Vineyard Through the Seasons
A vineyard goes through many phases with many changes during a year. Below, we highlight the major phases and their general timing in our vineyard that is in the premium grape growing appellation called Escondido Valley in West Texas. All vineyards go through these phases but the timing of each is dependent on the climate, to a large extent, and the soil, to a smaller extent, of the vineyard.
Dormancy occurs in our vineyard from early November to early/middle of March. This is a time when the vines take a break and protect themselves from the colder weather that is coming. Thus the sap in the vines goes to the roots that are underground and safe from the elements above ground. Accordingly, the vine loses all of its leaves.
Cold weather, rain, and even snow are good during this phase. Cold weather conveys to the vine that it is unsafe to come out, i.e. go into bud break, and rain or snow provides great moisture to the soil. We like the vine to stay in dormancy as long as it can, thus a cold winter is good since, once a vine goes through bud break, the buds that ultimately become grapes are at risk to any late spring freeze.
This being said, really low temperatures can be a problem. We generally do not want temperatures below 10 degrees for any extended period, as very low temperatures can kill a vine while in dormancy. We call this “winter kill.” This problem is very rare for us and has only happened with some very young and some very old vines in one year since we first planted the vineyard in 1981.
We start pruning in February and end around the middle of March. It is important to prune a vine while it is in dormancy, or just coming out of dormancy, so there is not a lot of sap flowing throughout the vine. Proper pruning has to be done by hand and we have approximately 150,000 vines to prune, so this is a big job. We prune late bud breaking varieties such as Cabernet Sauvignon and Merlot first as there is less risk for these varieties to bud break early and be exposed to late spring freezes. Conversely, we prune early bud breaking varieties, Chardonnay, Chenin Blanc and Pinot Noir for example, last as pruning the vine sends a little signal/shock to the vine that conveys it is too early to bud break. This delay helps us slow down bud break between 4 and 7 days and decreases, by a little bit the risk associated with late spring freezes.
Pruning involves cutting the shoots down to the cordons of the grape vine to leave a certain number of buds that will grow to produce leaves and fruit. This is our way to increase quality and manage the life of the plant by limiting the amount of grapes and leaves it has to focus on.
Bud break starts with earlier bud breaking varietals like Chardonnay, Chenin Blanc, Pinot Noir and Muscat Canelli in the first 2 to 3 weeks in March followed by the later bud breaking varietals of Merlot, Petite Sirah and Cabernet Sauvignon. These later budding varietals start to come out the last week in March and the first weeks in April. Varietals that tend to bud break after the early ones and just before the late ones, are Alicante Bouchet, Sauvignon Blanc, Syrah and Zinfandel.
The timing of bud break is consistent throughout the development of the grape, i.e. grapes that bud break early, flower early, go through veraison early, mature early and are harvested earlier than the ones that bud break later.
We recognize six stages of bud break from the start to the finish. This is when buds begin to push out to become the shoots of the vine with leaves and tiny clusters, that once pollinated, will become grape clusters.
We plant between 20 and 40 acres a year, both to rejuvenate and expand our vineyard. We generally plant at the end of the 2nd and the 3rd week of April. We plant varieties that we know from experience will grow well in terms of quality and quantity in our vineyard, and test varieties that we think will grow well.
The decision of what to plant has many variables which include risk (given our threat of late spring freeze), quality, quantity, versatility (i.e. how well the variety can work well with others we grow), our needs, market demand, etc.
It takes three years from the day we plant a vine until we get our first harvest. This first harvest is generally 50% of the quantity that the vine will produce and generally is below the quality that the vine will produce in later years.
There are a lot of decisions to make once you decide on the variety. These include the clone of the variety, what rootstock to use, what nursery to work with and where in your vineyard to plant this variety. We have to make these decisions two years before we plant. This enables us to choose the clone we want and the rootstock we want from the nursery we choose to work with. The nursery grows the rootstock we select for a year. When this rootstock is dormant the nursery grafts our selected clone to this rootstock. The vine is then replanted for another year. After it becomes dormant in the second year it is harvested and shipped to us in its dormant phase. We then plant it and it bud breaks and grows.
The clone and rootstock decision is driven by the weather and soil in your vineyard and the desired yield and quality you want to achieve.
There is a tremendous amount of work that goes into getting a newly planted vine to production in the three years and, unfortunately, most of this work has to be done by hand. This includes pruning, training/tying, weeding/cleaning, suckering, fertilizing and irrigating.
Grapes are self pollinating. Generally, throughout May, flowers develop around the non-pollinated, small, hard green clusters that will become grapes. These flowers pollinate the clusters and then the flowers expire and fall off. This process enables the grapes to grow, develop sugar and essentially mature.
Veraison is the process of sugar development in the grapes. As sugar is developed in the grapes the grapes begin to change color and the new shoots of the vine begin to harden, i.e. transform from green/flexible shoots to harder wood shoots with little, then no flexibility. All grapes start out green and then, through this process, develop into their final color, i.e. dark red, burgundy red, gold etc.
Once the grapes complete veraison they are close to maturity and getting ready to be harvested. Deciding when to harvest involves many variables and we use several tools to make such a decision. In the vineyard, we use a refractometer. A refractomer measures the sugar level in the grapes. We call this sugar level Brix. We like to harvest when sugar levels are between 23.5 and 25 Brix. The amount of sugar defines the amount of alcohol the grape can produce when it ferments.
The Brix level is just one variable and others, like acidity and pH levels, must be taken into consideration. To fully analyze grapes, we take samples from the rows in each block and analyze them in our lab.
Ultimately, these analytics give us a good guide but the final decision is made by the winemaker who uses their experience and their taste buds, along with the analytics, to make the decision on when to harvest. Maturity is determined by balance of sugar, acidity, pH, and color and the decision to harvest is driven by the kind of wine one ultimately wants to make, i.e. a wine with higher acidity, one with higher or lower levels of alcohol etc.
We harvest mechanically and at night for several reasons.
- Mechanical harvesting has improved so much in the last 20 years in terms of quality that many premium vineyards in premium appellations around the world, like Napa and Sonoma, are harvested mechanically.
- At night it is much cooler, 20 to 30 degrees cooler than in the day, and this
has many benefits:
- The grapes come off the vines more efficiently and effectively when they are not hot which makes the grapes’ skin rubbery.
- Our winery is adjacent to our vineyard so we are able to get the grapes into the winery quickly and in their freshest state and this translates to better quality.
- It is easier for us to work when it is cooler.
Once grapes are harvested the next level of work begins...winemaking.