Boxwood Blight - A 15 Year Love and Hate Relationship

HRI Research • March 29, 2021

German researchers have been working on boxwood blight since it first appeared in Germany in the summer of 2004. Initial cultivar trials indicated that there were large differences in susceptibility. This resulted in a series of horticultural trials, on the one hand on the susceptibility of Buxus species and cultivars, and on the other hand on alternative woody plants as substitutes for boxwood. In parallel, many trials on the suitability of fungicides have been running since 2005, both in vitro and in the field. In addition, the trials have repeatedly tested preparations that were considered as alternatives for chemical plant protection. Furthermore, we monitored the occurrence of the two blight pathogens, Calonectria pseudonaviculata and C. henricotiae, and examined other host plants - Pachysandra and Sarcococca in trials. This talk will summarize the 15-years of research results and share the successes and difficulties of blight control in gardens and parks in Germany.

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Meet the HRI Leadership Academy Class of 2026: Ten Industry Leaders Shaping the Future of Horticulture

By Jennifer Gray • July 23, 2025
COLUMBUS, OH – July 22, 2025 – The Horticultural Research Institute (HRI) and AmericanHort are proud to announce the HRI Leadership Academy Class of 2026, a cohort of accomplished professionals from across the green industry who are poised to take their leadership to the next level. These individuals, representing various industry segments and career paths, were selected for their commitment to horticulture and their desire to help shape the industry's future. The HRI Leadership Academy is a one-year advanced leadership program designed for experienced horticulture professionals looking to elevate their influence and expand their strategic thinking and business skills. Built around in-person classes, peer collaboration, and mentorship, this program prepares leaders to confidently navigate business challenges, drive innovation, and spark positive change in their businesses, the industry, and their communities. 

Prospecting for Biocontrols

By Jennifer Gray • March 14, 2025
It is neither economically sustainable nor environmentally acceptable to make multiple fungicide applications to protect boxwood, a key nursery crop and iconic landscape plant, from boxwood blight.
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Horticultural Research Institute Opens Grant Proposals for Fiscal Year 2026 Funding: Supporting Horticultural Innovation and Growth

By Jennifer Gray • March 10, 2025
Columbus, OH - The Horticultural Research Institute (HRI), the research affiliate of AmericanHort, is excited to announce that it is now accepting research grant proposals for fiscal year 2026. HRI’s competitive grants program supports projects that directly impact and advance the green industry, providing funding for research on significant topics such as plant health, pest management, understanding consumer behavior, production efficiencies, and quantifying plant benefits.
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