A new study suggests that having a variety of flowers that bloom throughout the season is more beneficial for bees and other pollinators than what is found around the flower garden.
Recent research published on September 4, 2024, in the open-access journal PLOS ONE by Devon Eldridge and colleagues from the University of Tennessee, shows that a rich and diverse flower garden may be more vital for bees and other pollinators than the surrounding environment.
With increasing awareness of the essential role pollinators, including both native and non-native bees, butterflies, and other insects, play in our food systems and ecosystems, many individuals are cultivating flower gardens that attract these important and vulnerable species. The research team led by Eldridge explored how the environment around these gardens (such as local context and broader land-use patterns) might influence the appeal of flower gardens to different bee species.
The researchers set up four types of gardens: three filled exclusively with plants from only one family (Asteraceae – daisies, Fabaceae – legumes, or Lamiaceae – mints) and one garden that mixed plants from all three families. These four garden types were replicated across five different sites that represented a mix of land uses, including urban gardens, forage grasslands, mixed agriculture, forests, and organic farms. From July 13 to August 17, 2020, they sampled bee species in these gardens and also conducted local surveys within a 50-meter radius of each garden on a weekly basis.
During their research, the team collected a total of 1,186 bees from 44 different species over 20.83 hours in the garden plots. In the surrounding areas, they identified 2,917 bees representing 52 different species over a total of 16.67 hours of surveying. The mixed agriculture site attracted the highest number of bees among the specific garden types, whereas the environment around the urban garden site yielded the greatest number of bees in the local area surveys. Intriguingly, the size of floral displays (the quantity of flowers on individual plants) and the diversity of flowers nearby did not significantly affect the number of bees or the variety of species found in the garden plots. Although there was a slight positive correlation between developed land use within a 2 km radius and bee abundance in the gardens, these effects were minimal. The most significant factors influencing the types and richness of bee species in the gardens were the size of floral displays and the variety of blooming plant species present.
Even though the authors mention that all the garden sites were situated within “patchy” and diverse landscapes, and that gardens next to areas with more intense or differing land uses might yield different findings, these results hint that landowners can enhance local pollinator populations by protecting existing natural areas and/or planting more flowering plants, particularly those that provide blooms across the entire season—regardless of the type of environment surrounding their gardens.
The authors conclude: “Many of us question how the area around our gardens impacts the pollinators that come to our flowers. Our research showed that the quantity and variety of flowers in the garden itself were more influential on pollinator numbers and diversity than the surrounding local or landscape context.”
