L3C05 The Growing Environment Flashcards
What is the one factor influencing a plant’s growth that does not vary?
CO2
How is a region’s climate defined?
The annual pattern of temperature, sunlight and rainfall averaged out over several years
How is weather defined?
The annual variation that happens relative to the climatic average
Below what temperature is it too cold for a vine’s cells to function?
10 degrees C
What happens to a vine above 22 degrees?
The vine’s cell start to consume more sugar than the vine can produce
In order to ripen grapes successfully, the vine needs the average temperature to be between…
16 and 21 degrees C
What determines which vines will thrive within a certain region?
Temperature
What has an impact on each stage of a vine’s cycle?
Temperature
What occurs later in a cooler region?
Bud burst
…and…can be disrupted in a cooler temperature, doing what to yields?
Flowering and fruitset.
Reducing yields.
If temperature is cool during ripening, what happens to acidity and sugar levels?
Acid falls less and less sugar is accumulated
What may happen to black grapes in cool growing conditions?
They will produce wines which are overly astringent and herbaceous (a result of being physiologically unripe)
Why can white grapes cope with cooler conditions better?
They have no need for ripe tannins and wines are balanced with higher acidity levels
List in order the key stages of a vine’s growth cycle…
Budburst
Early shoot and leaf growth
Flowering and fruit set
Véraison/berry ripening
Harvest
Winter dormancy
List the factors affecting annual temperature…
Latitude
Altitude
Ocean currents
Fog
Soil
Aspect
How does latitude affect a vine’s temperature needs?
The further from the equator, the cooler an area is on average.
What approximate latitudes are best for viticulture? Why?
30 - 50 degrees. These latitudes satisfy a vine’s need for warmth, but also winter dormancy.
How does temperature drop with altitude?
0.6 degrees C with every 100m increase in altitude
How do ocean currents affect climate/weather?
By cooling or warming the air above and around them
How does fog affect temperature? List two examples of areas where this is an important factor…
It cools an area.
California and Casablanca in Chile.
What kind of soil absorbs and reradiates the sun’s heat?
Darker soils or those with a higher stone and rock content
How does soil with a high water content affect ripening?
It delays it, as it takes more energy to heat the soil and heat from the vines is conducted away more quickly
How does aspect affect ripening? Give an example of a region which benefits particularly from a good aspect…
The side of a slope facing towards the equator receives more sunlight and heat.
The Mosel Valley.
How is continentality defined?
It is the temperature difference between winter and summer
What is the main factor affecting continentality? Why?
Proximity of large bodies of water.
They cool down and heat up slower than land masses.
Name the four main inputs required for a vine
Heat
Sunlight
Water
Nutrients
What gives a vine heat?
Sunlight and soil
Where does a vine get light from?
The sun and the soil
How does a vine get water?
Rainfall, irrigation and water stored in soil/bedrock
Where does a vine get its nutrients?
Soil deposits
Bedrock
Humus
Fertiliser
What’s the biggest factor that can influence diurnal range?
Seas and lakes
What can affect levels of cloud cover?
Smaller bodies of water
What two positive effects do cool nights have on a vineyard?
They help the vines rest, extending the growing season They help slow the loss of volatile aromas
What effect do warm nights have on a vineyard?
They help to accelerate ripening, particularly the production of sugar
What kind of wines do regions with a high diurnal range generally create?
Fresher and more aromatic
What is the impact on wine of a smaller diurnal range?
They are usually fuller bodied
Name a rare region with a low continentality, but high diurnal range. Why?
Napa Valley. It’s close to the Pacific, moderating continentality, but experiences on-shore and off-shore breezes and fogs, increasing diurnal range
What is Winter Freeze?
When the temp drops below -20 deg C. This can damage or kill a vine
The part of a vine most at risk during winter freeze is…
The graft callus
How can graft calluses be protected during winter freeze?
By covering up the callus with soil (sometimes the whole vine)
What is Spring frost?
Cold air below 0 deg C collecting at ground level and freezing any settled water vapour
What happens to a vine during spring frosts?
Newly burst buds or shoots are killed by frost
What are the four main methods of protection against frost?
Burners
Wind machines
Sprinklers
Vineyard design
What are burners/smudge pots?
The heat they generate creates movement in the air, preventing cold air from settling and causing frost. Smudge pots also generate smoke, insulating heat from the vineyard
Why/how do sprinklers work in frost protection?
When their water freezes, it releases latent heat, protecting buds and shoots