The Blue Thumb Plant Finder is a tool to help people find Minnesota native plants that will thrive where they’re planted. It is composed of plants that are generally commercially available, and can be used to create planting plans for all types of projects.
The state of Minnesota does have a group of seed mixes to be used in stormwater projects as part of a seed mix finder tool for other types of projects.
| Plant Type | Forbs are usually considered “wildflowers,” with non-woody stems that die back to ground level after the growing season. Grasses includes true grasses as well as graminoids like sedges and rushes. Ferns are woodland plants most notable for their intricate foliage. Shrubs are woody-stemmed plants, often multi-stemmed, that aren’t as tall as Trees. |
| Height | Height of the plant at maturity. Arranging plants by height can be a great way of adding layers and visual complexity to your project. There are situations where you should avoid taller plants—for example, many municipalities regulate the maximum height of plantings within boulevards or near street corners to maximize sight-lines for drivers. |
| Light Exposure | Generally, a site has Sunny conditions if it receives 6 or more hours of direct sunlight a day during the growing season. Shade is usually less than 3 hours of direct sunlight. Part Sun is between 3 and 6 hours. Note that direct sunlight in the afternoon/evening is more intense than in the morning (i.e. shade plants that receive a couple hours of morning light will probably do better than shade plants receiving a couple hours of light later in the day). |
| Soil Moisture | Generally, Dry soil is composed mainly of sand, gravel, and or rocks and never has standing water. Medium soil has more organic matter and/or clay, and drains within a day or two of soaking rain. Wet soil is often saturated, does not drain well, and can be quite clay-heavy. |
| Bloom Color | Bloom color refers to the color of the flowering part of the plant. |
| General Resilience | This is a 1-10 score assigned to each species based on their ability to withstand stressors and persist over time within an urban planting with an emphasis on urban stormwater and upland buffer plantings. Stressors that may impact plant species may include climate change impacts from drought, flooding or water level fluctuations; or other environmental stressors such as plant diseases, sedimentation, herbivory, competition from other native plants, and pressure from invasive plant, animal or insect species. The score is based on an assumption that plant species are installed within suitable growing conditions such as a woodland plant being planted in shade and suitable moisture levels. This score can be used to determine which species may be most successful over many years in an urban planting. |
| Ecoregion | Minnesota is divided into 7 Ecoregions by the EPA. Learn more and determine your Ecoregion here. If you find your location is on the edge between two, consider which type of landscape you are trying to create (i.e. woodlands or prairie). |
| Bloom Months |
Refers to the months of the year in which the plant is flowering/in bloom. This varies based on location (a plant in Rochester may bloom weeks earlier than the same plant in Ely). |
| Larval Host of | Indicates if a plant is known to host the eggs and larvae of Bees, Butterflies, or Moths. |
| Pollinator Benefit | Indicates the types of benefits the plant gives pollinators, including pollen (if it is Insect Pollinated), which is full of protein and fed to bee larvae to help them grow into adults; if it Provides Nectar, which is what adult pollinators rely on for sustenance; if it provides opportunity for Stem Nesting bees, which seek out hollow-stems; if it is known to Support Generalists (pollinators that feed on a variety of flowers through the year); and/or if it Supports Specialists (i.e. some bees whose whole life-cycles are scheduled around the blooming of a specific flower species, which they rely on for nutrition). |
| Pollinator Value | Indicates the degree to which it is known that native pollinators rely on the plant for food or shelter. |
| Specific Pollinators Hosted |
Known pollinator larvae hosted by each plant; in cases of plants hosting more than 3 species of Bees, Butterflies, or Moths, instead of a list it will say “Numerous…species”. This is not a searchable term, it is just information on individual plant pages. |
| Project Type | Project Type refers to the suitability of a plant for involvement in projects that improve water quality. Project Types in Plant Finder include Raingardens, Restoration, Bee Lawn, Erosion Control, Shoreline Buffer, Upland Buffer, Boulevard, and Sandy or Engineered Soils. For more information about these projects, explore our planning resources or refer to the Minnesota Stormwater Manual. |
| Coefficient of Conservatism | Also known as C-values, this is a numerical rating (0–10) of a species’ fidelity to specific habitats and tolerance of disturbance. Species with narrow habitat requirements and little tolerance to disturbance have high C-values and vice versa. Projects in disturbed soil exposed to many stressors (especially artificial ones) and without a lot of ongoing maintenance may not be the most inviting site for a high C-value plant. |
| Flooding/Inundation Tolerance | Plants are most tolerant of prolonged inundation early in the growing season when they are still dormant, and are most susceptible when they are actively growing; this timing can vary for plant species. Most plants are also susceptible to loss if the plant is totally inundated under the surface of the water.
Low: Withstands inundation of up to 6-inches of water in a stormwater practice or shoreline for about 12 hours, and has a low tolerance of water fluctuations Moderate: Withstands inundation of up to 12-inches of water in a stormwater practice or shoreline for about 24 hours, and has a moderate tolerance of water fluctuations High: Withstands inundation of up to 18-inches of water in a stormwater practice or shoreline for about 36 hours, and has a relatively high tolerance of water fluctuations Very High: Withstands inundation of 24-36 inches of water in a stormwater practice or shoreline for 48 hours or longer, and has a high tolerance of water fluctuations |
| Herbivore Sensitivity | Indicates how susceptible the plant is to grazing and foraging by deer, rabbits, or other wildlife. |
| Rate of Spread | Plants with a Slow rate of spread tend to stay in place. A Fast rate of spread can even be aggressive and overtake plants that aren’t as well-suited to the site conditions, or that are just much slower-growing. |
| Salt Tolerance | Salt tolerance refers to how well a plant is able to withstand (without significant adverse effects) exposure to salt on its leaves or in the soil within reach of its roots. |
| Stress Tolerance | Indicates other difficult or extreme conditions the plant might tolerate. Note that many plants are much better able to tolerate stresses once established; Drought Tolerant plants, for instance, still might need supplemental watering during their first couple years to help them grow the roots they need to make it through drier seasons. |
| Soil Stabilization | Plants were determined to have dominantly Shallow or Deep root systems if the majority of their roots were less or more than a foot deep. Shallow-rooted plants may be better suited to resist surface erosion, and deep-rooted plants may be more helpful along banks and slopes to help prevent slopes from collapsing or failing when inundated or under load. |
| Approximate Eco Province | The 4 Minnesota DNR Ecological Province boundaries are roughly overlapped by the 7 EPA Ecoregion boundaries, so Eco Provinces have been roughly assigned to each plant according to their native Ecoregion(s). Note that the Tallgrass Aspen Parklands and far NW MN had the widest variance between Ecoregion and Eco Province; we recommend referring to Ecoregions in those cases. |
| Documented in County | The Minnesota counties in which the plant has been documented as “native” according to MNTaxa. Some plants may be native in counties that are not listed; we recommend also using the Ecoregion (in the Basic Search Filter) of your project to draw plant options from. |
| Lifespan | Annual plants sprout, set seed, and die in one year. Perennial plants may take longer to bloom and set seed, and live for many years. Biennial plants have a 2-year lifecycle. |
| Vegetative Reproduction | Many plants display Clonal reproduction, being able to spread through their roots, rhizomes, stolons, or stems. These plants tend to grow in clumps. Plants with Absent vegetative reproduction must spread through seed. |
This project was supported by the University of Minnesota Water Resources Center through an appropriation from the Clean Water Fund established by Minnesota Clean Water Land and Legacy Amendment and from the Minnesota Stormwater Research Council with financial contributions from:
For more information about the Center and the Council, visit https://www.wrc.umn.edu/projects/storm-waste-water
For more information about the Minnesota Clean Water, Land and Legacy Amendment, visit https://www.legacy.mn.gov/about-funds
Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the Water Resources Center or the Minnesota Stormwater Research Council.
Photos were provided by many people and organizations, including Minnesota Wildflowers, MNL, Ecoscapes, and Light Dark Landscape. Some photos are from the USDA Plants Database.
Information was collected or supplied from many sources, including:
Plants for Stormwater Design: Species Selection for the Upper Midwest, a guidebook created by Dan Shaw and Rusty Schmidt. Much of it is available as a pdf on the Minnesota Stormwater Manual.
Minnesota Department of Natural Resources Minnesota Biological Survey with funding from the Environment & Natural Resources Trust Fund. The State of Minnesota and DNR hold a copyright to the pollinator information provided.
USDA PLANTS Database: USDA, NRCS. 2024. The PLANTS Database (http://plants.usda.gov, 05/28/2024). National Plant Data Team, Greensboro, NC USA.
USFHA Ecoregional Revegetation Application: United States Department of Agriculture and US Federal Highway Administration. 2017. National database for pollinator-friendly revegetation and restoration. Compiled by Mark W. Skinner, Gretchen LeBuhn, David Inouye, Terry Griswold, and Jennifer Hopwood. Online at http://www.nativerevegetation.org/era/. Contact Mark W. Skinner (mskinner02@fs.fed.us or mwskinner55@gmail.com) for updates or more information.
