The main difference between an English pea and a snap pea can be found in the pod. An English pea has a waxier, more fibrous pod. It is not edible, so these peas must be shelled.
A snap pea, on the other hand, has an edible shell that is less fibrous. A snap pea pod is not waxy like an English pea's. However, the membranous string running along the top of the pod should be removed before eating, in a process called "stringing."
Both English peas and snap peas are cool weather vegetables, meaning they are one of the first plants to go in the ground of any home garden. However, they must be picked at different points in the growing process for the best results to reach the kitchen table.
English peas should be left on the vine until they almost reach full maturity. They are best picked when the peas inside the pod are fully expanded, but before they become too hard and lose their sweetness. Also, English peas should only be picked immediately before use because they lose their sweet taste and nutritional value quickly after a harvest. This is why English peas are commonly frozen after harvesting, as freezing them helps keep them tasting fresh.
Conversely, snap peas should be picked before the peas are fully extended, not after. They are best when the pod begins to thicken a little, but before the peas grow large. When snap peas are ready to be picked, the pods will snap much like a bean.
English peas are not usually sold still inside the pod, so this makes them easy to find in almost any supermarket or local grocery store. They are typically sold in two forms: canned and frozen.
Snap peas are sold pod and all, so they are most often found in the produce section of any food market.
English peas can be blanched, baked, microwaved or eaten straight off the vine. They are good in casseroles, pastas, salads or all on their own. However, they must be shelled before eating.
Snap peas, however, are eaten whole, with the peas still inside the pod. They also can be blanched or eaten straight off the vine. They are often found in stir-fry recipes as well as salad and pasta dishes.