Native Plants in Gardens & Landscapes

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Advantages of Native Plants for Biodiversity

Native plants offer a large potential for maintaining biodiversity globally. As commercially available non-native plants are cultivated through cloning, artificial selection, and distributed internationally, the native biodiversity that they displace is lost. Many native species are threatened by habitat loss and fragmentation due to development, where they are unable to reestablish populations due to the reduced amount of habitable area and displacement by the intentional planting of non-native plants.


Turfgrass covers 163,812 km² in the United States, an area three times larger than any irrigated crop[1]. This displaces a vast amount of native vegetation and diverse habitat. A cultivated, intentionally monoculture lawn promotes the removal of non-target species with the use of herbicides and pesticides, intensive irrigation to sustain the lawn in dry times, and fertilizers to promote growth[2]. Commonly used glyphosate herbicides used to maintain non-native lawns have been shown to be harmful to aquatic invertebrates and fishes[3].


Native plants support biodiversity not only through the presence of their own species but through the ecosystem foundations they provide. As native plants co-evolved within the same geographic ranges, they specialize in a variety of ecological niches[4] spatially, temporally, and in resource use. Pollinator alliances[5] and herbivore interactions[6] can drive speciation and divergence, and increase the local interconnectivity of native ecological communities.  

The dimensional depth added with a variety of native plants increases the opportunity for resource partitioning and niche diversification[7], where animals are able to utilize multiple areas of a plant vertically. Razed lawns or hedged ornamental species do not offer this habitat complexity and reduce the potential for animal diversity.


Non-native drought tolerant, erosion control, and ornamental plants can become invasive to adjacent wild areas and aggressively outcompete natives, lowering overall biodiversity by altering species composition and causing local extinction.

Pollinator Benefits

A pollinator is an animal that facilitates the transfer of pollen between individual plants. Many pollinator life cycles, behaviors, distributions and morphology, coevolve with those of plants. Common pollinators include moths, butterflies, birds, bats, beetles, and ants.


Flower morphology often reflects the pollinators that visit them. Some native plant species pollinated by hummingbirds and moths have coevolved elongated flowers[5] that are only accessible by the long tongue or proboscis of their complementary pollinators. Native plants with poricidal anthers require pollen be knocked loose in a process called buzz pollination, which is done by North American native bumble bee species & cannot be done by introduced European honeybees[8] . European honeybees are also less efficient pollinators[9] compared with many North American native bee species, such as solitary bees and bumblebees.


Pollinators such as beetles, ants, nocturnal moths, and bats are often overlooked but are also vital to the diversity of our ecosystems. Some cactus species have specially adapted flowers that can be located with echolocation[10] and are pollinated nocturnally by bats. Flower characteristics including colors, scents, and bloom times are also often correlated with attracting specific native pollinators.


As adults, butterflies and moths often feed as generalists, visiting a wide variety of native and non-native flowering plants. However in larval stages, they commonly specialize on particular native host plant families or genera[11], and require access to these plants to successfully reproduce and sustain their populations.  Ornamental and weedy non-native plants can be toxic to the larvae of native insect pollinators or not recognized as a food source, potentially reducing insect diversity[11].

Having native plants alongside edible plants can increase pollination and crop yield, and is being utilized in agricultural settings[12] to supplement pollination by introduced beehives.

Mitigation of Climate Change with Native Plants

Native plants do not require as frequent machine maintenance as turfgrass lawns, which are often mowed 2-4 times a month[13]. This process disrupts and removes animal habitat, and can directly harm plants and animals. Mowers often injure small wildlife[14] and loud blowers, mowers, and trimmers scare off wildlife[15], interrupt foraging, and produce significant noise and air pollution[16].

Native plants promote healthy soil through their roots and through plant material that decomposes into humus. Soils are a significant component of carbon sequestration, and represent the largest terrestrial carbon storage pool[17].

Stormwater and Runoff Management with Native Plants

The large-scale removal of native planted habitat and subsequent conversion to paved and impermeable surfaces has caused a major increase in urban runoff. The Environmental Protection Agency (EPA) estimates that because of impervious surfaces such as pavement and rooftops, a typical city block generates five times more runoff than a woodland area of the same size, while only about 15% infiltrates into the ground for groundwater recharge instead of 50% infiltration[18]. Native plants provide increased surface area for rain interception on leaves, stems, and trunks of plants, slowing the descent of rainwater.


Non-native grasses often have shorter, less robust root systems and store less carbon than native grasses[19]. The extensive root systems of native plants promote biologically active soils with spaces for micro and macro organisms that act as a sponge for rainwater. Compacted, inactive soils act hydrophobically, increasing runoff volume. In an experiment comparing runoff capture with native vs. non-native grasses, native grasses attenuated 41% of runoff compared to 27% of runoff in a non-native turf grass swale[20].

a diagram with several plants in a line, showing above and below ground growth. The turfgrass is much shorter in both aspects compared to the native prairie plants.
Diagram of the root systems of native prairie plants compared with the short roots of turf grass on the left. © 2012 Nature Education 1995 Conservation Research Institute, Heidi Natura

Suitability for Regional Climates and Resources

Soil conditions within a region may be inhabitable for most commercially grown non-native plants. Salty soils, anoxic soils, and nutrient poor soils often are not suitable for introduced plants, which are commonly selected for aesthetic preference over specialized adaptive tolerance. Regionally adapted native plants, evolved to tolerate specific challenging conditions, can show greater fitness than non-native alternatives, and require less supplemental alterations in the form of amendment soils, filling an area with imported soils, and chemical fertilizers.


Native plants are similarly better adapted to local climate extremes than the majority of their non-native counterparts, and will tolerate drought, seasonal flooding, frosts, fires, depending on their regional pressures.


In dry climates, native plants require less supplemental irrigation, conserving water and preventing dry weather runoff. Native plants can also have more robust and extensive root systems to access and retain groundwater, especially compared to turfgrass. These larger root systems have added benefits of preventing soil erosion and more area for associated microorganism activity and diversity.


Non-native plants such as grasses and palms may be drought-tolerant, but can pose fire risks to their introduced area and alter natural succession patterns following fire events[21].


Plant phenologies also vary regionally. Native plants may be adapted to bloom during seasons that align with rainfall patterns, local climate, or coevolution with pollinators. Native plants have adapted to succeed with available local resources and alongside other native plants and animals in highly interconnected ways.

Additional Local Fauna Benefits

Seeds and fruits produced by native plants provide food for birds, mammals, and insects. As photosynthetic organisms, native plants create the foundation of the food chain and indirectly and directly provide food for local fauna. Plants that support native insects provide a food source for insect eating birds, reptiles, and amphibians.


Native plants provide shelter and materials for beneficial insects, birds, reptiles, amphibians, mammals, and pollinators. Many bird species of conservation concern only nest in one plant or plant community, and have specific requirements for nesting materials.

Additional Human Benefits

Native plants can counteract urban heat island effects[22] through evapotranspiration, shading, and having lower thermal conductivity compared to artificial materials like pavements and buildings.


Native plants can act as human food sources that are regionally adapted, requiring less supplemental irrigation and inputs of fertilizers. Traditional ecological knowledge of native plant uses, including edible and medicinal uses, can be perpetuated and preserved through planting and interaction with native plants.


Many native plants have become culturally important symbols within their regions. Iconic and charismatic plant species can drive tourism and promote conservation efforts[23]. Increasing the accessibility and availability to connect with nature through native plants provides a unique value to communities, especially in urban areas lacking green space. Increased familiarity with native plants and their benefits can provide motivation for protection and stewardship of their habitats and continued existence.

Challenges in landscaping with native plants

The commercial availability of native plants can pose a challenge for those who wish to landscape with them. Many large scale home improvement stores do not carry a large selection of regionally native plants for purchase. Nurseries that specialize in native plants can be located out of range that a gardener is willing or able to travel, and some nurseries may only sell in wholesale quantities. Local nature conservancies and native plant groups may have plants available for purchase at yearly sales, but few have the staffing and facilities to grow, maintain, and sell stocks of native plants year round.


Commercially available pollinator plants, such as milkweed, may be exposed to pesticides during cultivation. A study on milkweed in California showed widespread pesticide contamination of plants in urban wildlife refuges, adjacent to farms, and available for purchase by home gardeners, even when the landowners avoided pesticide use[24]. More research is needed on the severity of the effects of these pesticides and the sources of contamination, but it is likely these chemicals endanger the offspring of butterflies using these plants for their larvae.


For homeowners, social pressure[25] or a fear of standing out from neighbors’ yards may factor into native plant landscaping. Homeowners associations may present obstacles to implementing non-grass or non-traditional landscaping with native plants. A Maryland couple faced this problem when their neighbor complained about the native plants in their yard, resulting in their HOA ordering them to remove their native plants and install a turf lawn. The homeowners lawsuit to keep their native plants formed the basis of a new Maryland state law HB322, passed in October 2021, which protects low impact landscaping, rain gardens, pollinator gardens, and other habitat gardens[26].


Native plants are often unfamiliar to gardeners working with conventional imported landscaping plants, and there may be limited information available on how to take care of native plants in a landscape setting. Improper maintenance by both professionals and hobbyists can present problems for plant survival. In dry areas, gardeners may overwater native plants if they are accustomed to thirsty, maladapted non-natives, or apply fertilizers to plants that thrive in poor soils and cannot process excess nutrients. As previously mentioned, native plants may be difficult to purchase, further adding to frustration and disappointment when plants do not survive.


Well intending gardeners may plant native plants that are regionally maladapted or in an ill-suited area of their yard, only to watch the native plant struggle or die. For example, planting a redwood tree in San Diego, a desert cactus under a shady tree, or a fern in full sun, will likely result in a plant that does not thrive. A plant may be native to a state or county, but in a different set of climate conditions or resources than what is available in your immediate area.

Solutions

There is a need to increase the availability and accessibility of native plants for purchase and use by the general public. It is important to leverage established horticulturists, plant nurseries, and retailers to diversify the amount and variety of native species offered. Another option is to support or volunteer for organizations and conservancies that host native plant sales or distribution events. Learn to propagate and grow native plants in your backyard, and collect and share seeds of native plants that are in landscaping settings.


Another important solution will be increasing availability and accessibility of information about native plants and their benefits to the public. It is crucial that we protect and conserve remaining wild areas that showcase native plant diversity and can be used to produce locally adapted “mother” plants for nurseries and widespread distribution. When implementing gardens in urban areas that feature native plants, it is important to prioritize public accessibility to create gardens that foster inclusive appreciation for native plants and their diversity.


Neighboring wild areas can be protected by removing invasive species from existing landscaping and not purchasing invasive plants. We can also inform plant retailers and landscapers of plants to avoid depending on the region.


Working with Homeowners Associations (HOAs) and property management groups that do not support native plants in landscape will help reduce barriers for planting native species. By creating state laws that protect property owners, such as the state of Maryland's law HB322[26], low-impact & wildlife supporting landscapes can become a widespread solution to habitat loss and stormwater pollution.


The Surfrider Foundation’s Ocean Friendly Gardens Program increases awareness of the benefits of native plants and promotes the use of at least 50% regionally native plants within certified gardens. Native plants are strongly recommended whenever possible. The program works to establish demonstration gardens, educate volunteers and the public, and inspire people to take action in their yards. The program aims to combat the pollution of beaches, oceans, and waterways by urban runoff and stormwater through the use of sustainable landscaping practices and water capture strategies.

Native Plant Resources for Gardeners

United States (National Resources)

Audubon Native Plants for Birds Database

uses zipcode to recommend native plants with a focus on improving habitat & resources for bird conservation

Xerces Society Native Plants for Pollinators

regionally curated native plant lists with a focus on improving habitat & resources for invertebrate conservation (with an emphasis on pollinating insects)

Ladybird Johnson Wildflower Center Native Plant Database

Find a Native Plant Society in Your State

Resources by U.S. State

California

  • Bloom! California
    • introduction to California native plants popular in landscaping, includes a nursery locator
  • Calscape
    • useful resource for investigating potential species to add to your garden, includes detailed information & nursery locator
  • California Native Plant Society
    • a way to learn about plants native to California and connect with others who are passionate about conservation & gardening with native plants
  • Theodore Payne Foundation for Wild Flowers & Native Plants
    • offer classes, workshops, a certification program for landscapers, and sell seeds and plants through their nursery
  • Land Resilience Partnership Climate Appropriate Plantings Toolkit
    • plant list and planting information for coastal areas with cool summers and inland valleys with hot summers
  • The Butterfly Net (beta)
    • A conservation tool that shows priority plant species in your area of California to support moths and butterflies. Includes great visual representations of the interconnectivity of native plants and native pollinators, with links to information about both.

Florida

New York

  1. ↑ Milesi, C., Elvidge, C.D., Dietz, J.B., Tuttle, B.T., Nemani, R.R. and Running, S.W., 2005. A strategy for mapping and modeling the ecological effects of US lawns. J. Turfgrass Manage, 1(1), pp.83-97.
  2. ↑ Cook, E. M., Hall, S. J., & Larson, K. L. (2012). Residential landscapes as social-ecological systems: A synthesis of multi-scalar interactions between people and their home environment. Urban Ecosystems, 15(1), 19–52.
  3. ↑ Folmar, L.C., Sanders, H.O. and Julin, A.M., 1979. Toxicity of the herbicide glyphosate and several of its formulations to fish and aquatic invertebrates. Archives of Environmental Contamination and Toxicology, 8(3), pp.269-278.
  4. ↑ Silvertown, J., 2004. Plant coexistence and the niche. Trends in Ecology & Evolution, 19(11), pp.605-611.
  5. ↑ 5.0 5.1 Whittall, J.B. and Hodges, S.A., 2007. Pollinator shifts drive increasingly long nectar spurs in columbine flowers. Nature, 447(7145), pp.706-709.
  6. ↑ Gloss, A.D., Dittrich, A.C.N., Goldman-Huertas, B. and Whiteman, N.K., 2013. Maintenance of genetic diversity through plant–herbivore interactions. Current Opinion in Plant Biology, 16(4), pp.443-450.
  7. ↑ MacArthur, R.H., 1958. Population ecology of some warblers of northeastern coniferous forests. Ecology, 39(4), pp.599-619.
  8. ↑ De Luca, P.A. and Vallejo-Marin, M., 2013. What's the ‘buzz’ about? The ecology and evolutionary significance of buzz-pollination. Current opinion in plant biology, 16(4), pp.429-435.
  9. ↑ Woodcock, B.A., Edwards, M., Redhead, J., Meek, W.R., Nuttall, P., Falk, S., Nowakowski, M. and Pywell, R.F., 2013. Crop flower visitation by honeybees, bumblebees and solitary bees: Behavioural differences and diversity responses to landscape. Agriculture, Ecosystems & Environment, 171, pp.1-8.
  10. ↑ von Helversen, D. and von Helversen, O., 1999. Acoustic guide in bat-pollinated flower. Nature, 398(6730), pp.759-760.
  11. ↑ 11.0 11.1 Graves, S.D. and Shapiro, A.M., 2003. Exotics as host plants of the California butterfly fauna. Biological conservation, 110(3), pp.413-433.
  12. ↑ Wratten, S.D., Gillespie, M., Decourtye, A., Mader, E. and Desneux, N., 2012. Pollinator habitat enhancement: benefits to other ecosystem services. Agriculture, Ecosystems & Environment, 159, pp.112-122.
  13. ↑ Robbins, P., 2012. Lawn people: How grasses, weeds, and chemicals make us who we are. Temple University Press.
  14. ↑ Hartup, B.K., 1996. Rehabilitation of native reptiles and amphibians in DuPage County, Illinois. Journal of Wildlife Diseases, 32(1), pp.109-112.
  15. ↑ Burger, J., 1981. The effect of human activity on birds at a coastal bay. Biological conservation, 21(3), pp.231-241.
  16. ↑ Banks, J.L. and McConnell, R., 2015, April. National emissions from lawn and garden equipment. In International Emissions Inventory Conference, San Diego, April (Vol. 16).
  17. ↑ Scharlemann, J.P., Tanner, E.V., Hiederer, R. and Kapos, V., 2014. Global soil carbon: understanding and managing the largest terrestrial carbon pool. Carbon Management, 5(1), pp.81-91.
  18. ↑ Copeland, C., 2016. Green Infrastructure and issues in managing urban stormwater.
  19. ↑ Koteen, L.E., Baldocchi, D.D. and Harte, J., 2011. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands. Environmental Research Letters, 6(4), p.044001.
  20. ↑ Liptan, T. and Murase, R.K., 2002. Watergardens as stormwater infrastructure in Portland, Oregon. Handbook of water sensitive planning and design, pp.125-154.
  21. ↑ Lambert, A.M., D’antonio, C.M. and Dudley, T.L., 2010. Invasive species and fire in California ecosystems. Fremontia, 38(2), pp.29-36.
  22. ↑ Tan, J.K., Belcher, R.N., Tan, H.T., Menz, S. and Schroepfer, T., 2021. The urban heat island mitigation potential of vegetation depends on local surface type and shade. Urban Forestry & Urban Greening, 62, p.127128.
  23. ↑ Hall, C.M., James, M. and Baird, T., 2011. Forests and trees as charismatic mega-flora: implications for heritage tourism and conservation. Journal of heritage tourism, 6(4), pp.309-323.
  24. ↑ Halsch, C.A., Code, A., Hoyle, S.M., Fordyce, J.A., Baert, N. and Forister, M.L., 2020. Pesticide contamination of milkweeds across the agricultural, urban, and open spaces of low-elevation northern California. Frontiers in Ecology and Evolution, 8, p.162.
  25. ↑ Cook, E. M., Hall, S. J., & Larson, K. L. (2012). Residential landscapes as social-ecological systems: A synthesis of multi-scalar interactions between people and their home environment. Urban Ecosystems, 15(1), 19–52.
  26. ↑ 26.0 26.1 Maryland House Bill 322 - Real Property - Restrictions on Use - Low-Impact Landscaping
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