At Cave Spring Vineyard, we believe that to produce the best wines you must begin with the cleanest fruit possible. Above all, this means controlling fungal infections on the vine and its fruit. In certified organic vineyards, these diseases are controlled mainly using the natural elements of sulphur and copper, along with sodium bicarbonate and sodium metabisulphite, all of which we employ extensively. In fact, these materials comprise 30 to 50% of our fungicide regime, depending upon the season. However, if these substances are used to the exclusion of other treatments, toxic accumulations of the heavy metal copper, in particular, can build up in the soil to the point where they impede the uptake of vital nutrients by the vine’s roots, thereby threatening overall vine health. Moreover, the frequency of application in an organic spray regime is increased by up to two times that of a more balanced, sustainable program. By implementing a treatment regime that balances organic and synthetic elements we use 40% less fuel. Overall, this program has lowered our carbon footprint and has contributed to healthy soil and crop productivity. Additional spray treatments necessitated by organic methods involve a significant increase in tractor usage and, hence, greater fossil fuel consumption and soil compaction. The latter is particularly detrimental to soil structure and microbiology, thus compromising the health of the vine’s root system.
Weed proliferation is another threat that can increase fungal disease pressure if left unchecked. On this front, we also employ a mixture of techniques. For example, we sow a mixture of grasses between the rows that impede weed growth, prevent erosion and improve nutrient levels and water availability in the soil. We also hill-up the soil beneath the vine canopy in the fall.
This is done partly to protect the vine trunk from winter injury, especially for younger vines. More importantly though, hilling?up helps to control weeds beneath the vines. Come springtime, as the weeds begin to sprout, the hill of earth is tilled, thereby preventing weed proliferation. This form of mechanical cultivation is repeated during the growing season and serves not just to stunt weed growth, but also to till and aerate the soil. Most importantly, this technique allows for increased airflow beneath the vines which in turn aids in preventing harmful mildews and molds from developing in the vine’s fruiting zone, thereby reducing the frequency of fungicide treatment. While we are continually working to reduce our use of herbicides, we do apply them sparingly to supplement mechanical methods, always selecting materials for their ability to control specific weeds while minimizing their impact on the natural environment of the vineyard floor.
Another threat in the vineyard is insects, which is generally not a major problem in the Niagara Peninsula. Unlike more temperate wine regions, our northern climate has the advantage of cold winters that naturally control insect populations of all kinds. Where there are threats, however, we use natural methods as much as possible. By maintaining healthy ground cover and soil conditions, we provide an environment in and around our vineyards that encourages the proliferation of beneficial predatory insects to control pests such as grape berry moth, leafhoppers and mites. Pest populations are measured and scouted parcel by parcel and any intervention using insecticides is highly targeted and absolutely minimized.
As the grape clusters reach veraison and continue to ripen through to harvest, certain bird species become an issue in our region. Starlings, in particular, can ravage the crop by damaging clusters, which, in turn, can cause the rapid spread of rot. In addition to the use of re-usable netting to protect vulnerable areas of our vineyards, our site also benefits in this regard from its unique environment. The spectacular limestone cliffs of the Niagara Escarpment above Cave Spring Vineyard provide the perfect natural habitat for many species of predatory raptors, including Red-tailed, Broad-winged and Sharp-shinned Hawks as well as Northern Goshawks and Turkey Vultures. We manage the forests surrounding our vineyards so as to attract these rare and beneficial birds of prey, many of which help greatly in warding off flocks of Starlings.
One final aspect of our vineyard management is soil management. Here we implement completely natural techniques. For example, we make our own compost, which is composed of manure from local farmers and grape pressings (pomace) from our own wine production, spreading it throughout our vineyards. As well, the selection of grasses that we sow between the rows, which helps to squeeze out unwanted weeds and discourage erosion, is tilled into the soil annually. Both of these techniques are designed to augment the organic matter in our soils and maintain healthy soil ecology.
Cave Spring Vineyard is blessed with very balanced soil structure throughout its many parcels. The soils are quite rich and fertile given that they were largely fallow fields and pasture prior to the establishment of the first vines in 1974. As a result, very few additions are needed to supplement the natural fertility of our soils. However, to ensure a proper balance in the vine canopy, soil and leaf samples are analyzed throughout the growing season. From this information, nutrient amendments of nitrogen, potassium, calcium and magnesium, along with micronutrients, are made, but only when necessary. As well, foliar applications of kelp and calcium are sprayed to help elongate the clusters and strengthen the berry skins in an effort to combat the onset of fungal disease.
Many of the practices and controls that we employ in the vineyard are natural and sustainable. However, if disease undoes the great effort that goes into training the vine from bud break through harvest, resulting in great loss of yield, winemaking quickly becomes economically unsustainable. With this in mind, we find that an integrated approach using natural techniques and elements as much as possible to prevent disease, combined with highly targeted and minimal interventions only when necessary, provides for an optimal balance of sound fruit, soil conservation, vine health and above all, wine quality.