Ask Mr. Smarty Plants

The word cultivar - short for cultivated variety - is used to describe plants that are found in nature and selected for cultivation, usually because of some characteristic that makes it more attractive to the gardener's eye or one that makes it more successful in the garden setting.  Cultivars also include man-made hybrids and plant selections with genetic characteristics that do not occur in nature. Technically, a cultivar is the same species as the species from which it was originally selected. If one adheres to a strict definition of native plant as one that exists in a given area without direct or indirect human intervention, then cultivars by virtue of the human selection of particular traits would not be considered a native plant. That is probably the reason your native plant society and local native plant nursery do not recognize cultivars.

So, what is wrong with a more robust, floriferous and rampantly-growing cultivar of a native species?  The concern of native plant ecologists and native plant enthusiasts is that by propagating and spreading wildflowers with unusual characteristics, one might change the population genetic structure of the original species.  Moreover, a previously-innocuous species might become a problem weed and an ecological problem within its own native range.