The Effects of Plastic Mulch Choice on Hemipteran Populations, Soil Temperature, and Productivity of Lavender (<em>Lavandula</em> × <em>intermedia</em>) in an Ohio Brownfield: A Participatory Approach

Lavender has shown promise as a specialty crop in the Rust Belt cities of the midwestern United States; however, production in these regions can be challenging due to harsh winter conditions, cosmetic damage and disease transmission from hemipteran pests, and a lack of information on best management practices in urban settings. This study uses a participatory research approach to address soil and pest management issues at a small-acreage lavender operation in Ohio. A 2-year field experiment was designed collaboratively with land managers to compare the performance of current mulch practices (black landscape fabric) with the use of silver, dark, and embossed dark plastic mulches on hemipteran insect populations, soil temperature, and leaf area of lavender plants. This experiment used a combination of sticky trap sampling, soil temperature data loggers, and leaf area index sampling. While mulch effects varied by year, silver mulch had significantly lower hemipteran populations in the first year and soil temperatures were significantly higher in blue mulch during both years. Lavender leaf area was significantly greater in red mulch relative to blue mulch but neither mulch treatment showed a significant difference in leaf area compared to the control (black landscape fabric). Finally, there was no evidence of indirect effects of soil temperature on plant growth. These results indicate that the effects of plastic mulch on soil properties, hemipteran insect populations, and lavender development vary by color and texture. Thus, the selection of plastic mulch should be based on specific management issues.