Master Gardener and Youth Programs

Extension Master Gardeners

Is biochar a good soil amendment for home gardens?

To answer this question, University of Minnesota Extension Master Gardeners and Iowa State Master Gardeners tested the productivity of vegetable and flower gardens amended with biochar at four Minnesota sites and three sites in Iowa from 2012-2015.

Demonstration gardens were planted each year with typical garden plants such as tomatoes, peppers and zinnias in beds that were applied with biochar prior to the first planting in year-one on the project. No further biochar was added during the duration of this project. These gardens were planted and maintained each season by Extension Master Gardeners and youth volunteers.  Growth and yield measurements were taken on plants at designated times of the season and compared across the sites to help determine any positive or negative effects of biochar on the garden plots.


  • Julie Weisenhorn, University of Minnesota
  • Lynne Hagen, University of Minnesota
  • Yvonne McCormick, Iowa State University
  • Cindy Hayes, Iowa State University
  • Denny Schrock, Iowa State University


Research Summary

  • University of Minnesota Extension Master Gardener Biochar Research Summary (Julie Weisenhorn)

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