.

If I do need an inoculant, can I apply it to mature plants?

[Kleftiwallah]

All legumes fix nitrogen from the atmosphere and a little from the earth and 'store' it in tiny nodules on their roots with no help from us. That is why it is better to leave the roots of legumes in the soil when clearing the ground as the nitrogen can then be available to other crops.

I think you're reading a document dated the first of April! Cheers, Tony.

[otorongo]

All legumes fix nitrogen from the atmosphere and a little from the earth and 'store' it in tiny nodules on their roots with no help from us. That is why it is better to leave the roots of legumes in the soil when clearing the ground as the nitrogen can then be available to other crops.

Legumes fix nitrogen with the help of special bacteria, e.g. Rhizobium spp. The inoculant for different legumes is a specific species of bacteria that has co-evolved with that particular legume. If you don't have the right kind of bacteria for your legume, it can't fix nitrogen. If you grow an Australian acacia species in Australia, it will normally fix nitrogen because the bacteria occurs naturally in the Australian soil, but if you grow it in the UK, you don't normally have the bacteria in your soil unless it has been artificially added (e.g. by bringing soil from Australia and mixing it into your soil, or by applying a lab-bred inoculant). You can still grow them as "normal" plants and feed them with fertiliser.

My question is whether I need an inoculant for peas or my backgarden soil already has the right kind of bacteria? I don't think any peas have been grown here in the last 30 years. (With the exception of sweet peas).

[taff]

I've read on a US-centric website that outside of Europe one needs to inoculate them while in Europe the soil already has the right stuff, but there may not be enough of it.

If I do need an inoculant, can I apply it to mature plants?

You just answered your own question. Toto, we're not in Kansas anymore, you're in London, in Europe, where peas fix their own nitrogen.....

[Two_Sheds]

it is better to leave the roots of legumes in the soil when clearing the ground as the nitrogen can then be available to other crops.

Nope, it's not. The pea uses up its nitrogen stores when it makes pods. There is little or no nitrogen left in the roots after harvesting the crop

[otorongo]

I think I'll buy an inoculant and inoculate my future pea plantings anyway, to be on the safe side and to give them the best start possible. For you guys growing peas on allotments there would be no point as you most certainly have a good Rhizobium buildup already, but my garden has been grown for ornamentals for at least 30 years and this is the first season it's used for food, so it may be lacking the stuff.

[rustylady]

I think you're wasting your money Otorongo, but then that's up to you.

[alldigging]

Nope, it's not. The pea uses up its nitrogen stores when it makes pods. There is little or no nitrogen left in the roots after harvesting the crop

Aren't the little pale nodules on the roots the fixed nitrogen?


Hmm maybe not
Nitrogen-Fixing Nodules on Pea Roots
say they are nitrogen fixing nodules... so presumably the nitrogen is used straight away by the plant

[rustylady]

Aren't the little pale nodules on the roots the fixed nitrogen?

Nope, they are where the nitrogen was stored but it's used by the plants when forming pods. It's still worth digging the roots in or adding them to the compost heap though.

[zazen999]

I think the latest concensus is that they fix it but once the peas themselves are formed, they draw it back into the fruits.

So, if you want to use peas to fix nitrogen - mow them down before they flower.

If you want to spend money on innoculant, why not just buy nitrogen fertiliser? Or am I missing something here?

And if you want to save your cash - just use nettles. You would be better off buying a bucket and a good sturdy pair of gloves to harvest your nettles to make your own brew IMHO.

[miker2d2]

my soil in my garden has the correct bacteria - i have grown legumes for years - i will quite happily sell you a handful for a tenner so you can innoculate your soil

[Kaiya]

MPC presumably won't have the native bacterium in either, yet peas do fine in that. I grew peas in my garden soil which hasn't even grown ornamentals before (new build, someone else's lawn before) and they did fine. Sweet peas and lupins (also legumes) are often grown in garden soil without issue. So I agree - sounds like a waste of money to me.

If you do spend money on it, consider a trial - some with, some without. Then you can see whether it was worth it.

[Potstubsdustbins]

I don't know how much this stuff cost's but £7 worth of Miracle Gro last me 2 years and is very high in nitrogen.

Colin