Peas are not supposed to be hard when cooked and instead should be soft and easy to chew.
If the peas are hard after cooking they could be too old, overcooked or not cooked long enough.
Cooked peas can be hard when they are not cooked long enough or if they are old and have been stored too long.
The older the peas are the longer they will take to cook and soften and sometimes they never get soft if they are really old.
Peas that were picked out of season or frozen too long after being picked can cause the peas to remain hard after cooking.
Overcooking the peas can also cause the peas to become hard and shrivel up.
For fresh peas, cooking the peas for 90 minutes should soften then enough but if they are still hard after a few hours of cooking then the peas are likely too old.
Fresh peas will often cook in boiling water within 25 to 35 minutes.
The older the peas are the longer they will take to soften.
Cooked peas are done cooking and ready to eat when they're bright green and tender but still have a slight bite.
You can eat the peas raw or cooked, but if you choose the latter, make sure to cook the peas for only a few minutes to maintain their sweetness and crunchiness.