Plant · P-303

Common Sorrel

Rumex acetosa

Common Sorrel's lemon-sour leaves are the reason to grow it - raw or cooked in salads, pureed into soup, or dried for storage - and the same plant also yields edible flowers, a cooked root, a bread-flour seed, and a leaf juice strong enough to curdle milk as a rennet substitute. Its hardiness tops out well short of a hot summer, so rather than the long-lived perennial the books describe, it behaves best as a cool-season crop that bolts and turns bitter once nights stay warm, best resown each autumn rather than nursed through summer. Its leaves carry enough oxalic acid to bind calcium and aggravate arthritis, gout and kidney stones, so eat them sparingly rather than daily, and cook them to cut the oxalate load.