Botanical Name: Eleocharis dulcis
Some other names: Chinese water chestnut, Somwang, Apulid
How to grow it:
Water chestnut is a perennial sedge plant grown in swampy conditions for it’s tasty corms which are harvested in winter/ early spring. It has long, hollow leaves out of the water.
It grows best in the subtropics/tropics but will still do OK in cooler areas provided there’s over 6 months of warm weather. Does not tolerate significant frosts.
I grow mine in an old bathtub with about 30 cm of soil covered by about 10cm of water and it produces big crops every year. Likes full sun in a warm position of your garden.
To plant, prepare your soil in advance of spring with some old manure or compost and plant corms (2-3 per square metre) in the soil when wet – not flooded. Once the shoots grow to above the level of your container, you can fill with water & the plant will take off without any other help. For bigger corms, it’s important to harvest all of the crop each year, perhaps leaving just a few in your container for the following year. The plant will grow like a perennial, without any help, but without thinning, the corms will get progressively smaller as each year goes by – not good as they are finnicky to prepare for eating.
Corms are a good source of carbohydrates with vitamin B, potassium, manganese & copper.
Using it in the kitchen:
Harvested corms need to be peeled, removing the dark brown skins, First, cut off the top & base then peel the remaining brown skin with a knife.
Once peeled, the corms can be eaten fresh in hand, or chopped & added to salads. They have a slightly sweet, nutty taste and have a crunchy texture.
Cooked, they retain this crunchy texture and can be added to stir fries, curries, soups & casseroles. Very popular in asian cooking.
Since you’ll normally have a glut of corms at harvest time, it’s a good idea to freeze them. The best way to do this is to boil them for a few minutes, drain & cool. I like to freeze them on trays & then store them in freezer bags all separated – that way you can grab a few at a time for adding to dishes for the rest of the year.
A good survival food as they are so easy to grow, and they will perennialise if not harvested every year.