Stupid question alert - earlies , second early, lates

[Containergardener]

Could someone explain these differences please, I have seen them on potatoes but I'm seeing them on peas and things.
I don't know what they mean.

[Andraste]

In very basic terms it's generally an indicator of how long from planting/sowing to harvest.

For spuds it's about 10-12 weeks for 1st earlies, 2-3 weeks more for 2nd earlies and another month or so for maincrop to be ready.

Same thing for peas - earlies about 10-14 weeks then maincrops coming on-line after that.

I'm sure there are more technical aspects too (germination temps etc.) but I'll leave more experienced/knowledgeable grapes to advise you there. x

[ameno]

The above is pretty much spot on. The one thing I would add is that maincrop can usually be further divided into early and late maincrop, with a 15 day or so difference between them, and many late maincrop potatoes are still day length sensitive.
Day length sensitivity means that they don't start producing tubers until the daylight hours reach a certain length. This has been bred out of most potato varieties, such that they can crop at any time of year as long as it's warm enough, but those which are still day length sensitive will not be ready until the late summer no matter when you plant them, which is why there is nothing to be gained by planting them earlier.

[Snoop Puss]

I didn't know that, ameno. Thanks.

[Containergardener]

Thank you andraste and ameno

[peacegarden2024]

the following info might make things clearer.
earlies 70-84 days, 2nd early 85-104 days, main season 105-140 days.