The humble earthworm has suddenly become headline news in vineyards. Scientists, consultants, and a growing number of producers warn that repeated tillage, soil compaction, and heavy chemical use in many vineyards make life difficult for these tiny soil engineers — and losing them could harm both soil health and the quality and resilience of winegrowing landscapes.
According to The Guardian, scientists and winemakers are now urging vineyards to change how they manage the ground beneath the vines so that worms can return and do what they do best: aerate the soil, recycle organic matter, and rebuild biological life
For decades, vineyards have been kept deliberately “tidy”: tractor wheels roll between rows, the soil is kept bare to control weeds, and sprays and fungicides are applied to protect grapes. Those choices can make vineyards inhospitable to many soil organisms. Yet earthworms—epigeic, endogeic and anecic species—are central to soil function; their burrowing and castings change the physical structure of soils, increase water infiltration, and speed nutrient cycling. A broad review of vineyard ecology shows that tillage and pesticide regimes are among the principal drivers of lower soil biodiversity in vineyards, and that reducing disturbance and increasing plant cover are two of the most reliable ways to recover soil life.
In This Article
- What Earthworms Actually Do for A Vineyard
- Real Winemakers and Consultants Showing How it Works
- What Regenerative Viticulture Could Mean for Wine Regions — and What to Do Next
- Actionable Advice for Growers and Regions (Practical First Steps)
What Earthworms Actually Do for A Vineyard
Earthworms are not just “nice to have” — they are ecosystem engineers. Their burrows allow water to soak in rather than run off, their feeding mixes organic material into the soil, and their castings act as a slow-release, microbiome-rich fertiliser that helps roots access nutrients. The analysis also highlights a clear link between higher earthworm abundance and improved soil aggregation, carbon cycling, and water regulation — all crucial for vines facing more erratic seasons and more frequent droughts. The authors of the Frontiers paper emphasise that tillage reduces earthworm numbers, while cover crops and organic amendments boost them and strengthen multiple soil functions.
Practical soil-health guides used by growers reach the same conclusion. A UC Davis–led survey in Napa Valley sampled 62 vineyards and more than 500 soil cores to create a baseline for soil health across management styles; the guide emphasises four core principles that support biological life: keep living roots present, keep soil covered, maximise biodiversity and minimise disturbance — all directly relevant to protecting earthworms.
Those functions matter beyond the microscope. In the face of hotter summers and uncertain rain, soil that holds water and supports diverse microbes gives vines a better chance to ripen grapes with balance rather than stress-driven sugar spikes or disease outbreaks. A growing body of research on regenerative viticulture suggests that practices that rebuild soil and biodiversity can make vineyards more resilient to climate extremes — not by an immediate miracle, but through cumulative ecological improvement.
Real Winemakers and Consultants Showing How it Works
This is not just an academic conversation. Several real-world examples show how changing basic soil management can revive life beneath the vines. In Kent, UK, Ham Street Wines faced exactly the problem scientists describe: freshly planted rows that, after conventional planting and a season of tillage and sprays, had “dead” soil with virtually no worms. The owners quickly converted to organic and biodynamic practices, introduced long cover crops and heavy mulches, and began to see worm counts rise from nearly zero to dozens per spadeful within a few seasons. “We want life in our soils,” one owner told reporters, and the hands-on soil pits they dug made the problem clear. The Guardian reports that consultants working with vineyards believe similar recoveries can often be seen within three to five years of sustained cover-crop, mulch and low-disturbance regimes.
In the United States, another side of “worms in wine” has emerged: vermifiltration in wineries. Some producers are now using earthworm-based wastewater treatment systems — notably Biofiltro’s BIDA systems — to clean winery grey water and generate nutrient-rich worm castings. Operators report that the technology removes the vast majority of contaminants while producing a valuable soil amendment. A small but growing number of wineries in California, Oregon, and Washington have already adopted these systems. Wine Enthusiast reports that nine wineries in the U.S. had installed worm-based treatment systems by 2023, with more in the pipeline, and several large operations now run modular worm beds capable of treating millions of gallons a year. These are different interventions — one focused on living soils in the field, the other on using worms as a green technology in the cellar — but both show a shift in how the industry values soil biology.
Experts who study soil biodiversity warn that not all chemicals and practices are equal. Some fungicides and persistent compounds, such as copper, accumulate and reduce the survival and activity of earthworms and other soil fauna; by contrast, organic amendments and reduced mechanical disturbance tend to increase abundance and diversity. That is why integrated, place-based changes — matched to local soil texture, climate and grape variety — are the most practical route forward.
What Regenerative Viticulture Could Mean for Wine Regions — and What to Do Next
Regenerative viticulture is the name many practitioners give to a set of practices that prioritise soil health, ecosystem function and whole-farm resilience. A cross-disciplinary review and a January 2025 evidence synthesis released by the Regenerative Viticulture Foundation concluded that, overall, practices such as cover cropping, diverse sown vegetation, organic inputs and minimised tillage can boost soil organic matter and biodiversity, sequester carbon, and increase resilience to temperature and rainfall swings. These benefits are not uniform everywhere — soil type, local climate and historical management shape outcomes — but the weight of evidence supports a strategic shift in many regions.
For wine regions, the implications are significant. Healthy soils reduce irrigation needs in some settings, stabilise yields under stress, and often lower pest and disease outbreaks as biological control pathways recover. Consumers and markets are increasingly aware of production methods, so producers adopting regenerative practices may gain both ecological and reputational benefits. However, conversion is not immediate, and trade-offs exist: crop protection, fruit yield, and “terroir expression” remain real concerns for producers who have built businesses on consistent wine styles. This is why robust monitoring—through soil tests, simple biodiversity checks like earthworm counts, and region-wide knowledge sharing—is essential. The UC Davis Napa soil-health project is one example of how baseline data can guide practical, measured change in vineyards.
Actionable Advice for Growers and Regions (Practical First Steps)
Start with measurement: dig soil pits and count earthworms, measure soil organic matter and aggregation, and sample both vine rows and tractor rows separately to compare differences in compaction and biology.
Experiment with alternating permanent grass cover or sown cover crops in inter-rows; even partial, well-chosen cover cropping has consistently been shown to increase microbial biomass and support earthworm populations. Minimise mechanical tillage—where feasible —reduce or eliminate regular inversion, and instead cultivate through mowing, mulching, and targeted shallow work.
Add organic matter using composts and mulches rather than relying solely on synthetic fertilisers. Finally, where water treatment is a concern, explore vermifiltration systems for winery water reuse; these can reduce chemical use and produce a valuable soil amendment. Together, these steps reflect both scientific guidance and the practical experience of growers in the field.
Conclusion
Earthworms are a practical indicator and a practical tool. The science shows they matter; early adopters in the field and in the cellar show how to bring them back; and emerging regenerative frameworks provide a roadmap for regions that want to keep producing wine while rebuilding the very soils the vines depend on. For winemakers and region-wide bodies, the question is less about ideology and more about strategy: measure, pilot, monitor, and scale the practices that restore biology and resilience.
