A cultigen (from Latin cultus 'cultivated', and gens 'kind') or cultivated plant is a plant that has been deliberately altered or selected by humans; it is the result of artificial selection. For the most part, these plants have commercial value in horticulture, agriculture or forestry. Because cultigens are defined by their mode of origin and not by where they grow, plants meeting this definition remain cultigens whether they are naturalised, deliberately planted in the wild, or grown in cultivation.

Cultigens arise in the following ways:

• through the selection of variants from the wild or cultivation, including vegetative sports (aberrant growth that can be reproduced reliably in cultivation)
• from plants that are the result of plant breeding and selection programs
• from genetically modified plants (plants modified by the deliberate implantation of genetic material)
• from graft-chimaeras (plants grafted to produce mixed tissue with graft material from wild plants, special selections, or hybrids).