By Andi Anderson
Michigan hop growers are being encouraged to remain highly alert as crops enter the important flowering and cone development stages. During this period, effective monitoring and management of diseases and insect pests are essential to protect crop quality, yield, and profitability.
Several fungal diseases remain major threats to hop production in Michigan. The most significant include hop downy mildew, halo blight, and powdery mildew. These diseases thrive in the region's moist and temperate climate and are responsible for substantial crop losses each year.
Experts recommend an integrated management approach that begins with healthy planting material, regular field scouting, proper sanitation practices, and the use of preventive fungicide programs.
Growers are also advised to follow fungicide recommendations carefully during flowering and cone formation. Well-timed treatments not only help manage major diseases but can also reduce the impact of secondary cone diseases such as gray mold, Fusarium cone tip blight, and Alternaria cone disorder.
Since weather conditions, application methods, and variety differences can affect performance, fungicide programs should be adjusted accordingly. Rotating or tank-mixing fungicide modes of action is also important to delay resistance development.
Insect activity has increased significantly across many hop-growing areas. Producers should continue scouting for European corn borer, potato leafhopper, two-spotted spider mite, rose chafer, and Japanese beetle populations.
European corn borer larvae can damage hop plants by feeding on vascular tissues, reducing the movement of water and nutrients. Early detection of adult moths and eggs is critical because management becomes more difficult after larvae enter the plant.
Potato leafhoppers also remain active. Their feeding can damage leaves, reduce photosynthesis, and affect plant growth and crop performance. Young plants are particularly vulnerable to injury.
Two-spotted spider mites are currently a major concern because hot and dry weather favors rapid population growth.
Heavy infestations can cause leaf discoloration, reduced photosynthesis, defoliation, weakened plants, and significant economic losses. Experts recommend regular scouting and early intervention before populations reach damaging levels.
Rose chafers and Japanese beetles continue feeding on hop foliage. While established hop plants can generally tolerate moderate feeding damage, younger plants with limited leaf area may require additional attention and management.
Michigan State University Extension encourages growers to stay informed through newsletters, educational programs, and online resources. Producers experiencing unexplained crop symptoms are encouraged to seek professional diagnostic assistance through plant and pest diagnostic services.
In addition, growers using pesticides are encouraged to obtain pesticide applicator licenses. Proper training helps improve pesticide safety, regulatory compliance, and environmental stewardship while supporting effective crop protection practices throughout the growing season.
Photo Credit: gettyimages-npantos
Categories: Michigan, Crops