In an observation of wine shoppers in Australia, it was found that consumers spent an average of less than one minute in front of the shelf, a total of approximately four minutes browsing in the store and only a minority of shoppers spent up to 15 minutes buying wine (20). Less than one minute! Add to that the fact that wine buyers are overwhelmed by (read spoiled for) choice AND that they want to make a quick decision and convincing a consumer to choose your product over a neighbouring bottle becomes a daunting task.
The Cambridge Business Dictionary defines consumer preference as: ‘The fact of people liking or wanting one thing more than another.’ So how do you make someone like of want your product more than your competitor’s? One way of doing it is by using preference mapping.
Preference Mapping 101:
1. Firstly, a trained sensory panel describes a wine’s specific sensory characteristics and indicate the intensity of each of these characteristics, creating a sensory profile for each in a series of wines.
2. Secondly, a representative sample of target consumers evaluate the wine, give their opinion and indicate whether they like/dislike it, as well as which wines are preferred.
3. The final step is to link the consumer preference to the sensory description of the wine.
Preference mapping allows you to identify which wine characteristics are preferred by consumers and which consumers have similar like and dislikes, which in turn allows you to identify winemaking practices that can be manipulated in order to change the sensory attributes of a specific wine so that it is preferred by a set of consumers (21). Besides indicating whether they like a product or not, consumers can provide additional information which will allow segmentation of markets based on a variety of factors, e.g. age, demographical information, gender, wine knowledge etc. Marketing segmentation allows you to divide your target market into subsections of consumers that display similar traits, likings and wants, which means you can now optimise your promotional and advertising techniques to address the needs of a particular customer segment (22).
A previous study divided US consumers into four groups using their level of wine knowledge as a segmentation tool (23):
1. wine novice: just starting to experiment
2. wine interested: drinks wine occasionally; become more curious about product
3. wine lover: drinks considerable amount of wine; interested in learning more; knows a lot about wine
4. wine connoisseur: expert; enormous amount of knowledge about wine
The factors that influence the preference and purchase behaviour of consumers are distinctly different in the different segments. It has been shown that novice consumers are more influenced by the region of origin of a specific wine, independent of the type or brand, whereas an increase in wine knowledge and expertise results in a combination of product attributes becoming more important to the consumer (9). In addition, studies in the US have shown a positive correlation between wine knowledge and wine consumption: the more a consumer knows about the wine, the higher the consumption. Men also tend to have a higher level of subjective wine knowledge, which is important when taking into account that women are responsible for 80% of the wine purchased in the USA (17). To make matters easier, two thirds of wine drinkers in the USA use the internet to get information about wine and more than 50% of all wine drinkers are on Facebook, while 25% of these also use MySpace, YouTube and Twitter (24). So reaching a consumer with targeted product, promotional or marketing information is now just a mouse click or tweet away.
There are various factors that influence the purchase behaviour of a consumer segment, including physiological factors (motivation, personality, perception, learned customer behaviour, lifestyle, values, beliefs, attitudes) and socio-cultural factors (personal influence, reference groups, family influence, social class, culture and sub-culture) (17). So besides all of these factors that influence the customer in their purchase decision, what exactly goes though the mind of a consumer when they stand in front of a shelf lined with bottles of wine as far as the eye can see?
The five steps in the purchase decision process (17):
1. Problem recognition stage: the consumer observes a discrepancy between his/her ideal and actual situation and recognises a NEED. Ideally I would like to have a bottle of wine with dinner and I don’t have one.
2. The consumer searches for information to fill the need. This is done in two ways:
a) internal search of previous experiences with products/brands. I tried this wine last time and really enjoyed it.
b) external search for information: personal sources (advice from family/friends), public sources (consumer reports, government agencies), market sources (information from seller, advertising, company websites etc.). I remember a friend mentioning that this was a really great wine.
3. The consumer assesses the value by evaluating alternative products/brands with regards to both the objective and subjective attributes of the product. But this one has a prettier label and costs less than that one.
4. The purchase decision itself: after all alternatives in the consumers’ consideration set are evaluated, the consumer chooses to purchase the brand/product with the HIGHEST PERCEIVED VALUE. I think this bottle will go well with dinner and is not too expensive.
5. The post-purchase behaviour: the consumer evaluates the purchased item, comparing it with his/her expectations and decides whether he/she is satisfied or dissatisfied. This bottle of wine went well with dinner; I enjoyed it and will buy it again.
There are various product attributes that influence consumer preference (4). These can be classified as either being extrinsic or intrinsic to the product. Extrinsic attributes are external to the product. These are the attributes consumers use to search for a product and marketers most often use to influence consumers. These include wine type (red/white etc.), cultivar, producer, brand, country of origin, region of origin, price, alcohol level, vintage, medals and awards, environmentally friendly/organic, closure, capsule, bottle (shape, size and colour) and label (style, shape and colour). Intrinsic attributes are also known as ‘experience’ attributes which are only evaluated at consumption and associated with the physical characteristics of the wine itself. These include overall taste evaluation, acidity, tannin, sweetness, flavour, off-flavour, aftertaste and complexity (4). The extrinsic attributes will play a significant role in not only convincing a consumer to choose your wine, but also creates an expectation, whereas the intrinsic attributes will ensure that he/she comes back for more if that expectation was met.
It has been found that consumers who purchase larger quantities of wine and buy wine more often are significantly more influenced by the attributes of grape variety and origin of wine. In contrast, promotional display, attractive front label and brand name carry more weight to consumers who purchase smaller amounts of wine and do so less often (22). Of the most important factors including region of origin, quality, price and grape variety, one study found that the region of origin was the most important, with consumers willing to pay more for premium priced wines if they originated from a perceived higher quality wine production area. This study also found region of origin to be more important to women than men and that consumers who prefer red wine were more influenced by this attribute than white wine consumers (17). Similarly it was found that the country of origin, together with price, were the most important factors in wine evaluation, more so than the brand. The presumption that consumers infer a product’s quality from his/her stereotyped beliefs about the country of origin, is referred to as the ‘halo effect’, which results in the origin of the wine being perceived as an indicator of quality (27).
As far as visual cues are concerned, the bottle, colour of the glass, front and back label, capsule, bottle closure and wine case performs not only practical and technical functions, but also plays a role in aesthetics and evokes emotion in a consumer (17). As for the role of packaging in consumer preference, conflicting results have been found, probably due to the fact that the importance of these attributes differ between market segments. The label is the most important piece of communication between the consumer and the marketer and while the front label piques interest, the back label supplies information, of which the most important have been shown to be taste descriptors, winery history and food pairing suggestions (28). An Australian study found the presence of taste descriptors could increase the choice probability of a wine by as much as 7.4% (5). It was found that although 57% of consumers regularly read the back label, they have trouble matching the back description to the actual taste and aroma of the wine. It was found that simple descriptions are the most helpful (17), while unique, eye-catching and colourful features of a label are most desirable from an aesthetic point of view (23). The closure method had no effect on purchase intent, but it did influence the perceived quality. This is important because there is a direct correlation between the perceived quality of a product and how much a consumer is willing to pay for it (17). While a study in 2007 in Australia found label design and visual information to be of zero importance (respondents paid attention to brand, price, region, country of origin and medals), it was proposed that visual elements probably have a strong subliminal effect on wine choice even if consumers can’t articulate it (26). This is supported in a study where the perception and quality of wine differed significantly once the label was evaluated and the wine then tasted (23).
As far as the provision of shelf information is concerned, a study of 21 Shiraz wines in Australia in 2009 found that the presence of taste descriptions increase choice of the wine by 3.9 to 15.1%. When displaying critic scores or ratings, there was a 9.8% increase in choice when as expected the scores were higher, but also if the ratings are in higher agreement. When using a 5 star rating system, researchers saw an average increase if 3.5% in preference per increase in star rating (20).
There has been a tremendous amount of research done to try and figure out what influences a consumer to pick one bottle from a shelf instead of another. Australia is leading the pack with this type of research, providing valuable information as to what exactly it is that the consumer wants. As far as the preference of ‘Old World’ countries are concerned, studies in Italy, France and Spain indicate that ‘designation of origin’, ‘vintage’, ‘it’s matching food’ and ‘I read about it’ are considered to be the most important wine attributes when consumers select a wine. In contrast, preferred wine attributes by ‘New World’ wine consumers in Australia, New Zealand and United States include ‘grape variety’, country of origin’, ‘someone recommended it’ and ‘I tasted the wine previously’. Attributes including ‘brand name’, ‘label design’, ‘price’ and ‘it won a medal or award’ have similar relevance for consumers in both segments (11).
In Australia in 2007, a study looking at the preference of 740 consumers with regards to 16 attributes, showed that brand was the most important attribute when consumers displayed preference for a wine, followed by price, region of origin and medals or awards (4). In contrast, another Australian study in the same year, found higher loyalty towards price than any other attribute, including brand, region of origin or variety (17). So a consumer would rather choose a different brand or variety before buying a product in a different price category. As far as the provision of product information goes, consumers were more likely to choose Australian wines than American ones when provided with information about the wine regions or innovative wine production in Australia (6). In 2006 it was found that ‘someone recommending a wine’ and ‘having tasted it previously’ were key attributes to in determining consumer preference, while in=store promotion and information and attractive labels were least important (18).
An American consumer survey found that the segment of consumers that preferred sweet wines, were primarily female, young, adventurous, willing to try new wines, easily embarrassed when confronted by wine authority, wanted to be engaged and their confidence built in their wine preference and they need personalised advice on wine and food pairings. In contrast, consumers who preferred a more intense type of wine style, were more likely to be male, a little older, more confident in choosing wine and wine and food pairings, while preferring dry wines that are complex, balanced and full-bodied (10). With this knowledge you can now focus marketing efforts on the consumer segment that your particular wine appeals to.
In a study of Spanish consumers in 2011, ‘it is matching food’ was found to be the most important attribute, followed by designation of origin, then ‘I tasted it previously’, grape variety, and country of origin. Vintage and ‘someone recommended it’ were of less importance and brand name and ‘I read about it’ were found to be not at all important and as expected, label design was the least important attribute when consumers had to choose a wine. Price was found to be unimportant when consumers were selecting premium red wines, as they expected the price to be higher and as a result paid more attention to other attributes (11).
In 2008 it was found that direct, personal and sensorial experience are the most important attributes when consumers select a wine. Certain elements that influence the choice of consumers include attractiveness of label, variety of grapes, brand and region of origin. As expected, the impact of these attributes differ significantly depending on certain variables, of which involvement towards wine, frequency of consumption and geographical province seem to be the most influential (9).
Using a trained panel to generate sensory attributes for 6 Canadian wines combining it with the preference data of consumers, a research group was able to identify the drivers of liking for these wines, in other words, identify which sensory attributes are responsible for a consumer liking a specific wine. For the Chardonnay wine, fruity, spicy, vanilla and oak aromas were identified, while vanilla and oak characters were drivers of liking in two red wines. When wines were evaluated in a blind tasting, two groupings of sensory characteristics were identified. When additional information of the wines was provided, a third grouping was identified. This reveals that extrinsic cues can affect the sensory experience of a consumer (14).
In a study of the most influential attributes in different countries, including Australia, UK, China, Germany and Israel, ‘I tasted the wine previously’ and ‘someone recommended it’, were always amongst the top three most influential attributes (19). This means that promotional activities allowing consumers to experience your wine before purchase could significantly influence the buying potential of your wine.
As previously mentioned, the importance of these attributes differs among market segments. Two factors that play a significant role in segmenting consumer preference are gender and age.
Women: rate colours, images, pictures and logos higher than men
find black labels significantly more confusing, hard to read and too much information
consider wax seals an indication of freshness and foil coverings an indication of quality
more reliant on shelf information than men who read about wine at home (9)
prefer wine in medium price bracket ($10-14) while men favour %25+ bracket (17)
more consistent in wine choice whereas men are less prone to buy same wine twice (17)
Men: prefer to know significantly more about vintage and cultivar than women
favour red wine (17)
Consumers can also be segmented based on their age: traditionalists (born 1900-1944), Baby Boomers (born 1945-1964), Generation X (born 1965-1976) and Generation Y or Millennials (born 1977-2000). There are distinct differences between the purchasing behaviours of the different segments (17). Because consumers in the different segments drink wine for different reasons, a winemaker needs to understand the motivation of the consumer in order to adjust marketing strategies according to meet the desired requirements of each segment (17). While the Baby Boomers are the most significant segment in terms of purchase and consumption, Generation Y is emerging as an important segment due to their increasing buying power. This generation is growing up in a media-savvy, brand-conscious world, and an almost unlimited access to information, seeing as nearly 100% of Generation Y is connected to the Internet. This generation is displaying the largest increase in consumption compared to the other segments, making this a growing market with increasing market power (22).
Besides Generation Y that is being identified as an emerging market, China is a country ripe for the picking.
Due to the sheer size of the consumer base, estimated at an astonishing 200 million people, China has become a prime export target. Furthermore, the entry of China into the World Trade Organization implies drastic reductions in tax and tariffs. Even though exports to China are down, consumption figures are still on the increase, with a further increase of 54% predicted for the period of 2011 to 2015. Consumption is estimated at 300 million bottles of wine per year and nearly all red wine. As for the Chinese consumer, they prefer red wines with meals and the sweeter the better. Any arguments about the health benefits of wine are well-received and whereas everyday wine consumption is almost non-existent, the primary reason for purchase is gift-giving. Chinese consumers like to sample wines before they buy, prefer discount-stores, are impulsive buyers and have no knowledge on Chine food pairings with wine. Some of the more important drivers of liking for consumers include the price, where $10-15 per bottle is preferred, followed by the $5-10 range, prior knowledge of the wine or a recommendation, followed by in-store tastings (8). The country of origin is also very important for Chinese consumers. These consumers also prefer prestige/stately labels and show preference for brands featuring flowers, gold, animals, dragons or even cartoon characters.
While there is an absence of a wine culture in China, consumers still need and want more information pertaining to wine and health, wine etiquette and finding good value wines and the major sources of this information have been identified as consumer reports, newspaper columns and tasting experiences in-store (8). As for their taste in wine, consumers prefer sweet red wines with aromas of berries, plums and cherries, while strong wood characters are also appreciated. Preferred varieties include Cabernet Sauvignon, Merlot and Zinfandel, as well as wines with one powerful aroma, rather than a bouquet. It is important to target those consumers that are not afraid to try new wines and enjoy the diversity of choice (8). In order to enter this market, cellars will need to produce mid-range red wine that matches Chinese food, as well as pricier red wines in elaborate packaging to address the tradition of Chinese gift-giving. In addition, having Chinese people to promote you brand will overcome both the language and culture barriers.
The SA wine consumer
The consumption per capita in South Africa is still much lower than in other producing countries and by researching the purchasing behaviour of South African consumers, it is possible to improve and understand the South African wine market (17). The average South African consumer spends approximately R200 to R299.99 per month on wine, 50% consume 1 to 12 glasses of wine per month and spend an average of R25 to R49.99 on a bottle of wine. The majority (53%) prefer red wine, with variety (40%), price (20%), origin/brand (10%), word of mouth (10%), wine awards (5%) and packaging (2%) being the most important attributes when choosing a bottle of wine. Preferred points of sale include the cellar door, liquor stores and the supermarket. A consumer survey in 2010 found that there is correlation between the purchasing behaviour of South African consumers and demographic variables. Similar to other countries, males spend on average more on a bottle of wine and had a higher wine knowledge compared to females. More males favour red wines and natural cork and consumers are willing to pay more for a bottle of red wine than white (17).
The only way to ensure success in the market, be it domestic or foreign, is to understand consumer preferences for wine flavours and extrinsic factors that influence purchase behaviour, consumption and repeat purchase (14). It is possible to select suitable target markets with the appropriate knowledge of consumer segments and the wine origins they prefer (12). Quality, good value and variety seem to be the most important wine features, while brand, distribution, price and extrinsic factors are better predictors of sales that the sensory characteristics of the wine (6).
It is possible to measure flavour-related chemical compounds in wine, generate descriptors with a trained panel and generate like/dislike descriptors with a consumer panel and use this information to identify what descriptors are responsible for consumer-liking and the aroma compounds responsible for them (15).
Cheap wine. No, it’s not a swear word, although it is sometimes used as one in the wine industry. Cheap wine and nostalgia often go hand-in-hand, as one begins to reminisce about “the good old days”. Memories of late nights, good times, bad times, happy times and sad times may come flooding back to mind, and whether these memories make you smile or not, there is one important thing to remember: drinking cheap wine did not kill you!
Inexpensive wine is no new find to us students, we are all quite familiar with Bohemia’s two-for-one box wine specials, and it shouldn’t be an undiscovered treasure to the broader market either. Recently I have had to swallow my pride, and some very cheap wine, only to discover that cheap does not mean low quality, undrinkable nor unpalatable. Can you imagine my shock?
In fact, I was very pleasantly surprised to discover that most of the wines priced under R50 a bottle were of a pleasant and lively character. I know I may sound a bit pompous, but you probably know at least one or two avid wine consumers who also believe that cheaper wines are inferior to pricier wines. Initially I was very weary of my newly developed taste for cheaper wine, I wondered if perhaps it was just a phase that I was going through. Perhaps I had just developed a liking towards the ‘wine-style’. Then began the internal debate and finally a conclusion, “Cheap is not a wine style, Jenna”.
I have been led to believe that quality always trumps quantity and that it is incredibly difficult to achieve a quality wine in a large quantity. Bulk wine, another word us winos dislike, should not automatically be written off as wine of a poorer quality, nor should it readily be associated with cheap wine. Yes, it is true that most bulk wines are cheaper, however the quality cannot be judged unless one has actually taken a walk through the vineyard(s). It is often hard to believe, and easy to forget, that some of our box wines come from the very same block of grapes that various premium wines might.
Taking a glance at wine ranges, many consumers cannot understand why their R200 per bottle 2015 Cabernet Sauvignon is not as easy drinking as the R50 bottle, and here is where the stigma arises. Bulk wines and cheaper wines are not made to be kept on a shelf for 20 years, they are made for consumers to enjoy now. This does not make them poorer wines by any standards, however the winemaking behind these wine styles is a completely different ball game. These wines are made with the aim to sell as soon as possible, to meet consumer demands and to ensure that you are receiving the same product every time. Wineries would go bankrupt if they only produced 3 to 5-year barrel aged ultra-premium or reserve selection wines at R200+ per bottle.
Being a winemaking student, and telling winemakers as well as lecturers that you prefer a bottle of sweet, pink, carbonated bubbles to the finer, more complexed MCC is a no-no. Should this be something to look down on? NO. Each consumer has their own preferences and this is what makes the wine industry so diverse. It is very easy to forget that ‘expensive taste’ and ‘tasting expensive’ are two very different things.
It doesn’t matter if you enjoy a dryer than the desert white, a sweeter than honey suckle nectar rosè or a mixed berry fruit-salad red, you can almost always find a bottle of whatever tickles your fancy for less. Chances are, if someone had presented me with a very expensive wine and an incredibly cheap one, I wouldn’t be able to tell the difference between either’s prices based on their taste.
Cheap does not mean nasty, cheap means inexpensive. Wineries know that students, for example, would rather pay R25 for a beer (x3 or 4) than buy a bottle of wine, so they make various wine styles available to their consumers at a more affordable price. Personally, if I had to choose between paying R50 for a bottle of wine that I am familiar with, that is rock steady throughout the years and almost guaranteed to taste how I’d expect it to, over paying R25 per beer/cider, I’m going to choose the wine.
Another benefit of not turning my nose up to cheaper wine, is realising that paying corkage at a restaurant for a good wine (that I’ve paid much less for than the options on the menu), saves enough money to allow me to order dessert too!
If you find yourself on the fence about the idea of trying out something a little less expensive, grab a bottle or two of something that catches your attention the next time you go shopping and give it a try. Taste is subjective, the same wine won’t get a 10/10 rating from everyone sitting at the table drinking it, but if you enjoy it that’s all that matters. Try different brands too, that way you can build up a list of wines that you enjoy and know that you can readily pop/crack open the next time you’re craving a glass. I am by no means saying that you shouldn’t buy expensive wine, I’d still encourage it, but if you’re going to a braai, a girl’s night or a dinner party, grab a bottle of something cheaper in a similar style to the more expensive bottle you’ve been saving.
Introducing yourself to various wines is always a great idea, don’t get too hung up on how much the bottle costs or what others may think if you’re caught drinking a specific brand of wine. As long as you are enjoying what you are drinking and making more memories as you do, then who are we wine snobs to turn our noses up at a glass of wine merely because it’s cheaper? If it’s good, it’s good!
A darks screen appears. Slowly glimmers of light start to peak through to form a word – WINEMAKER. Gentle soothing music plays as we zoom out on the Earth. Then swiftly cut to a vineyard. Ladybugs fly happily. A cricket or two sings in between some bunches. All of a sudden the roar of quad bike disturbs the peace. The ecosystem is in pandemonium, a hand reaches into the canopy removes some grapes and then retreats. The quad bike disappears and the ecosystem recovers from the chaos and returns to its peaceful activities.
*David Attenborough voice starts* Winemakers. The world’s greatest profession. The only career on Earth to witness the full majesty of fermentation. There is much more here than we ever imagined.*Cut to shot of David Attenborough standing in barrel storage* I am standing right where the winemaker would taste his vintage wines for the first time each year. To the north of me is the bottling line. To the west is the tasting room. Behind me is the most exciting place of all – the cellar. From the shiny fermentation tanks to the cool barrel store – rarely seen places and untold stories. There’s nowhere in the world where wildlife puts on a greater show. This is the last place on earth where you can come eye to eye with the greatest animals that walk our planet. This is the winemaker.
Today we delve into the habitat and life of a wild creature that roams our land. From exotic locations like Australia and California, from France to South Africa this creature has been moulded and developed wherever the climate permits. The results of convergent evolution have never before been as evident as with the winemaker.
Let’s start by identifying a winemaker in the wild – there are a few key characteristics to look out for. The easiest way is to look at the feet, typically a winemaker will be wearing a pair of practical sturdy boots – waterproof and preferably dark brown colour to hide any red wine or chemical staining. In the winter it more difficult to find a winemaker, you need to have a keen eye to find the small giveaway details, jeans or khaki pants equipped with a tank sample key or the faint smell of wine in their clothes.
In the summer it is far easier to identify a winemaker. A tell-tale sign you’ve encountered a one is to look at their hands , if it is stained red and covered with cuts, blisters and plasters then you know you have stumbled across one. During the summer time the winemaker always smells like yeast and sugary grape must. They have shred the excess winter weight during a natural phenomenon called “harvest bod”. They need to do this in order to be nimble and quick during harvest ; climbing presses, fitting between barrels and cleaning out tanks. In addition to this it is also necessary for the winemaker to look at its prime to prevent their mate from leaving them in this period – the lack of attention the winemaker’s mate experiences during this time causes tension in the relationship.
The natural habitat of the winemaker varies slightly from winemaker to winemaker but they all live in an environment with one common factor – a cellar. The cellar is the building which a winemaker may spend up to 70% of the time. The other 30% is spent between the vineyard, the local watering hole and their residing area.
The diet of the winemaker, like most wild animals, is dependent on the season. In the cooler months of winter the winemaker needs to form a layer of padding to survive the harsh conditions of the cold barrel storage room and the icy cellar. This is done through a high consumption of red wine and braaivleis; for the South African winemaker only, other winemakers may feast on barbeque foods. As the warmer months approach and the commotion of harvest starts the winemaker survives off shots of grappa and coffee in the morning hours and then progresses to wine and ends off each day with a cold beer to be drunk with their wolf pack namely the assistant winemaker and interns.
Now, we have explored the habitat and the habits of the winemaker. Their wild ways are less of a mystery and another one of Earth’s great wonders has been illuminated. The next time you encounter a winemaker in the wild – do not be scared. During summer or as they call it “harvest” the winemaker may be irritable and snappy due to lack of sleep and stress but they can be tamed with good wine and company. While in the winter they are more approachable and appreciate any distraction from their life of filtering and bottling.
By Bryan Hed from Wine & Grapes U.
Since the new year was ushered in we have had several scary moments when Mother Nature unleashed an “excess of personality.” I’m referring to the cold weather events we experienced around January 1, 7, and 14, when temperatures slipped down below zero in many places across Pennsylvania, even in some south central parts of the state. As many of you might remember, the last time we saw below zero temperatures that far south (February from hell, 2015) primary bud damage was widespread and grapevine trunks in vineyards all over Pennsylvania (and certainly other parts of the Northeast) exploded in crown gall the following spring. This generated a two-year trunk renewal process that we’ve only just recovered from. Therefore, this may be a good time to review grapevine winter hardiness and the factors that affect it, as well as how we can prepare for possible remediation pruning and renewal this spring.
Now I don’t want to raise alarm bells just yet, as the conditions we’ve experienced this January haven’t been as horrific as February of 2015. But it’s always good to be prepared for any potential consequences, like bud loss and trunk damage, so we can anticipate altering our winter pruning plans and production practices this season.
Let’s start with a review of the temperature stats available to everyone on the NEWA website (newa.cornell.edu) and see just how cold it got in various places across the state during the first half of January. In the table below, I’ve listed low temperatures for January 1, 7, and 14 for many of the NEWA locations. Starting at northeastern PA and moving counterclockwise to swing back up into northern New Jersey and finally western New York, we get the following data (Table 1).
Areas of southeastern and northwestern Pennsylvania, at opposite corners of the state, appear to have escaped the below-zero temperatures for the most part, but some areas of south central Pennsylvania took a hit (look at York Springs). Areas of southwestern Pennsylvania experienced some of the most extended periods of below-zero weather, and parts of northeastern and central Pennsylvania also got quite cold. The temperature low is the most important bit to consider when sizing up vine bud damage, but the duration of those lows can affect the extent of trunk damage, especially in big old trunks where it may take longer for the core to reach ambient temperatures. Up in the northwestern corner of the state, the buffering effect of Lake Erie probably played a role in our relatively mild temperatures during that period, and we expect little to no damage to most of our vines as our wine industry there is heavily invested in tougher hybrids. The Erie area was also blessed(?) with a heap of snow (10 feet!) before the cold snap that provided added protection to bud unions of grafted vines.
If you’re anticipating primary bud damage, here’s a review of the ranges of temperatures for the LT50 (low temperature at which 50% of primary buds fail to survive) for the cultivars you’re growing. For Vitis vinifera, the LT50 range of the most winter sensitive cultivars falls between 5o and -5oF. This includes cultivars like Merlot and Syrah. But for most cultivars of V. vinifera, LT50 values fall more in the 0o to -8oF range (Chardonnay, Cabernet Sauvignon, Pinot gris, Pinot noir, Gewurztraminer). And finally, there’s the tougher V. vinifera and sensitive hybrids that have buds with LT50 values of -5o to -10oF. This includes cultivars like Riesling, Cabernet franc, Lemberger, and Chambourcin. On the flip side, most hybrids fall into the -10o to -15oF range (which is why Northeastern U.S. vineyards are perhaps still more invested in hybrids than V. vinifera). Then there are the V. labrusca (Concord) and the Minnesota hybrids that range from -15o down to -30oF for cultivars like Frontenac and LaCrescent. Unfortunately, we don’t have such helpful ranges for determining trunk damage, which often comes with more profound consequences and is costlier to address.
Rapid temperature drops are often the most devastating in terms of the extent of damage. Fortunately, December temperatures this winter descended very gradually giving vines time to fully acclimate to cold weather extremes. In fact, recent data from the Cornell research group in the Finger Lakes region of New York shows that LT50 values for primary buds of several cultivars were close to, or at, maximum hardiness. Therefore, it is hoped that many Northeastern U.S. vineyards were well prepped and close to their hardiest when these cold events occurred. On the other hand, any given cultivar in central New York is likely to be a bit more cold hardy than that same cultivar growing in southern Pennsylvania, simply because vines farther north will have accumulated more cooling units than those farther south. So there is the possibility of bud and—worse yet—trunk damage in parts of PA, to the more sensitive cultivars of V. vinifera.
We also had a balmy warm period during the second week in January that pumped temperatures up into the 60s in some places before plunging back down into single digits. However, it’s unlikely the brief warm period was long enough to cause any deacclimation of vines before cold temperatures resumed, and little, if any harm, is expected from that event.
The capacity for cold hardiness is mostly determined by genetics. As I alluded to above, V. vinifera cultivars are generally the most sensitive to cold winter temperature extremes, French hybrids are generally hardier, and native V. labrusca cultivars are often the toughest. Nevertheless, other site specific factors can come into play to affect cold hardiness, and this is often the reason for the range in the LT50 values. For example, there’s vine health to consider; vines that finished the season with relatively disease-free canopies and balanced crop levels can be expected to be hardier (within their genetic range) than vines that were over-cropped and/or heavily diseased. At times like these, we can’t emphasize enough how important it is to maintain your vines and production strategy with a view to optimizing their chances of surviving every winter. Other stresses like drought or flooded soils (during the growing season) that we can’t do much to control, and infection by leafroll viruses, can also play a significant role in reducing vine cold hardiness.
If you suspect damage, you should delay winter pruning of your vines, according to Dr. Michela Centinari. Feel free to revisit her previous blog posts and others at psuwineandgrapes.wordpress.com. Type “cold hardiness” or “winter injury” into the search box, and you’ll quickly and easily gain access to several timely blogs.
Bud damage can be estimated from 100 nodes collected from each potentially compromised vineyard block. Typically, gather ten, 10-node canes from each area, but do not sample from blocks randomly, unless the block is relatively uniform. If a block is made up of pronounced low and high areas (or some other site feature that would affect vine health and bud survival) make sure you sample from those areas separately as they will likely have experienced different temperature lows (Zabadal et al. 2007). You may find that vines in high areas need no or less special pruning consideration than vines in low areas that suffered more primary bud damage and will require increased remediation.
Once you have your sample, bring the canes inside to warm up a bit and make cuts (with a razor blade) through the cross section of the bud to reveal the health (bright green) or death (brown) of primary, secondary, and tertiary buds. You’ll need a magnifying glass to make this determination as you examine each bud. You should figure that primaries will contribute two thirds of your crop and secondaries, one third when considering how many “extra” buds to leave during pruning. And remember that some bud damage, up to 15% or so, is normal. If you’ve lost a third of your primaries, leave a third more nodes as you do your dormant pruning. If you’ve lost half your primaries, double the nodes you leave, and so on. However, when bud mortality is very high (more than half the primary buds are dead), it may not be cost effective to do any dormant pruning as it is likely there are more sinister consequences afoot, like severe trunk damage that is much harder to quantify. A “wait and see” strategy, or at least very minimal pruning, may be best for severely injured vines (Figure 1) and trunk damage will manifest itself in spring by generating excessive sucker growth (Figure 2). And one more thing: Secondary buds are often more hardy than primaries, may have survived to a larger extent, and in some cultivars, can be incredibly fruitful. This is especially true of some hybrid varieties like DeChaunac. So, to make more informed decisions when winter damage is suspected, you have to know the fruitful potential of your cultivar; and in cases where primary bud mortality is high, it’s therefore important to also assess the mortality of secondary buds.
Another great fear is the appearance of crown gall, mainly at the base of trunks. This disease is caused by a bacterium that lives in the vine. However, the bacterium generally doesn’t cause gall formation on trunks until some injury occurs, usually from severe winter cold damage near the soil line or just above grafts on grafted vines (if you hilled over the grafts last fall). Another search at psuwineandgrapes.wordpress.com will bring up information on how to deal with this disease. You can also visit What we have learned about crown gall for an update on research into this disease from Dr. Tom Burr and his research group at Cornell University. Tom has devoted a lifetime to researching grape crown gall and many advances have been made over the years. But it’s still a huge problem for Northeastern U.S. grape growers; and crown gall problems will likely increase as our industry becomes more and more heavily invested in the most susceptible cultivars of V. vinifera.
With more sensitive detection methods, Tom’s group is getting us closer and closer to crown gall-free mother vines and planting stock, but they’re also discovering that the crown gall bacterium is everywhere grapevines are located. Not restricted to internal grapevine tissues; it’s also found on external surfaces of cultivated and wild grapevines. So, clean planting stock may still acquire the pathogen internally down the road and management of crown gall, once vines are infected, will continue to be an important part of life in any vineyard that experiences cold winter temperature extremes. However, there is potential for a commercial product that inhibits gall formation, which can be applied to infected vines. The product is actually a non-gall-forming, non-root-necrotizing version of the crown gall bacterium that is applied to grape wounds and inhibits the gall-forming characteristic of the pathogenic strains of the bacterium. This product is still under development in lab and greenhouse tests, awaiting field nursery trials soon.
If you do happen to meet up with some crown gall development this spring, galled trunks can be nursed through the 2018 season to produce at least a partial crop while you train up suckers (from below the galls) as renewal trunks. When our Chancellor vineyard was struck with widespread crown gall in the 2015 season, we were able to harvest a couple of decent sized crops while trunk renewal was taking place (Figure 2), and we never went a single season without some crop. There’s also the issue of crop insurance to think of; adjusters may want you to leave damaged trunks in place so they can more accurately document the economic damage from winter cold.
Lastly, a great guide to grapevine winter cold damage was published about 10 years ago by several experts. In fact, information from that guide was used in composing large parts of this blog and I highly recommend you read it. It’s an excellent publication, the result of many years of outstanding research by a number of leading scientists and extension specialists from all over the Northeastern U.S. The details of that publication are found below and you can purchase a hard copy for 15 bucksby clicking here: Winter Injury to Grapevines and Methods of Protection (E2930).