Fruit production and seed set is typically low. Fruits and seeds typically not produced in California. Seeds ellipsoid, 4-6 mm long, with a short beak less than 1 mm long. Base of beak collared by wart-like cells. Stem turions axillary, sometimes terminal on monoeicous plants or under certain conditions, tough, green, conical to ovoid, 3-12 mm long, deciduous.
Plants decompose rapidly.
Common elodea may turn blackish and die-back during the cold season or survive green and intact under ice in near freezing conditions. Turions survive near freezing temperatures. Highly susceptible to iron deficiency. Does not survive prolonged periods of near freezing temperatures. Tolerates some shade, little turbidity, and near freezing temperatures.