Both species grow throughout California, except the Great Basin and desert regions. Alameda, Contra Costa, Los Angeles, Napa, San Luis Obispo, San Mateo, Santa Barbara, Solano, Tulare, Yolo. Most seed falls near the parent plant. Some seed disperses short distances with wind and to greater distances with water, soil movement, and by clinging to the feet, fur or feathers of animals. Seed production and viability is highly variable, depending on out-crossing and presence of pollinators.
Seeds germinate in spring and fall when conditions become favorable.
Germination occurs on the soil surface and to a depth of 3 cm. Plants can rapidly colonize a site by vegetative reproduction from creeping roots. Dalmation and yellow toadflax can hybridize. Seeds produced early in a season have a longer dormant period than seed produced later. Under field conditions, seed may remain viable for up to 10 years.