Leaf or Chinese celery, Apium graveolens var. secalinum
If you live in a warm climate this is the celery to grow, as the more common stalk celery, Apium graveolens var dulce, which originated in Italy, really requires a cool climate to develop tender long, mild flavoured stalks. Leaf celery grows for a couple of years before being spent and provides a plentiful supply of tender shoots which are indispensable when making stock ,soup or stews. They can also be added to stir-fries. It needs regular water during the growing season and a thick mulch around the plants is beneficial. Mulch can also help to blanch the lower leaf stalks which gives them a better flavour. This leaf celery is also a fairly common wild foraging plant being found in marshy swampy areas usually close to the coast, though the taste may be stronger than a cultivated plant. As the leaves resemble flat leaf parsley, it was marketed a few years back as Australian sea parsley but given our fairly conservative and unadventurous taste for new things it disappeared from the nurseries fairly quickly.