Microclimate and Vineyard Management Techniques
Microclimate is the combination of temperature, humidity, sunlight, and other environmental factors in the actual growing zone of the grape vines. This is the area within the leaf canopy, and extending out a foot or so outside the canopy. The art of the grape grower is to optimize the microclimate by adjusting the cultural practices to match the larger local climate and the needs of the grapes.
We do this both by careful selection of trellis styles, and paying strict attention to cultural practices that include pruning, training, shoot thinning, cluster thinning, and weed and turf management. The goal of our cultural practices are to maximize the sunlight available to each individual shoot, leaf, and grape cluster; providing just the right amount of sunlight to each one. If there are too many leaves and shoots, they compete for light, and none get the optimum level. If the shoots and leaves are overgrown, then too little light gets to the grapes. Grapes need sunlight exposure to develop ripe flavors and stable colors, but too much sunlight at the wrong times can cause sunburn and damage to the grapes.
Most of our grapes are grown on Vertical Shoot Positioned (VSP) trellises. This is probably the most popular style for advanced winegrowing worldwide because it allows the grower to position each individual shoot for optimum performance, and it also allows easy access to the vines for pruning, training, and harvest. Our more vigorous varieties are grown on a modified Ballerina trellis that features panels of shoots growing both up and down from the main arms of the vine. This provided two fruiting zones, and over 8' of total canopy height. This taller trellis helps to manage the vigor of these grapes by increasing both yield and quality to keep these vigorous vines in balance. Some of our native and hybrid grapes are grown on the Geneva Double Curtain system, developed by Cornell University to take advantage of the habit of these grapes to trail down rather than to climb up.
Regardless of the trellis style, it is vital that the canopy be kept as narrow as possible to allow light and air penetration, and for proper chemical penetration. See these practices in use at our Photo Album page.
Finally, we use a combination of cultural practices to optimize the moisture and nutrient balance of the soils around the grapes. Our ability to plant on hillsides allows us to channel excess water away from the vines to reduce soaking and overwatering. We maintain a weed-free soil line under the vines to reduce sources for mold spores and to reduce harbor for rodents and damaging insects. We maintain turf between the rows to moderate soil moisture through transpiration, to provide some competition for nutrients, and to control erosion on our hillsides. The use of tight slow-growing turf grasses reduces our need for herbicides that could harm the vines and the environment.