University of Minnesota Extension Master Gardeners Win International Award

Jake Miller
Newsletter Issue: 
June 2015

This September, Extension Master Gardeners from the University of Minnesota and Iowa State University will be honored for their research on biochar as a soil additive, at the International Master Gardener Conference. The Search for Excellence award is being given for research conducted by CenUSA Bioenergy sponsored volunteers.  Two of the University of Minnesota Master Gardeners, Dave Knapp and Sandra Shill, authored the proposal submitted to the International Master Gardener committee. Master Gardeners are volunteers educated by land-grant universities dedicated to life-long learning and educating the public about best practices in horticulture using research-based information.

“We were the vehicles by which the application was submitted,” said Knapp, who has been an Extension Master Gardener in Anoka County, Minnesota, for eight years now. Knapp first began volunteering with the program when he retired and has recently finished a three-year term on the Minnesota State Master Gardener Advisory Board. Knapp is active with many other facets in the program including the “Ask A Master Gardener” booths. These booths, designed to put the program in the public eye, are set up at fairs or gardening centers across the state to help answer people’s home gardening questions. The booths also display a small-scale version of the biochar experiment and information explaining the potential benefits of biochar for home gardens.

“The United States, Canada and South Korea are all represented at this conference,” said Theresa James, International Master Gardener Committee chair. “There are around 50 teams competing in each of the seven categories.”  The CenUSA biochar project was selected as the winner in the research category.

The CenUSA project is funded by the USDA National Institute for Food and Agriculture and has two prongs of research; university sanctioned and citizen scientists. “The Extension Master Gardeners are citizen scientists because they conduct research and try to answer an experimental question but they don’t operate within the typical university academic setting,” said Anne Kinzel, chief operation officer at CenUSA. The Master Gardeners were sought out by CenUSA to help research the use of biochar in home gardens.

The biochar demonstration gardens are replicated at four sites in Minnesota and three sites in Iowa.  The Master Gardeners observe vegetables, annual flowers, shrub roses and asparagus grown in soil amended with hardwood biochar contributed by Royal Oak Industries. Each 1000 square foot demonstration garden consists of a control plot (no biochar applied), treatment 1 (one-half pound of biochar per square foot), and treatment 2 (one pound of biochar per square foot). The biochar was applied only the first year of the study and fertilizer is applied to each site per soil test recommendations annually. Each site differs by soil type (silt loam, sandy soil and heavy clay). The volunteer researchers plant and maintain the sites in teams and record observed differences in crop performance with the goal of determining whether biochar makes a difference on plant growth when applied on different types of soil. Lynne Hagen, University of Minnesota Extension Master Gardener Program Coordinator for Anoka County and project manager for this research project explained the research results are still being compiled.

“There is still a lot to learn,” said Hagen. “The results we’ve seen so far haven’t shown any huge patterns yet that would convince us that biochar is a viable option in home gardens, especially in terms of growth and yield. However, there have been subtle differences noticed in poor quality soils with some plants and it has been helpful in reducing compaction.” Most notably, volunteers have reported soils amended with biochar are lighter and do not require tilling each year. Soil samples have also been submitted and tested for differences in water-holding capacity to test the hypothesis that biochar improves the water and nutrient-holding capacity in poor soils.

The award will be presented at the International Master Gardener Conference to be held September 22 to the 25th in Council Bluffs, Iowa. Further information about this research can be found at the CenUSA website, cenusa.iastate.ed or at the eXtension blogsite:

Volunteers measuring plant growth in garden
Two volunteers measuring a plant grown in biochar soil for their date 
requirements on the St. Paul Campus site.

Volunteers Dave Knapp and Mary Fitch
Two volunteers in the Master Gardener program, 
Dave Knapp and Mary Fitch, check in on a tomato 
plant grown in biochar soil. Knapp and Fitch
volunteer at the site in Andover, MN.