Once known as the ‘Persian vegetable’, spinach is native to central Asia, but had been introduced to both east Asia and Europe well over a millennium ago. It shows up in the first English-language cookbook we know of from the fourteenth century as ‘spinnedge’.
Spinach comes in two forms, depending on when it is harvested. Baby spinach is tender and mild, and is best eaten raw in salads, sandwiches, etc. Mature spinach has a more robust flavour and is best used cooked, e.g., in a spinach saag. They don’t substitute well: cooking baby spinach tends to produce flavourless slime.
Spinach is famous for its nutritional value, exceptionally high in a long list of vitamins and minerals. It is worth noting, however, that the nutritional value of spinach declines with storage, even if it continues looking and tasting perfectly fine. Folate, in particular, rapidly disappears.
SEASON: spring (spinach really dislikes hot weather and so tends to be available for only a short period at the beginning of the farmers’ market season in Kentucky)