A wildflower (or wild flower) is a flower that grows in the wild, meaning it was not intentionally seeded or planted. The term implies that the plant probably is neither a hybrid nor a selected cultivar that is in any way different from the way it appears in the wild as a native plant, even if it is growing where it would not naturally. The term can refer to the flowering plant as a whole, even when not in bloom, and not just the flower.

"Wildflower" is not an exact term. More precise terms include native species (naturally occurring in the area, see flora), exotic or, better, introduced species (not naturally occurring in the area), of which some are labelled invasive species(that out-compete other plants – whether native or not), imported (introduced to an area whether deliberately or accidentally) and naturalized (introduced to an area, but now considered by the public as native).

In the United Kingdom, the organizationPlantlife International instituted the "County Flowers scheme" in 2002, see  County flowers of United Kingdom for which members of the public nominated and voted for a wildflower emblem for their county. The aim was to spread awareness of the heritage of native species and about the need for conservation, as some of these species are endangered. For example, Somerset has adopted the cheddar pink ( Dianthus gratianopolitanus), London the rosebay willow herb (Chamerion angustifolium) and Denbigshire/Sir Ddinbych in Wales the rare limestone woundwort (Stachys alpina).