The Chinese waterchestnut (Eleocharis dulcis) or waterchestnut is the only vegetable that remains crunchy no matter what you do to it. You can boil it, fry it, can it, or pickle it, and it still is just as crisp and as nutty as it was when you harvested it.The waterchestnut is a staple of East Asian cuisine, something you have probably cooked with or had at Chinese restaurants a thousand times. And the Chinese waterchestnut is something you can easily grow in your own back yard.The waterchestnut has a clump of simple rush like plant with green stems up to 150 cm tall, with no leaves and no branches. A few centimetres below the surface, the plant produces several roundish structures called “corms,” sort of a cross between a bulb and a tuber. Each corm is about 2 cm across, looking rather like a chestnut. It is deep reddish-brown outside, white inside. These corms have a unique cell structure, visible only under a microscope, enabling them to remain crispy under all sorts of conditions.The waterchestnut is a tropical plant requiring 7 months of warm weather to reach maturity. Despite the name, the waterchestnut does not grow in open water next to the water-lilies. It is marsh plant requiring mud so if you want to grow them, you need to create an artificial marsh, sort of like a rice paddy.You can use an old bathtub or you can design an artificial marsh lined with concrete or some other impermeable lining. Use rich soil with plenty of compost mixed in. Spread it uniformly, at least 10 cm deep. Plant corms about 5 cm deep two per square metre. Keep the ground wet until the stems are at least 10 cm tall. Then flood the paddy to a depth of about 7 cm. You might want to add a few fish to control mosquito larvae. (If you have birds, then add some lilies to give the fish a haven from birds who might fancy them.)Keep the water at this depth the entire growing season, until the stems turn yellow. Drain the water. This will allow the corms to harden. Leave them for about a month or so, then dig them up. Wash off the mud and place them in the refrigerator to keep them fresh until you need them. You can freeze them, but do not freeze any that you want to keep for planting next year’s crop.To eat the water chestnuts, peel away the brown skin, and slice the rest. Mix them with assorted other veggies to make an Asian stir-fry, or use them in salad, pasta dishes, omelets, whatever your heart desires. They are about 60% starch, the rest high in fibre, vitamins and minerals.Image: P.Kanchana/Shutterstock