Organic, locally produced strawberries are in high demand in the Upper Midwest. Day-neutral cultivars fit well within an annual production system, allow growers an extended harvest period, and previous research shows they can be productive in our region. However, key production challenges limit adoption of organic production of day-neutral strawberries including weed, insect, and disease pressure. To address these challenges, we established controlled experiments investigating the effects of four different mulch types: white-on-black poly (standard), black poly, reflective metallic poly, and biodegradable paper mulch on yield and quality of ‘Cabrillo’ strawberries across two years (2022 and 2023) and two locations (Madison, WI and St. Paul, MN). Our results show that strawberry yield ranged from 5,000 - 18,000 lbs per acre across treatments and years. The highest yields were achieved in 2023 in Wisconsin in the reflective metallic poly treatment, which was significantly different from the white-on-black treatment in the same year. Proportion marketable yield was equal between treatments in both years in Wisconsin and in 2022 in Minnesota, however we observed a significant decline in marketable fruit quality in Minnesota in 2023 under the paper treatment compared to black plastic.The paper mulch broke down before the end of the production season in Minnesota in both years which led to increased weed pressure and reduce fruit quality; however paper mulch retained at least 90% coverage and integrity in Wisconsin across both years. Tarnished plant bugs (TPB) are a key pest in this system and will significantly reduce fruit yield and quality if not managed. In both Minnesota and Wisconsin, TPB damage was higher in our standard white-on-black poly compared to the reflective metallic poly mulch in both years. In addition, thrips counts were significantly higher on white-on-black poly compared to reflective metallic poly in Minnesota in both years. Anthracnose fruit rot was the most common disease observed and was most common in the white-on-black poly treatment. Anthracnose was also a significant problem on row edges where weeds were actively growing and retaining moisture near the fruits. Overall, reflective metallic poly mulch significantly reduces strawberry insect pest pressure while maintaining yield and fruit quality and outperforms the current grower standard white-on-black plastic mulch. Price premiums for organic strawberries marketed direct by growers combined with the longer day-neutral production season, make day-neutral strawberries financially lucrative despite production issues and high labor requirements.
