Trained in Vain
(Originally published February 2008)
Gonna riff once more on a topic related to global warming. It’s pretty basic common sense that one cannot simply move a vineyard because its environmental conditions are changing. Or, more precisely put, the conditions are becoming less predictable. Less predictable because global “warming” is not a phenomenon which uniformly brings warmer temperatures. It is more accurate to say that it brings more erratic weather, more highs and lows and unexpected storms, droughts, etc. It’s not simply reducible to saying that a vineyard which once averaged daytime highs of 78 degrees now averages daytime highs of 82 degrees. More complex than that. Playa.
So, just as one cannot move a vineyard in its entirety to a spot closer to what once was the vineyard’s climatic norm, so too one cannot just rip up parts of the vineyard and replant them to better match evolving weather conditions. What, you can rip up the vineyard! Dag. However, vineyard reconfiguration is risky and, more importantly, expensive. Overall production numbers would drop, older and more mature vines would be replaced by younger vines, and there’s no guarantee that the new set-up would be an improvement over the former. What can a vineyard manager do?
To get closer to an answer we need to understand a wee bit about vine training and trellising as well as the vineyard technique called canopy management. All three aspects of growing a grapevine have changed substantially over past decades. Why, almost as radically as weather patterns are changing now.
Grapevines don’t grow all wild like, they are intentionally forced to grow in certain patterns and along certain paths. Once they have been forced into growing a certain way over a period of years the maturing vine gets pretty much “frozen” into this shape. To “unfreeze” a grapevine means pruning it back, most likely severely, to reestablish it into a new growth shape. Which means getting rid of the most productive parts of the vine and losing years of growth. No one wants to do that. Not even George Bush.
Grapevines fall down. And they can’t get up. So, just as with any type of vine, a support system needs to be provided for the vines to cling to and grow along. Contemporary viticultural practices use a system of stacks and wires to support the grapevines. These are called trellises. As one might expect the format of the trellising system will conform to the shape the vineyard manager desires in the grapevines themselves. This is called the training system because the vines are being “trained” to grow in a certain fashion.
The general concern in training and trellising grapevines is to control yields and ripeness. The vineyard manager broadly put wants to either maximize yields and make more dinero or reduce yields to produce fewer grape bunches of higher ripeness and flavor intensity. Depends on the end goal, sell a lot of wine or sell less wine (at a higher price). Different systems will favor differing goals. One will want to control sunlight exposure, both in terms of direct sunlight and length of sunlight exposure. One also needs to control the amount of photosynthesis the vines accomplish, the end result being a vine neither too vigorous nor insufficiently vigorous. This with one eye on where the energy and fuel is being expended — on grapes, leaves, vine shoots, roots, etc.
A number of factors come into play in deciding which trellising and training systems to use. General temperatures (both day and night), wind conditions, inclines in the vineyard, how the vines will face the trajectory of the sun through the day, how poor or rich the soil is, the kind of rootstock used with the grapevine, what type of irrigation one uses (if any), what type of trees, bushes or vegetation exists in the vineyard, and then what kind of grape is being cultivated with a focus on this grape’s normal ripening history (early/late, easily/with difficulty, etc.). Some trellising systems are more popular than others but none is 100% correct or incorrect.
As scintillating as the possibility is, Hanes will not exhaustively list all the different types of trellising systems. But, as illustrative examples, there are the following. Note that almost all vineyards use plastic or metal stakes and metal wires regardless of orientation because one does not want to use organic matter which may then house microbes or other nasty shit which could infect the vines.
Spur training is one way of doing things. It seems this is the easiest way of pruning the vine and requires the least amount of routine maintenance. The basic concept here is pare the growth back close to the base of the vine (called the cordon) as it comes out of the thick trunk which leads to the earth. There’s a fruit bearing vine length (called the cane) coming out of a thick knob formed on the cordon (called the spur). There are cut off together, as is another mature fruit bearing cane just beyond the spur. The cut point on the latter comes above two cane nodes. Out of these nodes in the next spring will grow the two canes which will bear fruit that season. And the spur grows larger as older wood accrues. Over time the cordon acquires many spurs along its length yet growth is kept as “close to home” as possible by managing the number of nodes which can grow the next season. A base trunk will generally support 2-4 cordons. Apparently this form of training and pruning is popular because it clearly separates spurs and their canes from each other and allows mechanical harvesting to capture more grape bunches without damaging the grapes or the vines themselves. And, later, allows for mechanical pruning for the winter.
Cane training is another way of doing things. The basic concept here is to keep cutting away older canes in favor of younger canes. Too many canes coming out of the cordon diffuses the energy during the next year’s growing season. Instead of cutting back all the way to the spur and retaining growth from the spur, here you pick the cane or two along the vine outside the spur that has loads of tasty buds and cut away the growth which just bore fruit that season so that the remaining canes after pruning are lean and mean and ready to focus come springtime. The canes left for the next growing season always have a good year of age on them to help produce new fruit bearing canes. The extra maturity avoids depending on purely new growth for fruiting and basically “rotates” fruit bearing among canes of various maturities without growing the canes too far from the cordon. Cane training requires more manual labor and cannot be mechanized. It presents the advantage of treating each cordon individually and making specific decisions about which canes to cut or keep. Deep thoughts.
In general, a third method called gobelet training may be employed. This is an older method of doing things and not so in fashion. The trunk of the vine is kept short and squat and the pruning done so close to the trunk that really there are not so much “cordons” coming out of it but just a wealth of “spurs” accumulated around the trunk. The vines tend to grow into a “goblet” shape this way and that’s what it looks like during the winter without foliage. The new canes, leaves and grape bunches all grow within this goblet, creating the appearance of a bush more than extended vine. As many note, this is why these are also called “bush vines.” Empiricism at work.
Again, without getting too technical, vine training segues to vine trellising might quick like. Vines trained in the gobelet manner rarely need stakes or wires as they derive full support from the thick cordons/spurs which form the goblet-like structure. Vines trained along the spur or cane methods may or may not prove favorable to particular trellising systems. As a result, discussing popular trellising systems explains further how the choices made in structuring the entire vine from trunk to grape bunch may need to change over the years to come.
Training establishes the foundation of how budding will occur and foliage start to come to life. But trellising is the part which makes the final determination. This will help decide how many grape bunches will begin to grow in the early part of the growing season and how the grapes interact with the new foliage. This in turn will factor into overall vine stress (i.e., how much work the vines will have to do along with how much energy and fuel the vines will take in). Vine stress remains a key factor in determining both the quantity and quality of the grapes which live to maturity and picking.
As stated previously, changes in weather, lots of ups and downs and sideway jags, have a direct impact on the grapes. The vineyard manager will employ years of experience and history to grapple with any climatic changes as they occur (she will also grapple with how much money the vineyard owner wants out of this vintage’s crop). Trellising the new growth along stakes and wires separates the new canes and with them the new foliage and then grape bunches. How they are separated and positioned will dictate how sunlight effects the vine and its component parts: the sunlight’s angle, duration, intensity, ability to reach below the foliage of top trellis, ability to touch the grapes directly, etc.
The posts themselves are normally spaced about 18 feet apart or roughly every three plants. Wires are then run the posts from end to end. How many wires depends on what kind of trellising system one wants. The wires have to be very taut and capable of holding substantial weight. If you think your neighbor is stealing your grapes, use barbed wire.
The most basic way of trellising the vines is to have two main cordons coming off the trunk in opposite directions along the wire. With a single wire placed about five to six feet above the ground, you just let the fruit bearing vines hang downwards from the wire. Simple enough. If the rows of vines are spaced adequately apart there will be ample room for sunlight to reach from the six foot high wire level all the way down to the earth and provide the necessary light coverage. As the foliage curtain thickens the sort of trellising has the advantage of shading the earth itself which may help the soil retain moisture if there’s no natural ground covering. Pruning can be done anywhere desired along the cordon(s) and their yearly growth.
If this strikes you as too lazy, there’s a way to provide greater structure to the vines and ensure more consistent separation as well as exposure to light. As in the former example, there’s a wire along which the cordons travel. This will be the bottommost wire, about three feet off the ground. Above this wire will be three to four other wires. The young vines are trained upwards across these wires (sometimes tied to them to ensure proper alignment). This trellising system takes few chances of missing sunlight and provides better air circulation. It also makes manual thinning and positioning easier as there’s ample support and room to work with each individual vine.
Another way of doing things is a sort of hybrid of the two former methods. Here there are four cordons growing off the trunk, two in each direction. The two on each respective side are positioned far apart, the bottom one three feet from the ground and the top one six feet from the ground. Then the vines and foliage hang down from these four cordons trained along two wires. For vineyard managers who favor the first method but see drawbacks in too much foliage density or lack of circulation, this method more or less halves those problems by spreading the growth out and requiring the plant to expend its energy in more controllable quarters rather than halves.
Naturally, some clever folks decided that this last method could be improved upon. What you do is take the four cordons, and instead grow them close together and then train vines up from the top cordon pair and down from the bottom cordon pair, using wires for training throughout. This seems like overkill but some folks say it’s the best way to reduce foliage density without necessarily reducing the quantity of leaves producing energy via photosynthesis. Why not?
Again, there’s lots of ways to structure the fruit bearing and non-bearing portions of the vine and they all work together to achieve a desired goal. In recent decades this goal has been to increase grape ripeness as much as possible with an eye on creating more concentrated, fruit-driven wines. The last important aspect of choosing a mode of vine training and trellising remains the capacity for canopy management. This is the science/black art of controlling the quantity and quality of general foliage as well as buds and grape bunches. In essence, the choices of vine training and trellising are made to enable the final degree of canopy management desired.
Vine “stress” is a good thing to many folks because a stressed vine will focus its energy into reproduction rather than general growth. This is a base effort to simply survive, not thrive per se. How does a grapevine reproduce? Duh, through grapes and the seeds inside them. Evil humans, though, fake out the grapevines by snatching the grapes to make wine and the dumb grapevines never figure this out, year after year. The more energy the plant puts into the creation and health of the grapes, the tastier the grapes will be for the purpose of making wine. No one needs a zillion healthy leaves and just a few grape bunches. We want healthier grape bunches and screw the leaves.
Canopy management, like other vineyard techniques or factors, controls the stress. This is similar to having too much water for the vines. If a vine’s roots have to work hard to dig deep for water this produces stress. The vine works on creating deeper roots rather than excess foliage. Energy not expended on finding water goes to the grapes so the plant can seed and survive. This is why the amount of water provided to the grapevine is often controlled vigorously by the vineyard manager. Same for the foliage or “canopy.” The quantity of leaves and vines will effect the quality of the grapes and must be micromanaged.
If the leaves block too much sun from directly hitting the grapes and ripen them, they gotta go. If the leaves prevent air circulation and contribute to the potential formation of mildew or fungi, they gotta go. If grape bunches are forming, any young vine material present without fruit they, you guessed it, gotta go.
By the same token, canopy management also can be said to include what is called “dropping fruit.” This is the process of selecting the healthiest, best positioned grape bunches along the vines and cutting off the remainder of the bunches. This forces the plant to refocus its energy on the remaining fruit alone, pumping them full of energy and love.
That’s basically what vine training, trellising and canopy management are meant to achieve. And it’s how we get bigger, bolder, juicier wines. Which cost a lot more money because all this manual labor gets expensive. And this is important for understanding how these vineyard techniques play out practically in the full spectrum of wine production and consumption. A lot of time and money go into these decisions. A lot of time. And money. It takes years to figure out which training and trellising system works best for which grapes in which vineyard (or section of a vineyard, etc.). And canopy management decisions can only be made based on the initial selection of the vine training and trellising. If the climate changes dramatically enough, this initial selection of vine training and trellising may have to be revisited. Which means money lost through vine restructuring and resultant lack of product grown in the interim.
Climatic changes that effect the world on the levels of continents, countries, regions or towns also effect the “microclimates” of vineyards and, further yet, the “micro-microclimates” of the vines themselves. Vineyard management is heavily tied up in controlling the environment of each specific plant and vine. If global warming changes global weather patterns it also effects the “micro-microclimates.” As said before, it’s not just warming per se. It’s the haphazardness of contemporary weather which imperils the choices made in vine training and trellising and then canopy management. Things that worked just a couple of vintages ago may not work anymore. Hell, things that worked three weeks ago may not work anymore. If this is so, these might be some results.
Training and trellising methods which today obtain desirable exposure to sunlight, air circulation and general vine stress may turn out to not be so desirable anymore. Which means more than just deciding between spur training or cane training, it means cutting it all back to the trunk to try new approaches. Shucks, perhaps entirely new approaches. Or ripping up vines entirely to plant new grape cultivars which will thrive better in the new climate. In terms of canopy management pulling leaves may result in more sunlight exposure for grapes but maybe less protective coverage for the grapes should there be late season “freakish” droughts, frosts or hailstorms. Changes in wind patterns may require repositioning of vine rows. If a vineyard does not cool down as much at night as in the past and thus give the vines time to rest, more leafy foliage might be required to shade the ground and prevent heat absorption, regardless of its effect on the grapes. A lot more overall cautiousness and hedging of bets may be required. Which will make “consistency of product” harder to achieve.
And all of these potential changes have a domino effect on whether or not mechanical harvesting or other automated vineyard activities may be employed, creating pressure on profitability and/or a rise in wholesale grape and then wine prices. Are vineyard owners and managers brainstorming about what they are going to do as weather becomes more unpredictable? Hanes doesn’t know, he rarely comes out of the basement. But it’s a legitimate question to ask. If the wine industry gets caught with its pants down because it cannot swiftly and easily change its vine training, trellising and canopy management practices it’s going to be the consumer who ends up paying for it. Someone call Helen Turley and Michel Rolland NOW!