Another variety, golden celery, is grown under paper ore a layer of soil to prevent the greening caused by chlorophyll.  Celery is available year-round.

Buy stalks that are firm and unblemished with leaves that are green, not yellow.  Refrigerate in a plastic bag for up to two weeks.

Celery needs to be thoroughly cleaned.  Pull ribs away from stalk and wash off dirt.  If celery is tough, snap the rib near the top without breaking the stings and pull the piece towards the bottom.  Do not discard leaves, but save for flavoing soups or pasta Bolognese.  Raw celery goes very well with Stilton cheese.  Kids like it with peanut butter or cream cheese packed in the groove.  Braised or baked celery goes great with ham and roast beef.