The growing season (also called vegetation phase or growing season) is the rhythmically repeated part of the year in which a plant actively grows and develops. The study of the biological processes associated with this is called phenology. In viticulture, the vegetation period is the period from the last frost (late frost) in spring to the first frost (early frost) in autumn. This should last at least 180 days. The remaining part of the year in which a perennial plant does not grow is known as the vegetative dormancy, dormancy or rest period. The total of the annually recurring growth phases of a plant, including dormancy, is the growing cycle. In viticulture, however, the vegetative cycle of the vine is also often understood as a period without dormancy
The months or periods indicated in the table below for the various cycles of the vine are averages and the range of variation may be relatively wide. Possible influencing factors are environmental conditions such as climate (microclimate), weather, as well as soil characteristics and environmental conditions such as vine enemies. The period or the speed of development also depends strongly on the grape variety. Very early ripening varieties go through the cycle from budding to maturation (ripening) very quickly in around 130 days and are therefore suitable for cooler wine-growing regions. Late ripening varieties such as Riesling and Grüner Veltliner need more light and warmth, they have a long growing cycle of up to 200 days (see under Ripening time). Last but not least, the work of the winegrower in the vineyard has an effect.
The annual cycle of the vine begins after pruning in winter with the budding of the buds in spring and ends with the leaf fall in late autumn. A multitude of complex biochemical processes take place in the organs of the vine. The grape harvest should take place at the optimum ripening stage of the grapes. This ideal state is also known as physiological ripeness. The period from blossoming to grape harvest is estimated to be around 100 days, although this depends greatly on the grape variety and other factors.
|Budding||-||March - April||September - October|
|Flowering||8 days||May - June||November - December|
|Fruit set||-||June - July||December - January|
|Véraison (start of ripening)||-||August||February|
|-||August - October||February - April|
|Commitment||End of maturation||-||-|
|Leaf fall||-||November - December||May - June|
|Hibernation||3 months||December - February||June - August|
An ideal vegetation cycle in Germany and Austria(wine-growing zones A and B) runs as follows: After flowering as early as possible, the grapes should be exposed to moderate warmth and sufficient moisture from the time the fruit sets. A hillside location with at best vertical exposure (solar radiation) and the proximity of water bodies (seas, lakes, rivers) have a very positive effect. From the season onwards, sunny, warm but not too hot weather is an advantage. A long, warm but not too dry autumn promotes the storage of sugar during the day, and cool nights promote the formation of acids. It should not rain before and during the grape harvest.
A very vivid video (click to watch) about the annual vegetation cycle of the vine with all stages can be seen on YouTube using the example of the Moselle pole education(single pole education). The nine pictures show the entire process from winter to autumn (1 to 7: © Weinhof / Gästehaus Edgar Hermes).
The individual phases of the vegetation cycle are described in detail in separate keywords (see table above). With regard to the optimum or recommended time of application of fertiliser and plant protection measures, the so-called BBCH code was developed. The BBCH scale corresponds to the vegetation cycle of a plant. The climatic changes that have been felt worldwide since the 1980s will also have a very strong impact on the vegetation cycle and viticulture. These are explained under the heading of climate change.
The criteria for the suitability of a region for wine-growing are referred to as wine-growing eligibility. A list of relevant keywords on the subject of grape variety can be found under Grapevine, a complete list of all work and procedures in the vineyard within the vegetation cycle under Vineyard Care and a list of the various procedures relating to organic farming under Organic Viticulture.