Maintaining a healthy vineyard means looking beneath the surface — literally. In Episode 075 of Vineyard Underground, Fritz Westover and Dr. R. Paul Schreiner dive into the fascinating world of mycorrhizal fungi and how these microscopic allies can dramatically boost vineyard performance. With Fritz’s practical viticulture perspective and Dr. Schreiner’s decades of root biology research, this episode brings valuable insights for vineyard managers seeking to optimize soil health, nutrient uptake, and drought resilience.
Why These Fungi Matter
Mycorrhizal fungi form symbiotic relationships with grapevine roots, significantly improving the vine’s ability to absorb water and key nutrients, especially phosphorus. In low‑P soils, these fungi enhance phosphorus uptake, while also helping with micronutrients like zinc and copper. That means healthier foliage, stronger vines, and potentially better crop yields.
Key Influences on Fungal Health
- Fertilization practices: Heavy nitrogen or phosphorus applications can suppress fungal colonization. Balance is essential — over-fertilizing may reduce the natural benefits of mycorrhizae.
- Soil disturbance: Frequent tilling, herbicide use, or improper cover cropping can disrupt fungal networks. Minimizing disturbance promotes a robust underground ecosystem.
- Inoculation vs. natural presence: While many vineyards host native mycorrhizal fungi, Dr. Schreiner discusses when commercial inoculants are beneficial, such as in young vineyards or replant sites.
Takeaways for Vineyard Operators
- Support native mycorrhizae by reducing soil disturbance and managing precise and strategic fertilization practices.
- Test before you inoculate: Soil assays can reveal whether native fungi are already abundant.
- Target inoculation strategically in replant situations or highly disturbed soils.
- Informed nutrient timing: Integrating fungal health into tissue sampling and fertilizer scheduling improves our understanding of overall nutrient management.
Looking Ahead: Vineyard Nutrition Research
Dr. Schreiner shares progress from the High-Resolution Vineyard Nutrition Project, which is redefining best practices for tissue sampling — comparing leaf blades versus petioles — to optimize how we monitor nutrient health. Their ongoing work aims to provide precision tools for fertigation timing and improved vine performance.
Final Thoughts
Focusing on the hidden fungal networks beneath our vineyards can yield visible benefits above ground. By harmonizing soil practices and nutrient management, growers can foster thriving vines that are more resilient and efficient. If you’re planning a new vineyard or looking to enhance an established one, tuning into the relationship between roots and fungi is a smart move.
Want to learn more? Listen to Episode 075: “The Importance of Mycorrhizal Fungi for Vineyard Health with Dr. R. Paul Schreiner.”
