Chapter 5 - The Growing Environment Flashcards
Name the 5 things a vine needs
Heat, sunlight, water, nutrients and carbon dioxide
Describe the vine’s growth cycle
In winter: dormant, no green parts
Begin spring: budburst, new shoots grow
Late spring: flowers and grapes form (fruitset)
Summer: grapes grow (still hard, acidic, green, no sugar
Late summer, early autumn: grapes ripen
Autumn: harvest, end of growing season
Late autumn: leaves fall
What is veraison and when does it occur?
Grapes change colour and start to ripen. Early autumn.
What is photosynthesis
The process through which the plant converts carbon dioxide and water into glucose with the help of sunlight
What is the temperature limit for a vine to grow?
10 C, below that it lies dormant (winter)
Which part of the cycle is heat very important?
Growing season. The plant needs lots of heat for flowering, fruitset and ripening
Do all vines have the same need for heat?
No, some varieties can thrive under lower temperatures than others.
Riesling grows very in cool regions, where Grenache needs a lot of heat.
Name 6 factors affecting heat for vines
Latitude Altitude Ocean currents Fog Soil Aspect
What is the best Latitude for vine growing?
Between 30 and 50 degrees (north and south of the equator)
Name 2 cooling ocean currants, and the areas they affect
The Humbolt Current (Chile) Benguela Current (South Africa)
Name a warming ocean currant and the area it affects
The Gulf stream for NW-Europe
Name 2 area’s where fog plays an important role
California and Cassablanca Valley in Chile
What is aspect and how does is affect heat
The direction a slope faces. Vineyards that face the equator get more sunlight and thus more heat.
Where is aspect especially important?
In cool climates where every bit of heat is needed for ripening.
What factor enhances the effect of the correct aspect?
How steep a slope is. The steeper the better.
What is continentality?
The temperature difference between the hottest months and the coldest months
How do large bodies of water influence continentality?
Since water heats up and cools down more slowly than land, they can have a heating/cooling effect on the surrounding air and thus landmass.
So continentality is lower near large bodies of water
What is the effect of continentality?
It determines the length of the growing season, and with that the total amount of heat available to a vine
What is the diurnal range?
The temperature difference between day and night
What is the impact of diurnal range?
Cool nights help preserve acidity and aroma. Warm nights accelerate ripening
Name 2 influences on diurnal range
Bodies of water can hold warmth during the night and provide cooling breezes during the day
Cloud cover can hold onto warmth during the night and cover from sun during the day
At which temperature can a vine be damages or even kiled?
-20c
What is earthing up?
The process of protecting the graft from frost by burrying it with earth. The graft is the most sensitive part of the vine
What sre the risks of a mild winter?
The plant will not go dorment, resulting in an extra crop. This decreases the lifespan of the vine and the quality of the grapes will suffer.
Mild winters also mean larger populations of insects and pests.
What is the danger of a spring frost?
In spring, there are new buds and shoots, which are vulnerable to frost.
Name 4 forms of protection against spring frost
Heaters - create air movement in te vineyard, preventing cold air from settling and causing frost
Wind machines
Sprinklers - as the water freezes, it releases warmth into the plant, protecting it
Vineyard design - avoid low lying areas, plant on slopes (preferably in the middle), train vines high above the ground to avoid the coldest air
What is a consequence of low temperatures in spring?
Delay in budburst, resulting in a shorter growing season and sometimes not enough time for ripening before it gets too cold again.
Flowering and fruitset can also be disrupted, resluting in a smaller crop
What is the risk of prolonged periods of extreme heat?
The vine activity will slow or even stop. Which disrupts the ripening process
Name 3 factors that affect sunlight
Latitude - the further from the equator, the longer the day during growing season. (Important for riesling in Germany)
Seas and Lakes - means more cloud cover, and thus less sunlight. Proximity to rivers can be beneficial because of sunlight reflecting
Aspect - steeper slopes benefit even more from this
During which processes is sunlight especially important?
Flowering and fruitset. Cloud cover can can result in smaller crops.
Ripening. Sunlight is needed for FS, so a lack of it during this period can stop the grapes from ripening fully.
What is a danger of too much (intense) sunlight?
Grapes can get sunburnt. Resulting in bitter flavours
What does a vine need water for?
Fotosynthesis and swelling the grapes
How does a vine collect water?
Through transpiration. Water is drawn from the soils through the plant to the leaves
The amount of water a plant needs is determinde by what?
Temperature. The warmer it is, the more water evaporates through the leaves
How can withholding water be good for the crop?
When the vine has enough leaves, limiting the water intake will shift the vine’s focus from creating new shoots to grape ripening.
Extra: it also reduces the impact of shading, because the canopy will not grow
What are the three main irrigation techniques?
Drip irrigation - computer controlled, expensive, each vine has its own dripper
Sprinklers - lots of water wasteage and increases the risk of disease due to the damp conditions it creates
Flood irrigation
What is the risk of drought?
The vine will temporarily stop transpiration. If the drought lasts, fotosynthesis stops, leaves fall and grapes stop ripening. (This is called: water stress)
What happens when a plant gets too much water during the growing season?
It will continue to grow leaves and shoot during the ripening season. Leaving less energy (glucose) for the grapes.
It will also increase conopy cover, restricting sunlight exposure
What is waterlogging?
When the ground is saturated with water. Causing the roots to die.
How can waterlogging be avoided?
By planting on slopes or installing drainage
Name three risks of heavy rainfall
Flowering and fruitset can be disrupted, resulting in a smaller crop
Damp conditions encourage fungal diseases
Heavy rain before harvest causes the grapes to swell up. Diluting flavours or even breaking the skin (causing disease)
Name an area especially prone to hail
Mendoza, Argentina
What is climate
The annual pattern of temperature, sunlight and rainfall. Avaraged out over several years
What is weather?
The annual variation that happens relative to the climactic average
Name the 4 temperature types for climates
Cool climate: growing seasons avg <16,5
Moderate climate: growing seasons between 16,5 and 18,5
Warm climate: between 18,5 and 21
Hot climate: >21
Name the 3 climate categories
Continental
Maritime
Mediterranean
What is a continental climate?
A climate with high continentality
Short, dry summers
The cool ones (Chablis, Champagne) are at risk from spring frost and low temperatures during growing season. This requires early ripening grapes
Explain the mediterranean climate
Cool to moderate
Low continentality
Evely spread out rainfall moderates temperature. But can also be a risk to fruitset and harvest.
Grapes can ripen untill well into autumn
Why is Maritime Bordeaux well suited for Cab Sauv?
Because of the moderating rainfall throughout the year, grapes can ripen for a long time. Which is well suited for this thick skinned grape.
Explain mediterranean climates
Low continentality
Warm and dry summers
Drought can be a risk
More sunlight and warmth result in fuller bodies, riper tannins, higher alcohol and lower acidity
Where are mediterranean climates found?
Coastal California, Chile, South Africa and SE Australia
What do stones on the surface of the vineyard do?
They heat up the vineyard (during the night)
What is humus?
Organic matter in the soil of the vineyard. Made up of decomposing plant and animal material
How is water stored in the soil?
By binding to clay or humus
What is a risk of too much clay in the soil?
Waterlogging
What is a risk of too much sand and stones in the soil?
They do not bind well with water and promote drainage. Insufficient water may be retained
What are the most important nitrients for the vine? (3)
Nitrogen, phosphorus ans potassium
What is a risk of too many nutrients in the soil?
Too much growth, a large canopy, leading to too much shading
What is chlorosis?
A result of a lack of nutrients in the soil. Leading to yellow leaves and disrupted photosynthesis
