Water Sweetgrass Plant Care

Water Sweetgrass (Glyceria fluitans) belongs to the Poaceae family within the Glyceria genus. Water Sweetgrass is native to Europe, the Mediterranean region and Western Asia and occurring in wet areas such as ditches, riverbanks and ponds. Water Sweetgrass is also known as Floating Sweetgrass, Manna Grass, Floating Mannagrass.

Water Sweetgrass displays a clump-forming perennial grass growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Water Sweetgrass produces small, inconspicuous flowers on tall stems.

Leaf size: approximately 12 inches.

Glyceria fluitans requires watering every 3–5 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.

Water Sweetgrass thrives in full sun to part shade.

Glyceria fluitans grows best at temperatures of 50–80°F. Water Sweetgrass prefers humidity levels of 40–70%.

Moist, fertile soil with good drainage. Good drainage is essential for Water Sweetgrass to prevent waterlogging, which leads to root rot and fungal issues.

Feed Water Sweetgrass every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.

Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Divide clumps every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.

Water Sweetgrass can be propagated through division, seeds. Similar propagation techniques also apply to sharpflower sweetgrass plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Water Sweetgrass is susceptible to aphids, grasshoppers, leafhoppers. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Water Sweetgrass grows outdoors in USDA Zone 4a – 9b. It survives winters down to planting zone 4a. Water Sweetgrass is native to Europe, the Mediterranean region and Western Asia and occurring in wet areas such as ditches, riverbanks and ponds.