Sagittaria graminea

The Sagittaria sagittifolia 'Flore Pleno', also known as arrowhead, is an aquatic perennial plant. Sagittarias have phosphate-removing properties used in wastewater treatment. In this variety, beautiful double white pompoms bloom in summer among the lance-shaped leaves. At the base of the flower, there are some purplish nuances that enhance its charm. Despite its exotic appearance, this aquatic perennial is hardy.

The Arrowleaf Sagittaria belongs to the family Alismataceae. It is a tuberous plant of horticultural origin, 60 cm (24in) tall. The wild form is widespread in water bodies in temperate regions of Europe, Russia, and China. Flowering occurs in July-August. The flowers are arranged in whorls of three along the stem, with male flowers on top and female flowers below. This plant exhibits a peculiar feature: it has three types of leaves, a phenomenon known as foliar polymorphism. The submerged leaves form long ribbons of 1.20 m (4ft) and can create real aquatic meadows. The floating leaves are rounded and heart-shaped, while the emergent leaves out of the water are arrow-shaped and acute. The underground stem produces numerous shoots ending in tubers, which serve for propagation.

Arrowheads are used as phosphate-removing plants at the edges and in stagnant artificial or natural waters, natural streams, shallow waters, and marshy gardens. To prevent them from becoming too invasive, they can be planted in containers submerged in basins. They can be used decoratively in a water feature or in an aquatic container on the terrace. This plant, in its wild form, is considered invasive in the USA.