Ask Mr. Smarty Plants

The short answer to your question is "no". There is not an official Lady Bird Johnson Wildflower Center definition of native plants, but it's not from lack of thought and effort. It has been discussed and worked on for years, and is a question we often ask ourselves. There is an excellent previous answer to a Mr. Smarty Plants question that should give you a lot of good information.

As specifically referring to Mr. Smarty Plants, when we are asked a question about a specific plant, we first check our own Native Plant Database. If the plant is not there, then we do wider research. Not all plants native to North America are necessarily on our database, but in our research, if we discover that the plant in question originated somewhere other than North America, we treat it as a non-native. We try to direct those wanting help with a non-native to resources to help them, but the focus is always on plants native to North America, not including Mexico.