Blackwood Canyon's Vineyard Management Philosophy
The main management goal of Blackwood Canyon Vineyards is simple: grow grapes that produce world class wine. However, accomplishing this is not that simple.
To grow the highest quality grapes one must first understand grape physiology. Grapes are a vine. The vine's goal is to occupy as much territory as possible. The vine has two ways of doing this, one, vegetative growth, and two, reproduction or fruiting. Given enough water and nutrients a vine will personally or vegetatively cover as much area as possible, which it generally achieves through leaf and shoot growth. Given water, nutrients, and a favorable climate, one vine can occupy a huge area. When a limiting factor occurs, typically reduced water and/or nutrition, a vine will cease its vegetative mode turning to reproduction so that its descendants will occupy the space that this vine found it couldn't.
We grape growers have a different goal than the vine. We desire quality fruit, not for the vine to occupy as much territory as possible. Therefore, to give the vine everything that it desires is not conducive to our goal. We want the vine to work for us, not us for the vine. Our goal at Blackwood Canyon is to grow fruit that produces wine that will compete on a world-class level. We manage our vineyards to maximize our fruit quality, not our tons per acre.
To grow the highest quality grapes, one must understand how to grow fruit, not leaves. In addition, the flavor of a grape is in the skin, not the juice. This means that to achieve our goal of quality fruit, we must control the vegetative desire of the vine. By limiting leaf and shoot growth, we force the vine to transfer it's energy from vegetative growth to grape cluster development. Then, by manipulating growing conditions, we control the fruit development.
Again, The flavor of grapes are in the skin. The smaller the berry size the greater the skin-to-juice ratio, the greater amount of flavor. In short, we want to grow small berries with the minimum balance of leaves-to-fruit that supports the crop load.
Dr. Smart of New Zealand, considered the world's canopy expert, maintains that a vine needs 10 leaves per cluster to ripen under conditions in New Zealand. Washington State, being warmer, requires less. Dr. Wample of Washington State University believes 5 to 7 leaves per cluster to be more accurate for Washington, and we generally agree. From these figures, one can see that a large canopy is not required. In fact, a large canopy is detrimental to fruit quality; the dense interior only creates humid, low-sunlight conditions that promote disease and poor fruitfulness, while removing energy from the plant. Only the leaves on the exterior of the canopy create net energy gain. The leaves inside the canopy, not having the benefit of sunlight, consume energy, thus requiring the exterior leaves to feed the interior leaves. This means that a dense canopy is feeding leaves at the expense of the fruit. In short, canopies with the majority of the leaves on the exterior maximize efficiency. The big plant is not better.
To optimize fruit quality we desire flavors - not only proper flavors but intense flavors. By controlling vine growth and nutrition, we can optimize flavor. Example: a knowledgeable viticulturist can make Merlot taste anywhere between a bell pepper to a black cherry. Controlling vine vigor does the majority of this. Large vigorous vines will cause bell pepper characteristics, whereas moderate to low vigor vines produce deep black cherry flavors. Intensity is attained through controlling berry size. The smaller the berry, the more intense the flavors.
This brings us to how we manage the vines at Blackwood Canyon. We try to grow moderately vigorous vines that produce small berries, thereby producing fruit with the flavors and intensities that are required to make world class wine.
Blackwood Canyon exists to make wine, not process grapes.
Grapevines have three major growth stages: Grand Period of Growth (GPG), berry sizing, and fruit maturation. GPG is the proper vegetative period for a vine. GPG starts at budbreak and ends at bloom. GPG is when we try to grow the vine canopy. We attempt to maximize growth without becoming overly vigorous. Over-watering and/or excessive fertilization will cause extreme vegetative shoot growth or the large, dense canopy that we do not want. Not only does this lower the fruit quality, but it also leads to poor wood development. Improper wood quality causes poor fruitfulness the following year and increases potential winter damage. At the end of GPG one should notice, upon inspection, three important things at Blackwood. One, the vines have achieved a canopy capable of ripening the crop, allowing future stress-management. Two, moderate internode length of 1 to 2 inches, indicating proper shoot growth. Three, bloom occurring typically one week earlier than surrounding vineyards, which indicates that the plants are transferring their emphasis from leaf production to fruit production.
The next stage is berry sizing. This is when stress becomes very important. By further reduction of water and nutrient availability, the transition is completed from the vegetative mode of GPG to fruit production. If the plant is not controlled at this time vegetative growth continues, resulting in large berries and vegetable flavors, lowering fruit quality. As we have already achieved the canopy required to ripen the crop, restriction of shoot growth is very beneficial. Most farmers continue high vigor growing conditions through this period. This only causes problems. The dense canopy causes disease problems with increased chemical sprays to control them. The vigor produces large berries and uncontrolled flavors. The farmer loses quality and increases cost, work, and pollution.
The end of berry sizing is marked by veraison or color change. The berries have reached the majority of their size and are beginning to ripen. At this time we are stressing the vine so they produce the desired flavors and to promote lignification of the shoots in preparation for the winter. The fruit is monitored for harvest with picking dates determined for optimal flavor and intensity. After harvest, the vines are allowed to store carbohydrates for the winter before going dormant.
In perspective, high quality fruit is managed, it does not just happen. There is more to growing grapes than pruning, watering, spraying and picking. A knowledgeable viticulturist can be the number one quality factor when using proper controls.