Aquatic vegetables are suited to shallow-water environments, and the common types are rich and varied

Aquatic vegetables are vegetables that grow in shallow water, wetlands or paddy fields and can be eaten. Common cultivation environments include ponds, lake shallows and low-lying paddy fields. These vegetables have long adapted to the low-oxygen underwater environment, and most of their stems and leaves contain well-developed aerenchyma. They prefer a warm, humid climate and cannot do without water throughout the growing period.

There are quite a few common types of aquatic vegetables, and they can roughly be divided into several categories by the part eaten. Those eaten for their rhizomes or corms include lotus root, water chestnut and arrowhead; those eaten for their tender stems or tender leaves include wild rice stem, water dropwort, water shield and cattail shoot; and those eaten for their seeds or fruits include fox nut and water caltrop. The flavors of different varieties differ noticeably; some are crisp and juicy, while others are soft, glutinous and sweet.

In terms of cultivation, aquatic vegetables are mostly planted in spring after the temperature warms up. During the growing period, a suitable water level and relatively clean water quality need to be maintained, along with proper topdressing and pest and disease control. Harvest time varies by type; some are picked for tender stems and leaves in summer, while others have their rhizomes dug up only in autumn or winter. Overall, their management depends more on water regulation than that of ordinary upland vegetables.

From the standpoint of usefulness, aquatic vegetables are mostly high in water content and refreshing in taste, and they often appear as summer and autumn seasonal dishes in soups, stir-fries and cold dressed dishes. Types such as lotus root can also be processed into side foods like lotus root powder. For farmers in producing areas, growing vegetables in paddy fields can also be combined with fish farming and other methods, allowing the same field to deliver higher returns.