Peas - round or wrinkled?

[veggiechicken]

I'm puzzled
You can sow Round seeded peas in the Autumn but wrinkly ones wait until spring.
So, my question is, why the difference in appearance and sowing time?
If Autumn sown peas need to be tougher than spring ones, why aren't they the wrinkly ones?
Answers on a postcard please................

[Thelma Sanders]

The round ones have such tough skin that they don't wrinkle ...............perhaps

Or that round ones are fatter which gives them some insulation against the cold..........although that doesn't work for me LOL

[veggiechicken]

Know what you mean, Thelma If I was a pea I'd be wrinkled and round

[Bigmallly]

If you like starch, this'll frazzle your brain:

Round & Wrinkled

[veggiechicken]

So one can't be wrinkled and round, wrinklies are the little sweeties Sounds like everyone's dear old granny

[Bigmallly]

Sounds like it..........the round peas contain more starch, the wrinkled ones, more sugar so sweeter. So why are garden peas so sweet?..........

[Penellype]

Having read that article, the difference between the 2 types of seed appears to be in the amount of starch in the pea. The starch is the pea's food supply. Round peas have more starch than wrinkly ones, so perhaps they are better at feeding the plant during slower development in low sunlight than wrinkly peas which cope better when there is more sunlight in the spring. Just a guess.

[veggiechicken]

Did you ever do that thing in school where you put a piece of bread (starch) on your mouth and let it dissolve and it turns to sugar. Something like that anyway
You could do that with round peas............

[Penellype]

Sounds like it..........the round peas contain more starch, the wrinkled ones, more sugar so sweeter. So why are garden peas so sweet?..........

The wrinkles don't appear until later when the peas dry out, so all peas are round at the harvesting stage. At this stage the sugars have not yet turned to starch, although if you harvest older pods you will find they have lost the sweetness and are much more powdery and starchy.

[veggiechicken]

But why don't the round ones dry out and go wrinkly?

[Penellype]

Did you ever do that thing in school where you put a piece of bread (starch) on your mouth and let it dissolve and it turns to sugar. Something like that anyway
You could do that with round peas............

Yes, the enzymes in your saliva break down starch (which is too big a molecule to be absorbed by the body) into its smaller component molecules, which are sugars. This is exactly the opposite to the starch building process which is inhibited in the wrinkled peas.

[veggiechicken]

Thanks Penellype. You can tell I was no good at science
Having read that article again, wrinkled peas take in more water and plump themselves up to fill their skins - like Botox I suppose. Then when the water evaporates, their wrinkles return. Whilst the round peas stay fat and happy

[Penellype]

But why don't the round ones dry out and go wrinkly?

This is to do with the osmosis process. Water molecules are small enough to go through cell membranes, starch and sugar are not. Therefore a high concentration of sugar or starch will suck water into the cell (think of how your hands swell up if you keep them in water for a long time). But starch molecules are long chains of sugar molecules and they don't dissolve very well, whereas sugar molecules are smaller and more soluble. The sugar molecules therefore cause much more water to be drawn in than the starch molecules do, and this means the skins of the peas are more stretched. This will happen over quite a long time, whereas in the round peas the sugars will be turning into starch. Then when the peas dry out the wrinkly ones will have loose skins which wrinkle, but the round ones will have tight skins around all that insoluble starch.

[veggiechicken]

And this is what I love about the Grapevine - there's always someone who understands and knows the answer - and I learn something new everyday
Thanks BigM and Penellype
Now to find some round seeds to sow in the next few weeks

[veggiechicken]

If anyone is thinking of sowing Autumn peas, these seem to be suitable:-

Meteor (Oct/Nov & March/April)
Douce Provence (Nov - Feb)
Feltham First (Oct - March)
Oskar (Real seeds - Autumn)
Bijou Giant Sugar pea (Real seeds - Autumn)

Other round peas are available.............