When buying fresh artichokes, look for compact globes, heavy for their size, that yield slightly to pressure and have large, tightly clinging leaves.
Artichoke size has nothing to do with maturity or eating quality. Large and medium-size are best boiled or steamed and eaten leaf by leaf with a little mayonnaise or stuffed. Small ones are best for marinating or for use in stews and casseroles.
Artichokes will keep four to five days in the refrigerator crisper.