Frogbit
Hydrocharis morsus-ranae

European frog-bit is a small, free-floating, aquatic herb, remeniscent of a tiny water lily. It has nickel sized, round, smooth, leathery, green shiny , heart-shaped leaf blades that reach a diameter of about 1 in. (5cm.) that grow in rosettes on the water.

The lower surface of the blades is usually dark purplish-red in colour and the undersides of the leaves are puffed with spongy, air-holding tissue, helping in the floating quality. The floating blades have elongate stalks, 4-6 cm long, and form a rosette from the short submerged stem. Horizontal runners form at the base of the plants and give rise to new plantlets at their tips. Long unbranched dangling roots have the appearance of elongate narrow bottle brushes due to the dense cover of green root hairs. By mid-summer dense mats of interlocking plants form over the surface of the water. A single white flower, about 1.5 cm in diameter, having a small yellow area at the base of each of the three petals, is borne at the top of the 8-10 cm long flower stalk. ]

Habitat: Its preferred habitats are quiet, open water in marshes, ditches and swamps. When present along river shorelines or streams, plants are generally found in quiet backwaters. By mid summer, extensive vegetative growth results in the formation of dense floating mats of intertwined plants.

Frogbit is a good choice for a small garden pond or minipond because growth is restrained and a succession of small and short-lived white flowers appear in summer. In autum the folage starts to die away and the plant survives at the bottom of the pond in the form of dormant buds. In early summer these rise to the surface and growth begins again. When not in flower,

Plant overwintering is only possible indoors in an aquarium.

European frog-bit overwinters primarily by forming small vegetative buds called turions that are formed at the base of the plants and at the ends of the stolons. These turions sink to the bottom as the plants deteriorate late in the year and then float to the surface in the spring and develop into a new crop of plants. These buds apparently only grow if they have overwintered at low temperatures.

Flower: July-August
Flower heighth above water: 1-2 in.
Propagation: divide clumps in summer.

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