Gardening Etcetera: Ecoregions: the conditions that determine native adaptation

Everybody always asks “what is native?” or even “where is it native?” The less frequently asked question is “how is it native?” How is it that there are over 250 species of Penstemon in North America — the largest genus of plants found only on this continent? How do the conditions in our region determine which plants pass along their genetic material? What drives speciation?

For a better understanding, we can look to ecoregion mapping to understand the differences in regions, and therefore, how plants have evolved to withstand different environments.