This chapter is coming to you a week or so later than I planned. Real life in the form of a consulting trip to Texas played hell with my recent schedule - my apologies for the tardiness. I didn’t know exactly where to place this chapter within the section on wine growing. At first, I thought it might make a good opening chapter for the section, but on further thought I decided that it would be better to talk about the course of the growing year after all the major operations had been covered in some detail. So, I have placed it near the end. I believe this chapter will be most useful for winemakers without a great deal of vineyard management experience as a reminder of the basic activities they should be focusing on in the vineyard during each portion of the year.
Chapter 13 -The Growing Year: a calendar of sorts for the winemaker
Closely observing each stage of the annual growth cycle will give the winemaker the best chance of tuning the crop to the demands of each specific vintage. The stages of the vine’s annual development, linked to the seasons of the year, are the logical organizing principles. As wine is grown in both hemispheres, under a relatively wide range of climatic conditions, a calendar based on months or weeks of the year would have little value.
There are two general approaches to vintage.[1] One is to adopt a fixed or formulaic philosophy of technique. This is idealistic, most likely motivated by a desire for, and belief in, a “best” way of doing things. This may be based on tradition or the winegrower’s own experience, but—regardless of origin— the result is a relatively inflexible recipe that is invoked each year for growing the crop and making the wine. This approach actually has the effect of exaggerating the differences between vintages. Vintages vary enormously, and if the same set of techniques is used for each, the difference between vintages will be large. Any given technique will have a variable outcome, as vintages differ across many parameters.[2] The second general approach is to vary techniques in response to variations in vintage. This is a targeted style philosophy. This approach does not rest on the concept of a best technique or an ideal recipe—it is pragmatic in nature. The vintner conceives the task as leveraging specific tools and techniques as needed, depending on the unique circumstances of each vintage. A fresh recipe is developed on the fly, as the growing year and vintage proceed. The winemaker has a specific style of wine in mind and will vary techniques significantly in response to the vintage, in order to shift the vintage closer to their stylistic ideal. This approach puts more demands on the winemaker’s knowledge and skills, as all factors must be considered anew for every vintage. While it is pragmatic, it is also far more creative than the fixed recipe method. Wines made using this philosophy will tend to have less variation between vintages.[3]
It will come as no surprise to the attentive reader that I am a strong proponent of the second, targeted-style approach, and my beliefs inevitably inform the discussion that follows. That said, I think the information will be helpful regardless of your philosophy, I am always trying to discover the means of directing the crop toward the goals I have set for both quality and style. It seems to me that letting nature take its course is relinquishing a certain creative participation in the process. A vineyard left to its own devices returns to field or forest, and a wine left on its own will surely become vinegar.
Winter: dormancy and pruning
While vines are dormant throughout the winter, the winegrower should not be. Thankfully, the winegrower can usually take a break for several weeks, from when the last wines of the vintage are barreled down to before pruning begins for the next season. This period coincides with the Christmas holidays in the northern hemisphere, and the wise winegrower will seize the opportunity for a hiatus from labor. It is one of the few times of year when there is little or nothing which must be done.[4]
Vines are a permanent crop. They are always strongly affected by the circumstances of the prior season and by their longer-term history of growth. Before pruning begins is the ideal time to review the prior growing season, and to consider any effects that may carry over to the upcoming vintage. Detailed notes and records should be kept and reviewed each year, to guide the grower in constructing a specific plan for upcoming vintages. At the very minimum, records of weather and the phenology of the vine need to be noted, as well as all operations carried out. These are then correlated with the results achieved as expressed by crop quantity and wine quality. These observations should be made regularly throughout the growing season on a block-by-block basis. In cases where significant variation exists within a block, even greater detail should be recorded.
The first question to be asked, and answered, before a single vine is pruned is the most general one: What will the vineyard’s general vigor and capacity be for the season? More specifically: Did anything occur in the prior year or years that may diminish the potential capacity of the vines for the next year? Many things affect the vine: Was the crop overly large? Did the first freeze arrive and defoliate the vines before they could store reserves post-harvest? Was there injury, disease, or drought pressure? The converse must also be considered: Will the vineyard have a larger than usual capacity? Perhaps the crop was smaller than normal in the prior season and the late season weather mild. Vines could then have the capacity in the next vintage for a larger than normal crop. And certain specific diseases and nutritional issues are best dealt with during the dormant season. Did your vines suffer from any of these? Were the potential cluster-per-shoot estimates from the dormant bud dissection normal? If not, then more buds should be retained at pruning.
If a winemaker is going to master only one vineyard activity, it should be the craft of pruning. This routine activity takes the most skill and has the greatest impact on the vine’s season. This is even more true of cane-pruned than spur-pruned vineyards. If one understands what a balanced vine looks like and how to achieve that through pruning, then a winemaker is well on the way to understanding winegrowing in general. The winemaker should always meet with vineyard management to discuss the goals of pruning before pruning begins. This is done on a block-by-block basis in each vineyard that the winery manages or purchases fruit from. During this in-person meeting, several vines should be pruned to ensure that all parties agree on the goal in a tangible way. It is a very good idea to follow up this initial meeting with a subsequent visit on the day pruning actually begins, to observe the crew at work. This will ensure confirm that the crew has been properly instructed and has the mindset for the job.
Early spring: budbreak to flowering
In the spring, as the buds swell and the first pale green leaves emerge, a joyful feeling arises. Yet again, the cycle of the vintage begins. Only a heart of stone can resist the allure of this time. The vines are beautiful on spring mornings when only a few leaves are showing, and bright green parallel lines seem to score the landscape. The first period of shoot growth is relatively slow, due to the cooler weather of early spring. This normally allows adequate time for the winemaker to assess each vineyard and block. Once five to seven leaves have unfolded on a vine, the winemaker will actually count the number of cluster primordia that have emerged and confirm the potential maximum number of clusters. This is more accurate than the information garnered from the bud dissections performed in late fall. It is essential to visit the vineyard at this time and get the first indication of the size of the crop. With this information, vineyard management can be guided in terms of the first shoot-thinning pass, normally performed when the shoots are 12–14" in length. If cluster counts are lower than average at this point, it is best to be conservative about removing any weak shoots bearing cluster primordia. Crowding around the heads of the vine can still be addressed by removing sterile shoots, even if all clusters must be retained. As the success of flowering and set is unknown at this point, it is best to leave more cluster primordia than you anticipate needing.
Disease control should begin as soon as leaves emerge, but in general the winemaker will not be involved in these decisions on a day-to-day basis. Shoot growth accelerates sharply toward the end of this period, and much attention must be paid to ensure newly emerging leaves are protected from disease. In some cases, foliar micronutrients may need to be applied in the pre-bloom period. The decisions for mowing and/or cultivating the rows occur early on, and in many areas frost control is a major concern.
Late spring/early summer: bloom and set
Bloom, also called flowering, will occur 50–80 days after budburst, depending on local weather conditions. The flowering and fruit set which follow are a critical period for the winemaker to spend concentrated amounts of time in the vineyard. The sequence of events during bloom presages to a degree the pattern of ripening that will occur in the fall.[5] Rain, wind, and especially cold conditions during flowering will interfere with fertilization. Each flower contains four ovules, so the maximum number of seeds that can be fertilized and formed is four. Under some conditions, fewer than four will be formed.[6] The number of seeds has a substantial effect on berry size. More seeds make for a larger berry, and optimal conditions during bloom will result in larger than average berries. Soil moisture post-bloom also plays a role in eventual berry size. Generous soil moisture will result in larger berries than drier conditions.
Keeping detailed notes on the course of flowering both within and between blocks is an essential practice. The date of full bloom should be noted for each block,[7] as should the duration of the bloom period, because this is an indication of the degree of variation within the block. Some conditions will make for a high degree of uniformity, such that all vines will be at the same bloom stage within a block. Other vintages may produce a bloom where individual vines are weeks apart in their stage of development. Vintages that produce a uniform bloom will tend to be more uniform in their ripeness, and the contrary is, of course, true as well.[8] The ripeness variation is not as easily detected at harvest time as it is at either bloom or veraison, which is why it is so important to note these differences. In a variable bloom scenario, styles emphasizing full ripeness will need to be picked even riper to offset the effect of lagging clusters. The berry begins its development at fertilization, and a cluster that blooms two or three weeks late will not catch up over the course of the summer. It will in fact remain behind throughout the season.
Once the bloom and set have finished, it is time to make the major fruit zone adjustments of leafing, lateral removal, cluster thinning,[9] and weak shoot removal. Not every one of these operations is needed each year. Normally, leafing and lateral removal are done as the first pass. This makes it much easier to undertake cluster counting to assess the success of set. While it is still too early to make an accurate estimate of eventual cluster weights, the experienced eye can make a rough judgment about whether the clusters will be of normal weight or otherwise. Much smaller or looser clusters than normal are more readily apparent than the opposite. If cluster thinning is needed, clusters should first be preferentially removed from weak shoots.[10] When cluster thinning’s goal is to lower the crop, secondary or tertiary clusters should be removed from the shoot rather than primary clusters. The latter are more desirable because they ripen earlier than the secondary or tertiary clusters. Shoots and clusters tend to crowd and bunch, both around the head of the vine and where the vines meet. These commonly overly vigorous areas of the vine often need attention. Even when the crop is balanced, these parts will need shoot and cluster thinning to allow airflow and to create a more disease-resistant fruit zone.
When done correctly, these operations are often the last hand passes until harvest. In situations with above normal vine vigor, it is wise to leaf more heavily post set, as vigorous vines will grow laterals whose leaves will block the fruit zone if the leafing was initially light. This in turn will necessitate another leafing pass; it is better to leaf a bit more extensively on the initial pass than to have to do it over again.
Summer: set to veraison
In some ways, the weather at this time of year has the least direct impact on wine quality. Spring and fall weather play far larger roles. The winemaker still needs to stay in contact with the vineyard, but the amount of oversight needed during summer is relatively low. After flowering and set, the moisture status of the soil has effects on berry size. In Mediterranean climates that are free from rainfall during the summertime, keeping vines in a moderate moisture stress will limit berry size. This is desirable in most cases for fine red wine.
Irrigation, when necessary, commences during this period. Irrigation needs to be controlled so that growth of new leaves and laterals ceases well before veraison. The onset of ripening will be delayed if active vegetative growth continues too late into the season. Though lush green growth may appear to be healthy, it is not consistent with the best wine quality. As discussed earlier in the section on irrigation the vine tolerates moisture stress well during this period. Vigilance must also be maintained regarding disease monitoring and control throughout this part of the year.
The first opportunity for accurately assessing crop size arises in mid-summer. Lag phase is the period that occurs 50–60 days post bloom, when there is a pause in the growth of the berry. Cluster samples should be taken at this time and weighed. When clusters are harvested in the fall, they will be 1.8 to 2.5 times their weight at lag phase. Taking these weights at lag phase and obtaining an accurate cluster count enables the winemaker to estimate the final crop per vine. It is then possible to extrapolate the final crop size based on vines per acre. Keeping records of this information for all vineyards and blocks makes it possible to accurately refine the multiplying factor more exactly over the years. If no record of actual lag phase and harvest weights is available from prior vintages, a factor of 2.1–2.2 times your current lag phase cluster weights is a relatively good predictor.
Late summer and early fall: veraison to harvest
Now we enter the season that demands and deserves the most attention from the winemaker. This is as true in the vineyard as it is in the cellar. As the clusters enter veraison, they give a direct indication of how consistent their ripening will be. The uniformity of veraison, as does uniformity during bloom, indicates a highly consistent ripeness. Veraison is easily observed and tracked in reds. With white varieties, changes in the berry are more subtle, and tracking it is of little practical use. For white varieties, the winemaker must rely on information gathered during bloom.
Some red varieties have aggressive or unpleasant flavors when underripe. With these, a thinning of laggard clusters at 80–90% veraison should routinely be considered.[11] Any substantial amounts of second crop should also be removed at veraison. With the exception of these light thinning passes, the winegrower should avoid operations at this time of year that remove material from the vine, such as leafing and hedging. The vine responds to these operations by slowing its metabolism for several days to a week afterwards, and this is highly undesirable during ripening. The vine should be left alone once ripening begins at veraison so that all of its energy can be directed without disruption toward producing color and flavor.
The vine needs access to moisture and nutrients during this period, and it is unwise to withhold them in the fallacious belief that moisture stress makes for better quality wine. The amounts provided should not be so large that the vine begins growing again, but if moisture is so lacking that basal leaves begin to senesce, wine quality will suffer.
The myriad decisions related to sampling and picking are addressed at the beginning of the forthcoming section on winemaking (Section III, Chapter 15).
Late fall and early winter: postharvest
As during every period of the year note should be taken of the conditions of the weather and vine postharvest. This is the period when the vine stores energy for the following season’s initial growth. If there are active leaves on the vine after harvesting, it is wise to apply some fertigation. You do not want to provide so much moisture and nutrients that the vine begins growing again—only just enough to keep the leaves active and on the vine. If the harvest is late and the leaves have largely senesced, this should be noted both for winter pruning decisions and for nutrient supply in the spring to come. Cover crops are typically sown this time of year. Once the vines have become dormant buds, can be dissected to get a preliminary idea of fruitfulness for the following season.
[1] In wine, as in politics and religion, there is no single correct way of thinking. I have my own personal view of how to make wine, but it is only one view. I believe deeply in my own approach. I try not to disparage differing viewpoints, regardless of how passionately I believe in my own. There is, after all, no morality of flavor or style.
[2] As one example of this approach in practice, let us say that the winemaker employs the formula of using 100% whole clusters in their Pinot Noir fermentations. However, the relative maturity of stem flavor varies from vintage to vintage. So, in vintages with less developed stems, the wines will show strong herbal or even herbaceous character. In vintages with more mature stem flavor, the spicy character of stems somewhat akin to cinnamon will be more evident.
[3] Using the same technique of whole cluster as in the example above, the targeted-style approach winemaker would begin with an ideal level of stem character in mind. Based on their understanding of the nature of the vintage and degree of ripeness of the stems, they would elect to use anywhere from zero up to 100% of the stems with the goal of creating consistent texture and flavor from this component each and every year.
[4] In my first year as a winemaker, I was taught a valuable lesson during this period. The harvest had just ended, and I was both accustomed to working every day and eager to continue. When I asked what we were doing next, Mike Richmond, my boss and mentor, replied, “Nothing,” and proceeded to explain the concept of benign neglect. Sometimes the wines want and need to be left alone. Not ignored—that would be dereliction. Rather, just observe them and let them rest for a while. Doing too much to the wines, especially early in their life, wears them out.
[5] For example, a long drawn-out bloom will create a vintage with a wide range of ripeness, while a compact bloom will lead to a vintage with greater uniformity of ripeness within and between clusters.
[6] Fully successful fertilization, which produces four seeds and maximum berry size, is not always the best outcome in all cases. Smaller berries have greater skin-to-juice ratios and can produce wines with greater color and flavor intensities. Seeds are major contributors to the tannin content of some red wines and not all wines benefit from this.
[7] The date of bloom is particularly important because the period from bloom to harvest is the least variable period of phenology in the vine. With some years of experience and detailed records, a winemaker can quite accurately extrapolate the date of harvest from the date of bloom.
[8] Variations in ripeness can be undesirable in some cases, as with Cabernet Sauvignon or Sauvignon Blanc, where less ripe fruit has an aggressively negative character. In other varieties, notably Pinot Noir, a range of ripeness may produce a more complex wine.
[9] It has been well established that the best time to adjust the crop level is immediately after set, especially if a significant amount of fruit needs to be removed. If only a small amount needs to be removed, this operation— especially in certain red varieties—can be postponed to late veraison.
[10] In a scenario where you have less crop than ideal, clusters should still be removed from very weak or small shoots. Fruit on these shoots does not ripen correctly, and each shoot is in essence its own ripening unit. In other words, ripening does not translocate from one shoot to another, so decisions on crop load should be made on a shoot-by-shoot basis.
[11] In all varieties the relative strength of underripe character is stronger than perfectly ripe or overripe character. While 10% overripe character in the fruit may be barely perceptible and add to complexity in the final wine, 10% underripe is almost always too much. In varieties that contain pyrazines, of course, the percentage of underripe must be kept to an absolute minimum, and some degree of veraison thinning should be practiced. The optimal amount of fruit thinned at this point varies enormously, depending on the specific circumstances. As mentioned previously, this thinning pass should not be employed for major adjustments to crop size, which should be undertaken post set.