Watermeal: The World’s Tiniest Aquatic Plant for Your Water Garden
Meet watermeal (Wolffia), quite possibly the most overlooked plant in North American water gardens. This tiny floating plant holds the remarkable distinction of being the world’s smallest flowering plant, yet it packs a surprising punch when it comes to supporting aquatic ecosystems and wildlife.
What is Watermeal?
Watermeal is a perennial aquatic forb that floats freely on the surface of still or slow-moving freshwater. These diminutive plants are so small that they often look like green specks of dust scattered across the water’s surface. Don’t let their size fool you, though – watermeal plants are complete flowering plants, just incredibly miniaturized versions of their larger cousins.
As a vascular plant without significant woody tissue, watermeal lacks traditional stems, leaves, and roots as we typically know them. Instead, each tiny plant consists of a simple green body that floats effortlessly on the water’s surface.
Where Does Watermeal Grow Naturally?
Watermeal is native throughout most of North America, including Canada, the lower 48 United States, and Puerto Rico. You can find this adaptable little plant growing naturally across an impressive range of locations, from Alberta and British Columbia down to Florida and Texas, and from coast to coast.
The plant grows in these states and provinces: Alberta, Alabama, British Columbia, Manitoba, New Brunswick, Arkansas, California, Ontario, Colorado, Connecticut, Quebec, Delaware, Saskatchewan, District of Columbia, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, and Puerto Rico. In Hawaii, it’s considered a non-native species that has naturalized.
Should You Grow Watermeal in Your Garden?
The decision to include watermeal in your water garden comes with both benefits and considerations. On the positive side, this native plant provides excellent wildlife value and requires virtually no maintenance once established.
Wildlife Benefits
Watermeal serves as an important food source for waterfowl, providing 5% to 10% of water birds’ diet according to wildlife studies. Ducks, geese, and other aquatic birds readily consume these protein-rich plants. While watermeal doesn’t provide significant cover for wildlife due to its tiny size, its nutritional value makes it a valuable addition to wildlife-friendly water features.
Important Considerations
Before adding watermeal to your pond, it’s crucial to understand its growth habits. In Missouri, watermeal has been classified as having a Nuisance status, indicating that it can become problematic in certain water bodies. Like many aquatic plants, watermeal can spread rapidly under ideal conditions and may require management to prevent it from completely covering water surfaces.
Growing Conditions and Care
If you decide to incorporate watermeal into your water garden, you’ll find it remarkably easy to grow – perhaps too easy! Here’s what this tiny plant needs:
- Water requirements: Still or very slow-moving freshwater
- Light conditions: Full sun to partial shade
- Temperature: Thrives in warm water temperatures
- Nutrients: Benefits from nutrient-rich water but can adapt to various conditions
- pH: Tolerates a wide range of water pH levels
Planting and Maintenance
Watermeal requires no soil, containers, or traditional planting methods. Simply introduce the plants to your water feature, and they’ll begin floating and reproducing on their own. The challenge isn’t getting watermeal to grow – it’s keeping it under control!
Population Management
Due to its rapid reproduction rate, you may need to periodically remove excess watermeal to prevent complete surface coverage. A simple net or rake can help you harvest surplus plants. The good news? The plants you remove make excellent compost material or can be shared with other water gardeners.
Design Role in Water Gardens
Watermeal works best in naturalistic water features designed to support wildlife. It’s particularly well-suited for:
- Wildlife ponds and habitat gardens
- Natural swimming pools (in designated wildlife zones)
- Bog gardens with open water areas
- Rain gardens with permanent water features
- Educational gardens focused on native aquatic ecosystems
The Bottom Line
Watermeal offers water gardeners a chance to grow one of nature’s most fascinating plants while supporting local wildlife. However, its aggressive spreading habit means it’s not suitable for every water feature. Consider watermeal if you’re creating a wildlife habitat pond and don’t mind occasional maintenance to keep populations in check.
For smaller, formal water features or areas where you want more control over plant growth, you might prefer other native aquatic plants that are easier to manage. Remember, successful water gardening is all about matching the right plants to your specific goals and maintenance preferences.
