The Garden Decoder: What Are ‘Native Plants’?

Last month, I wrote about “organic gardening” and what that really entails. A term that kept popping up while reporting that column: “native plants.” What are they, how are they important, and why are civilians across the country volunteering to rip non-natives from our landscapes?

What are native plants?

They are plants indigenous to a specific ecoregion, which is characterized by shared climate, soil conditions, and fauna. It’s a relative term: A plant may be native to one part of your state but not another. The one fixed criteria is that native plants grow naturally, without human intervention, in that specified ecoregion.

Why are they important?

Native plants are favorites among organic gardeners because they contribute to a balanced ecosystem. They provide sustenance and shelter to insects, birds, and other wildlife in a specific area, they are able to thrive in that region’s climate and soil conditions without much human intervention or extra resources (such as water, fertilizer, pesticides), and they encourage biodiversity. For instance, research by entomologist Doug Tallamy shows that native oak trees host more than 500 species of caterpillars while ginkgos, which are native to Asia, host only 5 species of caterpillars in the same region.

Are all non-native plants bad?

Also known as “alien plants,” non-native plants outnumber native plants in most nurseries, and chances are, your garden has some, if not a lot of, non-natives. The good news: They’re not all equally bad. Some non-natives may not add to biodiversity, but they do naturally thrive in the climate and soil conditions of their adopted home and won’t be a drain on natural resources. The real problem arises when the non-native plant is also invasive. Invasive plants are non-natives that aggressively spread at the expense of other plants. (See some common invasive species in Native Plants: 10 Alternatives to Invasive Garden Invaders.)

For more on native plants, see:

• Pollinator Gardens: 8 Easy Steps to Design a Landscape with Native Plants
• Native Perennials for a Shade Garden: 9 Favorites for Cold Climates
• Wild Flower Society: 10 Outside-the-Box Native Plants