Those beautiful plants in your water garden may be more than just another pretty face. Many of these plants we consider strictly decorative have been grown and gathered for centuries as food in their native land. You can do the same in your own backyard. Whether you’re lucky enough to have a pond or stream on your property, a boggy area where water collects, or a fountain you’ve added, you’ll find many aquatic or semiaquatic plants that are not only attractive but also edible — and even delicious.
Most common water garden plants found in nurseries are tropical, originally coming from areas of the world where water is abundant. Thailand, Cambodia, Vietnam, Sri Lanka, New Guinea, India, China and the Amazon region have all contributed plants to the assortment now found in U.S. nurseries.
Before you begin to plant or harvest, please note a couple of important caveats: Socrates killed himself by drinking hemlock tea — a potent water plant. He knew what he was drinking, but you might not know what you’re harvesting. Be very certain what plant you’re actually dealing with before anyone takes the first bite. Also, don’t harvest plants out of bodies of water that have been chemically treated or that are fed by runoff from chemically treated or fertilized yards.
With those warnings firmly in mind, here are some suggestions for tasty edible water plants you could grow in your own water garden.
Some plants, such as watercress, float in the water; some, such as lemongrass, grow along the edges in bogs. Still others, such as water lilies, grow in deeper water with only their leaves above the surface. Wherever in the water they grow, they can add grace to the landscape and flavor to the palate.
Lemongrass (Cymbopogon citratus) is a familiar herb grown in bogs, wet garden soil and along the edges of shallow water gardens. It also grows well in ordinary, damp soil. This tasty herb grows up to 4 feet high and equally as wide and is known for the fleshy base of the grass stalks that grow on top of the ground. The bulbs (not really bulbs at all, but fleshy bases to the clumps of grass) are harvested and the leaves removed for use in various Asian dishes.
Soup, chicken and shrimp all marry well with lemongrass in simple dishes made from this useful bog plant. To experience the true flavors of lemongrass, next time you visit a Thai restaurant, order the Tom Yum Goon soup.
A related species, East Indian lemongrass (Cymbopogon nardus), is the source of citronella oil, used in candles to repel mosquitoes. This variety also is pleasant in tea and potpourri mixes.
The leaves of lemongrass, above the bulbous base, are used in a variety of ways. I make cheesecake, muffins, pound cake and cookies, using the leaves rather than the stalks.
When you make a cake or other dessert using lemongrass leaves, snip the leaf into small pieces with scissors, then blend with the recipe’s liquid.
For muffins or cake, I heat the milk the recipe calls for, add the lemongrass and process in a blender until the grass is chopped fine. This pulverizes the leaf and further extracts the flavorful oils into the warm milk. It’s easy, simple and works perfectly.
Cattails (Typha latifolia). Believe it or not, all parts of the cattail are edible and delicious, from the young shoots, which are eaten raw, to the pollen, which is added to biscuits or pancakes. Cattails are easy to grow at the edge of large ponds, or can be grown in containers of soil set into the pond. They can become invasive if allowed to run rampant, so harvesting them regularly for the kitchen can help keep them from spreading.
Pick the cattail shoots when the leaves are no higher than 2 to 3 feet above the water, and peel off the outer leaf leaving the tender, inner stalk. Wash them in water to which you’ve added a splash of vinegar. Cut in 8- to 12-inch pieces and serve with your favorite dip (I favor sour cream and chive). You’ll be amazed at the fresh, delicious flavor of cattail stalks.
The very tastiest cattails are the ones that have not come up above the water yet. Harvesting them means wading in the water in February and cutting the stalks below the water level. I’ve done it and it’s not as unpleasant as it may seem. But then, I live in Arkansas. Readers in Minnesota might have a different experience. Washed, steamed and served with a bit of butter, these tender stalks taste like the sweetest sweet corn.
Sweet flag (Acorus americanus) is a North American native plant that forms colonies along the edges of ponds, in wet fields and drainage areas.
A. calamus is a native of Europe, naturalized in Britain and is similar to our American sweet flag. You easily can grow either of these sweet flag varieties in containers of soil along the edge of your pond, much as you grow cattails (although cattails require a deeper soil and can withstand deeper water).
Sweet flag historically has been used as medicine for indigestion, stomachaches, colds and coughs. American Indians are said to have carried pieces of the dried roots on long journeys and nibbled the pieces as a stimulant and to assuage thirst. In India, the roots are considered aphrodisiac, while folk uses in Europe include using the roots as a substitute for cinnamon and ginger. The mature leaves repel insects when crushed and rubbed on the skin, and have been used in churches as strewing herbs (herbs strewn on the floors to scent the room when walked on) — two uses, which may or may not be connected. I attended a wedding where sweet flag covered the floor and the room was deliciously aromatic as the wedding party walked on the sweet, spicy leaves. In American frontier times, the leaves and dried roots were used to scent cupboards and clothes closets.
The rootstocks, which grow horizontally, can be candied (similar to candying orange peel), or made into soup. Inner leaf stems are used raw in salads, and the florets can be used along with the roots in soups.
Caution: Not all flags are created equal, so don’t confuse sweet flag with blue flag (wild iris, Iris spp.). Wild iris roots are odorless, taste bad and are poisonous. Sweet flag roots smell great and have a sweet flavor when touched to the end of the tongue. Wild iris/blue flag also have dull, blue-green, odorless leaves; sweet flag leaves are aromatic, glossy and yellowish green. It’s easy to distinguish between the two if you observe the differences in the plants and the fragrance.
Four-leaf water clover (Marsilea quadrifolia) is a small herb that grows in shallow pools, edges of ponds, containers or on wet banks. The rhizome is slender and creeping. If grown in shallow water, the leaves stick up above the water about 3 or 4 inches but if grown in deeper water, the leaves appear to be floating. The leaves close at night.
The shoots and leaves are rich in Vitamin A and the Thai people enjoy them as a raw vegetable, generally by dipping them in hot sauces, such as nam phrik kapi — a shrimp paste sauce with chiles — or nam phrik plaa raa — a fermented fish sauce with fresh chiles. The flavor of the four-leaf water clover is tart and pleasantly astringent, a bit like French sorrel. When you use water clover in soups, add it just before serving to preserve the delicate flavor.
Attractive and graceful, Vietnamese cilantro (Polygonum odoratum) is a tasty herb for Asian dishes or salsas. Easily grown in damp garden soil in a sunny site, it is equally happy in a pot half submerged in the water garden, where it can drape over the pot’s edge and float in the water. This plant will put out rootlets much like watercress. Harvest it often, as the fresh, new tops taste noticeably better than the older leaves and shoots.
More Water Garden Plants for the Table
Water mint (Mentha aquatica) grows on the edges of ponds and water gardens. The leaves and flowers are delightful flavorings for ice cream, mint juleps, syrups and sorbets.
Chameleon plant (Houttuynia cordata), a plant we think of as just a pretty plant for the water garden, is considered a vegetable in many Asian countries. The leaves are lemony with a slightly bitter flavor and combine well in the balance of hot, bitter, sweet and sour flavors in many Asian dishes.
Giant water lily (Victoria amazonica). The dried seeds are popped like popcorn.
Fragrant water lily (Nymphaea odorata). The tender young flowers, young leaves and flower buds are all edible (young flowers raw, other parts cooked).
Rice (Oryza sativa). Yes, you can grow rice in your water garden.
Water chestnuts (Eleocharis spp.). You can grow water chestnuts but they’re a slow-growing crop that might take years to reach harvest.
Water spinach (Ipomoea aquatica). Also known as kang kong, its leaves and growing tips are eaten steamed like other greens. Can be grown in a pot, partially submerged, or in wet soil.
Watercress (Nasturtium officinale). Watercress requires running water for growth. It floats on the surface along the edges of moving streams, with tiny rootlets that reach into the rocks and soil. It is delicious added to salads, dips and sandwiches.
Jim Long is an Herb Companion contributing editor who writes from his home in the Ozarks and enjoys traveling throughout the United States and around the world discovering, learning about and sharing his knowledge of herbs.
For wonderful recipes using water herbs, please select SWEET FLAG CANDY, SWEET FLAG SOUP, GREEN CHILE DIP (NAM PHRIK NUM) or FOUR-LEAF WATER CLOVER DIPPING SAUCE (NAM PHRIK KAPI)