Indigenous plants are, by definition, those native to the specified locale. To qualify, the specimens in question must have been growing in that region for a considerable amount of time (longer than the plants that have merely naturalized in the region). "Considerable" here is, necessarily, somewhat arbitrary. For the Americas, many consider the plants growing there before Columbus arrived to be the region's indigenous plants.
Indigenous plants are sometimes allowed to co-exist with lawn grass, ground covers, or garden vegetables, especially if they are not aggressive growers. Indeed, some homeowners favor them, growing native specimens in their landscapes either as a matter of principle or for practical reasons, as when, for example, they are drought-resistant plants.
Some gardeners include indigenous plants in a woodland garden. And, because some types of wildflowers grow under the forest canopy in their natural habitats, they can be fitting candidates for shade gardens in your landscaping. Examples of indigenous plants for eastern North America that can be used in shade gardens include:
- Fringed bleeding heart (Dicentra eximia): zones 3 to 9
- Dutchman's breeches (Dicentra cucullaria): zones 3 to 7
- Jack-in-the-pulpit (Arisaema triphyllum): zones 4 to 9
- Bloodroot (Sanguinaria canadensis): zones 3 to 8
- Mayapple (Podophyllum peltatum): zones 3 to 8
- Bunchberry (Cornus canadensis): zones 2 to 7
- Woodland phlox (Phlox divaricata): zones 3 to 8
- Interrupted fern (Osmunda claytoniana): zones 3 to 8
- White baneberry (Actaea pachypoda): zones 3 to 8
While fringed bleeding heart and its Dicentra relative, Dutchman's breeches, are both indigenous to eastern North America, they have a more popular relative that is not: Common bleeding heart (Dicentra spectabilis) is indigenous to the Far East.
Other indigenous plants are valued for their suitability in gardens with partial sun or full sun in North America, such as:
- Goldenrod (Solidago): zones 2 to 8
- Blue flag (Iris versicolor): zones 3 to 9
- Joe-Pye weed (Eupatorium maculatum): zones 4 to 8
- Bee balm (Monarda didyma): zones 4 to 9
- Red columbine (Aquilegia canadensis): zones 3 to 9
- New England aster (Symphyotrichum novae-angliae): zones 4 to 8
- Black-eyed Susans (Rudbeckia hirta): zones 4 to 9
- Wild violets (Viola sororia): zones 3 to 9
- Purple pitcher plant (Sarracenia purpurea subsp. purpurea): zones 3 to 7
Wildflowers vs. Indigenous Plants, and Naturalized Weeds
Not all "wildflowers" commonly seen in a region are indigenous plants for that area, simply because they grow wild there. Lupine is a case in point. While there is a type of lupine (Lupinus perennis) that is indigenous to New England (United States), the showiest type of lupine (Lupinus polyphyllus) that grows wild there is not a native, but rather has been naturalized. Many wildflowers in your area may have been introduced from far-away lands and are therefore considered "alien" (which is the antonym for "indigenous"); some may even be invasive.
Another beautiful wildflower that North American plant lovers are often disappointed to learn is naturalized rather than indigenous is tiger lily (Lilium lancifolium), a native of the Far East. If they want to grow a native version, the closest thing to tiger lily is Turk's cap lily (Lilium superbum).
Money does not grow on trees, but it does grow on silver dollar plants (Lunaria annua), in the form of showy seed pods. This is another naturalized beauty that native-plant lovers are tempted to grow but often do not due to its tendency to spread.
Many more such cases of naturalized plants exist in the world of "weeds," which are defined as plants that the general public does not like (rather than being a distinct botanical group). One of the worst is Polygonum cuspidatum, indigenous to Japan and known commonly as "knotweed."
Often, a plant indigenous to one land, where it was used for centuries as food or as medicine, was brought to another as valued cargo, only to become a despised weed at a later age in history in its new land. Examples of weeds that have naturalized in North America are:
Indigenous Plants and Wildlife
One reason for the popularity of indigenous plants among some gardeners is their compatibility with wildlife. Two of the best examples in North America are butterfly magnets: