Callitriche hamulata, commonly known as Intermediate Water-starwort, is a perennial herbaceous plant that is often submerged, belonging to the Plantaginaceae family. It is characterized by slender, branching stems that can grow 8-28 inches long. The leaves are light green, narrow, and slightly broader at the tip, with shorter, wider floating leaves that may appear light brownish or pinkish green. This species produces tiny, inconspicuous green flowers and fruits, with a flowering season extending from May to October. Native to a variety of aquatic environments, including streams, ponds, and ditches, it is particularly prevalent in slow-moving or still freshwaters in Greenland, Iceland, and Europe.

Intermediate Water-starwort is valued for its ability to oxygenate water and provide habitat for aquatic organisms. It is used in water gardens and ponds for its ecological benefits and its subtle texture. In cultivation, it requires aquatic conditions, thriving in full sun to part shade and preferring clean, nutrient-rich waters. While not commonly afflicted by diseases, it can spread aggressively in some regions, outcompeting native aquatic plants. Gardeners should be cautious of its potential to spread when introducing it to natural water bodies.CC BY-SA 4.0