Factors that influence grape production
- geography (latitude, elevation, etc)
- climate
- aspect (direction vineyards face)
- soil
- grapes (whether they’re allowed to be planted or suit the climate/soil)
- viticultural practices
- harvest
- annual weather patterns
- terroir
- regional wine laws + regulations
- history of region’s grape growing + winemaking
Considerations that should be made when establishing a new vineyard
- environmental + climate considerations
- trade + regional considerations
- grape varietals best suited
Difference between climate and weather
Climate is what you expect; Weather is what you get
Majority of the world’s vineyards are located between these two of earth’s latitudes
30* - 50* north and south of the equator in the northern and southern hemispheres
Macroclimate
refers to the climate of a region
Mesoclimate
refers to the climate of a village, a cluster of vineyards on a slope, or a particular vineyard
Microclimate
refers to the climate of a single vineyard or even the climate within the vines or around the canopy
4 major climates of winegrowing regions
- Continental
- Maritime
- Mediterranean
- High Desert
Continental climate definition
- has climate extremes: hot summers and cold winters
- tend to be interior regions
- northern Rhone and Ribera del Duero are good examples
Maritime climate definition
- are influenced large bodies of water and have warm summers and mild winters with rain falling year-round
- Bordeaux and Rias Baixas are good examples
Mediterranean climate definition
- have very warm, dry summers and cool, rainy winters
- usually near or around coastlines
- Southern Rhone and McLaren Vale are good examples
High Desert climate definition
- are hot and arid, particularly during the day, with temperatures plummeting at night
- Leona Valley AVA (CA) and Cochise County, AZ are good examples
Temperature descriptors used to further characterize the 4 major climates
- Cool
- Moderate
- Warm
- Hot
- Tropical/Humid
Diurnal shift definition
the difference between the average daytime high temperature and the average nighttime low temperature
Factors that influence a region’s climate
- Diurnal shifts
- How many hours of sunshine the region gets
- Weather threats
How the diurnal shift affects the grapes
- If the diurnal range is small, the grapes will ripen more quickly
- If the diurnal range is large, the grapes will ripen more slowly
Ripening speed determines
How balances the accumulated sugar and acidity is within the grapes
Range of minimum sunshine hours a vine needs during the growing season
1200-1500 minimum, depending on the climate/region
(1300 average)
Weather threats that affect vineyards
- Hail
- Frost
- Deep winter freezes
- Strong wind
How hail affects the vine
- perforating the leaves, making them unable to photosynthesize
- puncturing or destroying berries, making them useless or decreasing that year’s yield
- damaging the vine with small wounds, into which disease and rot can fester
How frost affects the vine
- it can delay budding and flowering (means grapes are at risk of not fully ripening)
- new plant material can freeze and die
- spring frost can decrease the annual yield
When frost is most dangerous
At budburst – March/April in North. Hemisphere, Sept/Oct in South. Hemisphere
Deep freeze affect on vines
If it’s severe, the vines are at risk of being killed
How strong winds affect vineyards
- uproot vines
- blow them over
- blow off delicate flowers, which means no grapes will form
