The decision to select native plants versus non-native plants is a personal one. There is no one right answer. There are appropriate species within each category and inappropriate ones as well.
There is a misconception that all native plants are more drought tolerant than introduced or non-native plants. That depends on the species. It is a statement you cannot take across the board. There will be exceptions in both directions.
Plants need water. Different species require different amounts of water. Some can go for longer periods of time without water than others. But a general premise is: trees grow where there is adequate water for their needs. Here in the Bitterroot Valley of Western Montana, native trees will be found along creek and river beds or in the mountains along drainages where water is more plentiful. The native plants surviving further from water sources are drought-tolerant species such as juniper, Juniperus scopulorum, sagebrush, Artemisia spp, rabbitbrush, Ericameria spp, as well as various grasses and forbs of high plains semi-arid environments. An unfortunate reality is many of our native species are not necessarily suitable for a managed landscape.
People living in areas with abundant rainfall and moderate climates have a plant palette consisting of a large selection of native species. This may enable the homeowner or landscape designer to stay within the native range and still create an interesting and diverse landscape. Those living in dryer and/or colder zones with limited species are going to have a harder time.
Here is, in my opinion, the caveat few take into consideration: there is arguably no species native to the built environment. Once we move into an area and alter the surroundings with hardscape, compacting the soil, bringing in fill from other areas, changing topography, the plants originally “native” to that site are no longer. Or probably a better way of saying it is the site is no longer suitable for that native species.
Then there are people with a flexible definition of “native”. For example, some broaden the limitations from their state to include any species native to North America. To my mind, if they are willing to use an introduced species from across the continent, Canada and Mexico (and then if you want to use the United Nations designation, add the Caribbean as well), why limit yourself?
Trading and exchanging seeds and plants has a very, very long history going back thousands of years. As global trade escalates, so do the pluses and minuses from those transactions. There are many beautiful, exciting plants to enjoy in our landscapes. And, yes, many we should be cautious of. However, non-native is not synonymous with invasive. That is another topic entirely.
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