The grape harvest takes center stage each season, capturing attention across social media and the news as the most anticipated and celebrated moment of the winegrowing year. However, the life of a vineyard in Rioja begins much earlier. Months before autumn arrives, as from winter, the vines are already preparing themselves through such important stages as pruning, budding, flowering, fruit set, veraison and ripening. All of them form the vegetative cycle of the vine and determine the outcome and quality of each harvest.
In each of these stages, the winegrower makes key decisions: how to prune, how much foliage to leave, how to manage the soil or when to harvest; always taking into account the climate of the area of Rioja where the vineyard is located, the type of soil and the wine style they are aiming for.
In this article, we will go through the vine cycle in Rioja season by season, explaining what happens in the plant, the work carried out in the vineyard and the risks that may arise. As we explained in the article "Rioja varieties you should know", not all grapes behave in the same way. Tempranillo, Garnacha, Graciano, or Viura respond differently to climate, ripening, and viticultural decisions, and these differences are subsequently reflected in the wine.
In winter, after the leaves have fallen, the vine goes into dormancy. From the outside, the vineyard looks asleep, but it is a crucial phase in the vine cycle in Rioja. The plant's reserves are concentrated in the trunk and roots, and the vine grower uses this period to prune the vines.
Pruning in Rioja consists of selecting the canes and spurs to be left for the following season and defining the bud load, i.e. how many potential new shoots the plant will have. This decision has a direct influence on the balance between production and quality: fewer buds usually means less quantity, but a better balance with healthier and more concentrated grapes, resulting in better quality.
In Rioja, different training systems are used, such as bush vines and trellised vines, adapted to the age of the vineyard, the variety and the climate of each zone. As we explained in the article "The three zones of Rioja: Alta, Alavesa and Oriental", these conditions can change considerably from one place to another. It is not the same to prune an old bush vine in a warm area, where the system helps to protect the grapes from excess sun, as it is to work a trellis on a northern slope, where the aim is to maximise sun exposure. Each environment determines how vine training and pruning are approached.
Pruning is strictly regulated in Rioja, especially concerning the number of buds: maximum 16 for white varieties, 14 for Garnacha and 12 for the rest of the red varieties. The aim is to control yields and guarantee quality.
At the end of winter, when temperatures start to rise, the sap starts to flow, traditionally known as the bleeding of the vine. This results in small drops of sap that appear in the pruning wounds. This phenomenon indicates that the plant is starting to reactivate after winter dormancy and that the new vegetative cycle is about to begin.
As temperatures rise, the vines awaken further and start to grow. Bud burst arrives: the buds swell, open and give rise to the first green shoots. This is the start of the new season. This usually takes place during the first part of March in the easternmost part of the Rioja Oriental, gradually spreading westwards throughout the whole of the appellation over the course of about a month.
During this stage, the vineyard is particularly sensitive to spring frosts. A single cold night can damage the young shoots and compromise the harvest, especially in cool areas or in plots at the bottom of the valley where cold air accumulates. The spring weather in Rioja can be very variable, so the winegrower needs to be vigilant and, in some areas, apply measures to reduce risks, such as the moderate use of sprinkler irrigation or management of the soil.
During the summer, the vineyard enters its phase of maximum vegetative growth, developing a large number of shoots, leaves and lateral buds. To control this growth and maintain the balance of the plant, the vine grower carries out different canopy management tasks, such as further shoot thinning and removal of lateral shoots, as well as deleafing. Shoot thinning consists of eliminating some of the main shoots to avoid excessively dense vegetation, similar to the removal of lateral shoots that grow on the main canes; and deleafing removes part of the leaves that surround the clusters.
These practices make it possible to regulate the vigour of the vine and achieve a better balance between vegetative development and fruit production, which is essential for obtaining higher quality grapes. A vine with excessive vigour allocates too many resources to the growth of leaves and shoots, generating shade and hindering the correct ripening of the bunches. On the other hand, a balanced canopy improves aeration and the entry of light, favouring a more homogeneous ripening and reducing the humidity inside the vine. This reduces the risk of fungal diseases such as mildew or botrytis and improves the health and quality of the grapes. However, an excess of foliage favours humid and shady environments, while too much leaf removal can overexpose the bunches and cause sunburn on the grapes.
Veraison occurs towards the end of summer and marks the beginning of grape ripening. The grapes change colour and begin to accumulate sugars, reduce acidity and develop their aromas. From veraison onwards, the winegrower precisely controls the state of health and the level of ripeness, including the evolution of the pulp, skin and pips.
The date of harvest in Rioja varies according to the area, the variety, the vintage and the style of wine. It usually begins towards the end of August for some white varieties and warmer plots in Rioja Oriental, and can last until the end of October or even early November in the cooler areas of Rioja Alta and Rioja Alavesa, where late-ripening varieties such as Graciano and Mazuelo are harvested later to reach optimum ripeness. Its timing is also influenced by weather conditions in the final stages of the season, as rainfall, temperature changes and the risk of autumn storms can all affect when grapes are picked
During this period, the Rioja Control Board carries out systematic sampling in its control vineyards in the different areas of Rioja, and publishes its ripening bulletins to guide winegrowers on the optimum time to harvest.
Manual work is still essential in Rioja. Pruning defines the starting point, shoot thinning selects the necessary shoots, deleafing controls exposure to the sun and canopy management ensures ventilation and balance. In addition to these tasks, hand harvesting is practised in large parts of the region, especially in high-quality and bush-trained vineyards, allowing for a more precise selection of the clusters at the optimum moment of ripeness.
Each variety responds differently to these decisions, something that is particularly noticeable in late-ripening examples such as Garnacha or Graciano. If you want to know more about each variety and understand what it contributes to the wine, you can explore the article "Rioja varieties you should know".
Soil management is a key tool in the Rioja vineyard, as it regulates vine vigour, controls erosion, and optimises water availability. Cover crop between rows is used strategically and varies according to the climate, the soil and the type of plot. In wet years or in more vigorous areas, it helps to limit excessive plant growth, improve soil structure and reduce compaction, although it can increase pressure from fungal diseases such as downy mildew if not managed properly. On the other hand, in dry years or in soils with low water reserves, its presence is reduced to avoid competition for water and minimise water stress in the vine. Soil management, together with water management, is essential for maintaining a balance between vegetative growth and production, and for promoting a more uniform and higher-quality ripening of the grapes.
The Rioja climate requires constant vigilance against fungal diseases such as powdery mildew, downy mildew and botrytis, the incidence of which varies according to the humidity, rainfall and ventilation of the vineyard. Powdery mildew develops especially in warm, dry conditions with poor aeration, affecting leaves and bunches and potentially affecting grape quality. Downy mildew, on the other hand, appears in wet and rainy springs, mainly damaging leaves and young shoots, which can weaken the plant and reduce yields. Botrytis tends to appear closer to ripening, in conditions of high humidity and poor ventilation, and can cause bunch rot. Balanced canopy management, together with appropriate fungal disease treatments, is key to reducing the pressure of these diseases and protecting the quality of the harvest.
In addition to spring frosts, other risks include heat waves, hail storms and prolonged drought. Each area of Rioja is affected differently, and some winegrowers even protect themselves by having vineyards in different sub-zones. For more information on these differences, you can consult the article "The three zones of Rioja: Alta, Alavesa and Oriental".
Rising temperatures bring forward bud break, veraison and harvest, and also cause a higher concentration of sugars and possible acidity imbalances. It also increases the risk of water stress and variability between vintages, with more frequent extreme events such as heat waves, droughts and storms. This makes it necessary to adjust vineyard practices, plot selection and canopy management to maintain the balance of the ripening cycle.
Among the measures being adopted are: later pruning, increased use of canopy cover, canopy management to balance sun and shade, selection of plots with higher altitude and cooler exposures, recovery of varieties better adapted to heat such as Garnacha or Mazuelo, and management techniques that preserve acidity and freshness.
To understand the vine cycle in Rioja is to understand where its aromas, balance and character come from. Every decision in the vineyard influences the final wine.
The Rioja Wine Diploma is the recommended starting point to continue learning about these processes. In addition, for alumni students who want to go a step further, the specialised course The Four Seasons of Rioja allows you to delve even deeper into the subject.