Mary Blickenderfer, Regional Extension Educator

Orders for native flowers, grasses, trees and shrubs are pouring into my local Soil and Water Conservation District for their spring plant sale…local shoreland property owners want to know how to collect seed and grow plants for their shoreland revegetation projects… schoolteachers are calling with questions on how to create native plant gardens for outdoor classrooms…several local business are attending the Lakescaping for Nursery and Landscape workshops coordinated by the Minnesota DNR… These recent events are evidence of the overwhelming interest in landscaping with native plants – especially for shoreland revegetation projects and water features – and the urgent need for information on how to use native plants successfully in the landscape.

Starting with this issue, Plant Topics will answer questions on why and how to use native seed and plants from local sources in shoreland landscaping. In this issue we will discuss what is a “native plant, “ and when and why we should use them. Upcoming issues will discuss native seed and plant sources, collection techniques and issues, amazing adaptations of native seeds and plants, cleaning and storing seed, propagating native plants from seed and cuttings, special propagation techniques for aquatic plants, and how to use and manage native plants in the landscape. Readers are encouraged to contact me with their native plant questions for inclusion in upcoming issues (Mary: 218-327-4616).

First of all, what is a “native plant?”

Using the broadest definition, every plant is native to the world! However, some plants are only found in very unique, local climate or soil conditions. Our working definition will fall somewhere in between. Nearly every native plant nursery and native plant restoration practitioner has their own working definition of what is native, usually measured in miles from a plant source. Agencies tend to use political (often state) boundaries. However, recent research indicates that the ecological classification system that divides Minnesota into three regions (see map) provides the best working definition. That is, native plant materials should be collected, propagated, and planted within a single ecological region.

Why shouldn’t we use plants from outside our ecological region?

The reasons are many. First, non-native plants may have no local “checks and balances,” in the form of insects and diseases, to control their population and may aggressively out-compete the native vegetation (Need I remind you of our constant battle with purple loosestrife, Eurasian water milfoil, curly-leaf pondweed, European buckthorn and honeysuckles – to name just a few?). Even plant cultivars bred from sources native to the Midwest may exhibit similar aggressive behavior (“Blackwell” switchgrass is one to avoid.). As many know, non-native plants may not survive our harsh northern climate (How many dollars are wasted on water plants ordered from southern sources or “meadow-in-a-can” mixes from California sold in local department stores?). Alternatively, plants from outside an ecological region may survive within a region but not be able to reproduce under local climate or soil conditions. Finally, there is a growing body of research indicating that non-native plants provide inadequate habitat for the local wildlife, in many cases threatening their survival.

When are non-native plants appropriate in the landscape?

Non-native plants and cultivars provide welcome additions of color, texture, and form to a landscaper’s pallet. They can be used most effectively in plantings close to dwellings, offices, or other public areas where they can be readily viewed, enjoyed, and maintained. Use of non-natives in water features (man-made ponds or water gardens) or in close proximity to public waters is discouraged in an attempt to prevent another “purple loosestrife event.” It is important to note that planting non-natives in public waters (below the Ordinary High Water Level) is prohibited for the same reason.

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