Flower strips and buffer zones have the potential to counteract societal challenges mainly related to biodiversity enhancement and water management in the following ways:

Farmers usually implement these NbS themselves as it includes sowing or planting a strip or zone of some mixtures of plants in, or along the border of, a cultivation or along a water course. Alternatively, they can leave a field strip out of production and let it develop with grass and herbs. The flower strip does not have to be implemented along a field border but can be localized in a suitable area on the farm. Sometimes the buffer zone can also be used for production of biomass, and hence contribute to economic value and offset some or all of the cost of implementing it. 

In urban areas the implementation of flower strips is similar and can be done by the municipality or private property owners in parks and gardens to increase flower richness.

Flower strips can benefit insects and spiders in terms of providing food in resource scarce landscapes. Some studies also show positive effects on birds. Both pollination and pest control can potentially increase by implementing flower strips. 

Buffer zones can protect against nutrient leaches and eutrophication of water, but also benefit invertebrates such as beetles. As the soil is bound by the vegetation, it will prevent erosion and on slopes it can sometimes prevent soil from running off the field. It can also increase recreational values through serving as walking strips in the landscape. 

This NbS needs some arable land or other land where it can be implemented and sometimes this requires that productive land is taken out of production. To make any noticeable effect for the insect population in the long term, the flower strips probably need to be of a substantial area.

Flower strips are often made of annual flowers, which means new strips must be resown every year to maintain high flower abundance. The successful use of buffer zones to reduce field run-off may require considerable set-asides to cover stream- and catchment areas. Therefore, buffer zones are perhaps best used for multiple purposes. For example, buffer zones, especially those dominated by grass, could be used for recreation. However, as citizens are not usually legally allowed to enter farmland, there must be some arrangement between the farmer and the community/municipality for such activities to take place.  

If the NbS is implemented in an urban setting, available seed mixtures often include exotic species, which may have lower potential for benefiting biodiversity and especially rare specialist species as compared to native plant species.  

How much do we know?

Flower strips and buffer zones are relatively well researched. However, many studies compare short-term and direct effects of the strip itself, and few show effects on landscape and population scale in the long term. There is low confidence and varied results about the effects on crop yield. There are also research gaps when it comes to the social viewpoint. 

Costs

The cost will vary depending on the value of the land where the NbS is implemented. There is a cost of establishing flower strips and buffer zones, and the maintenance costs depend on the aim of the strip or zone. Flower strips might need to be resown each year. 

Albrecht, Matthias, David Kleijn, Neal M. Williams, Matthias Tschumi, Brett R. Blaauw, Riccardo Bommarco, Alistair J. Campbell, et al. 2020. “The Effectiveness of Flower Strips and Hedgerows on Pest Control, Pollination Services and Crop Yield: A Quantitative Synthesis.” Ecology Letters 23 (10): 1488–98. doi:10.1111/ele.13576. 

Burn, Alastair. 2003. “Pesticide Buffer Zones for the Protection of Wildlife.” Pest Management Science 59 (5): 583–90. doi:10.1002/ps.698. 

Christen, Benjamin, and Tommy Dalgaard. 2013. “Buffers for Biomass Production in Temperate European Agriculture: A Review and Synthesis on Function, Ecosystem Services and Implementation.” Biomass and Bioenergy 55 (August): 53–67. doi:10.1016/j.biombioe.2012.09.053. 

Haenke, Sebastian, Barbara Scheid, Matthias Schaefer, Teja Tscharntke, and Carsten Thies. 2009. “Increasing Syrphid Fly Diversity and Density in Sown Flower Strips Within Simple Vs. Complex Landscapes.” Journal of Applied Ecology 46 (5): 1106–14. doi:10.1111/j.1365-2664.2009.01685.x. 

Herbertsson, Lina, Annelie M. Jönsson, Georg K. S. Andersson, Kathrin Seibel, Maj Rundlöf, Johan Ekroos, Martin Stjernman, Ola Olsson, and Henrik G. Smith. 2018. “The Impact of Sown Flower Strips on Plant Reproductive Success in Southern Sweden Varies with Landscape Context.” Agriculture, Ecosystems & Environment 259 (May): 127–34. doi:10.1016/j.agee.2018.03.006. 

Jönsson, Annelie M., Johan Ekroos, Juliana Dänhardt, Georg K S Andersson, Ola Olsson, and Henrik G. Smith. 2015. “Sown Flower Strips in Southern Sweden Increase Abundances of Wild Bees and Hoverflies in the Wider Landscape.” Biological Conservation 184: 51–58. doi:10.1016/j.biocon.2014.12.027. 

Norris, Vol. 1993. “The Use of Buffer Zones to Protect Water Quality: A Review.” Water Resources Management 7 (4): 257–72. doi:10.1007/BF00872284.