Spotless watermeal (Wolffia arrhiza)

Spotless watermeal

Also known as: Least duckweed

Spotless watermeal is the smallest known vascular plant and is found floating on still freshwater bodies of water. In cooler weather, it sinks to the bottom, rising again when warmer weather arrives. Plants grown in wastewater are often fed to carp, tilapia, and chickens.

Scientific classification

Species

Spotless watermeal (Wolffia arrhiza)

Water plantains and allies

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Perennial

Lifespan

Evergreen

Leaf type

20 - 38 ℃

Ideal Temperature

Images of Spotless watermeal

Distribution of Spotless watermeal

Distribution Map

Spotless watermeal is a plant with a widely established natural distribution that spans multiple continents, including Africa, Europe, Asia, and parts of South America. Having originated in various regions across the Old World from temperate to tropical climates, spotless watermeal has been introduced and now thrives in certain areas within South America.

Native

Cultivated

Invasive

Introduced

No species reported

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Care Guide for Spotless watermeal

Every week

Water

Full sun

Sunlight

20 - 38 ℃

Ideal Temperature

Water: Spotless watermeal thrives in humid, consistently moist environments, suitable for aquatic settings. Water weekly for optimal growth. Ideal for indoor cultivation in containers, spotless watermeal benefits from managed water levels, simulating its natural wetland habitat.

Fertilize: For optimal growth, spotless watermeal requires occasional fertilization with a diluted balanced liquid fertilizer applied monthly during warm months and bimonthly in cooler seasons. Over-fertilization risks algae issues, but proper fertilization enhances nutrient uptake, supporting robust health and indicating water quality.

Pruning: Spotless watermeal is a small, fast-growing aquatic plant that requires pruning in early to late spring to control growth and promote health. Techniques include thinning and removing decayed parts. Pruning enhances water quality and ecosystem balance; handle gently due to spotless watermeal's delicate structure.

Propagation: Spotless watermeal is a tiny floating aquatic plant that reproduces quickly through vegetative means, forming dense surface mats. To propagate, provide a calm water environment with sufficient light, and divide mature plants. Proper nutrient management prevents algal competition, promoting healthy populations.

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