While the vines are now dormant, Winter in the vineyard is still a busy time that sets the foundation for the coming year. During this time, we are pruning the vines which is a critical step forward in the annual growing cycle of the vine. Pruning can be divided into two major styles: cordon pruning and cane pruning.
Cane pruning involves building a lateral arm system that has spur positions. Spurs are last years shoots that are typically cut back to two buds. Each spur would then grow two shoots and we would expect two clusters per spur. Cane pruning takes one year old canes from last year and uses those buds for growing positions in the coming vintage. Cane pruning is the most common pruning technique in Oregon for several reasons.
Oregon primarily grows Pinot Noir which is known to produce less clusters and smaller clusters than most varieties. The climate in Oregon is very cool, especially in the spring when bud derivation takes place. What this means is that the number of clusters a bud will produce this growing season was determined last spring. So cool wet springs tend to mean less clusters the following year and warm dry springs tend to equate to bountiful vintages the following year. Because the buds on the one year old cane have all been exposed to sunlight they tend to be more fertile.
We have learned that by cane pruning we are able to increase the number of clusters. Furthermore, there is also occasional cold damage from extreme cold that can harm a portion of the upper vine structure. Since we lay down new canes every year, we have less concern about the effects of cold damage versus if we were spur pruning and had to rebuild the cordon. The cost of cane pruning is about 1.5 to 2 times as expensive as it takes a lot more labor to prune and tie down the new canes every year.