1. 9/10/2012
Introduction to Vines and
Wines
Hort/VE 113 Fall 2012
Session 5 -Grape Growing:
climate and environment
Climate terminology
• Climate: the average course or condition of
the weather at a place usually over a period of
years as exhibited by temperature, wind
velocity, and precipitation.
• Mesoclimate: the climate of a vineyard site;
up to a region; influenced by prevailing winds,
proximity to water.
• Microclimate: the climate of the grapevine
canopy.
Meso Climates
• Meso
– sites within a region
– air drainage, soil, water table, slope,
aspect,
aspect orientation
– Small end: an extensive vineyard
– Large end: a region– Note: there are many
Meso climates possible in a given region
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2. 9/10/2012
Micro climates
• Micro
– From the scale of inches to the scale of a
few hundred yards
– From the scale of a leaf to the scale of a
vineyard.
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3. 9/10/2012
Important climatic characteristics
• Sunshine
• Heat accumulation (growing degree days)
• Length of growing season (number of
y
frost-free days)
• Cold dormant “chilling” period
• Absolute minimum temperature
• Humidity
• Rainfall during growing season
American Viticultural Areas
“AVA’s”
• Concept of AVA’s—
– Federally recognized growing regions –
American Viticultural Areas
– Designed to give you a geographic and
climatological pedigree for the wine coming
from that AVA
– Also called “Appellations”
The AVAs of WA
• Puget Sound • Columbia Gorge
• Red Mountain • Wahluke Slope
• Walla Walla Valley • Snipes Mountain
• Yakima Valley • Lake Chelan
• Horse Heaven Hills • Columbia Valley
• Rattlesnake Hills • Pending: Naches
Heights; Ancient
Lakes
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4. 9/10/2012
AVA’s were established to help people
try to guess the properties of wines
without tasting them.
• e.g., If you bought a nice Pinot Noir
from one vineyard in the Puget Sound,
you might be able to assume some of
h b bl f
the characteristics of another Pinot
from another winery in the same AVA.
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5. 9/10/2012
Sunlight
• Desirable regardless of which varieties
are grown or the end use
• Required for photosynthesis (production
of carbohydrates)
f y )
• Heats fruit and accelerates ripening
• Stimulates development of fruitful buds
• Helps dry foliage and fruit – reduces
disease
Heat Accumulation
• Growing degree days (GDDs): used to predict
development of crop and determine where grapes will
grow
• GDDs (base 50˚F) = average daily temperature – 50 for
a given 24 hour period:
• Average the min and max temps and subtract 50
degrees
• High of 60 low of 50:
• 60+50 divided by 2 = 55
• 55-50 = 5 GDD
• Counted from April 1 to October 31st.
www.weather.wsu.edu
Average air temp (F) 2 Sept 2008
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6. 9/10/2012
Prosser, WA GDDs Base 50
GDD Calculation
Wine grapes need high GDDs to
accumulate sugar in fruit
• >2500(F˚) preferred for red varieties:
–C b
Cabernet Sauvignon, M l t M lb
tS i Merlot, Malbec
• >1900 preferred for white varieties
– Pinot Noir, Pinot Gris, Riesling,
Gewurztraminer, Muscat, Chardonnay
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7. 9/10/2012
Classification by Maturity
Growing degree days (GDD, 1 April - 31 October, base
temperature 10°C) required to reach acceptable maturity
GDD
Group Red varieties White varieties
(C.)
1 1050 Madeleine Angevine
Chasselas, Muller-
2 1100 Blue Portuguese
Thurgau, Pinot gris
Gewurztraminer,
3 1150 Pinot noir, M
Pi i Meunier, G
i Gamay Sylvarer, Ch d
S l Chardonnay,
Sauvignon blanc
Semillon, Muscadelle,
4 1200 Malbec, Zinfandel, Pinotage
Riesling
Merlot, Cabernet franc, Syrah,
5 1250 Chenin blanc
Cinsaut, Barbera, Sangiovese
6 1300 Cabernet Sauvignon Colombard, Palomino
Muscat of Alexandria,
7 1350 Aramon, Carignan, Grenache
Ugni blanc
8 1400 Tarrango, Terret noir Clairette, Grenache blanc
Length of growing season
• Number of continuous days without
frost
• Frost can freeze buds in the spring,
eliminating crop
• Frost can cause leaves to drop early,
limiting carbohydrate reserves that are
stored over winter
Chilling period
• Required for buds to “break” in spring
– Accumulated degrees below a certain
threshold
• Not usually an issue in the temperate
climates
• Makes tropical viticulture difficult
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8. 9/10/2012
Absolute minimum temperature
• Cold temperatures can
kill buds, canes,
trunks, even entire
vines!
• High variation in cold
hardiness among
h di
species and cultivars
• Makes temperature
moderation by water
(oceans, large lakes)
important
• -10˚F damages most V.
vinifera varieties
Continentality = effects of bodies of
water, slope, elevation on wind
generation
The wind can act to protect grapes
from freezing, overheating and can
remove excess moisture
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9. 9/10/2012
Humidity and rainfall
• Encourage fungal diseases such as
powdery mildew and downy mildew
• Rainfall sometimes provides more
water than desirable
• Dry climate with irrigation reduces
disease and allows the grower to
stress the vine at the appropriate
time
Soils
• Well drained generally best
– Mixtures of sand, gravel, organic matter
• Drainage can be improved with drainage
tile
• Many wines benefit from the mineral
content of the soil– sometimes chalky
• Rootstocks are selected for soil
characteristics (texture, pH)
Soil types
Alluvial - A combination of clay, silt, sand and gravel that forms over
time from mineral deposits left by running water.
Granite - A hard and granular rock with a high content of crystals,
particularly quartz.
Jory - A volcanic soil composed mostly of basalt, which is in turn a hard
and dense soil that often has a glassy appearance.
Limestone or Chalk - A soft soil made primarily from fossilized
seashells.
seashells
Loam - A crumbly mixture of clay, sand and silt.
Marl - A crumbly mixture of different clays as well as calcium and
magnesium carbonates with fossilized shells mixed in as well.
Sandstone - A combination of silica and sand compacted together by
pressure and time.
Tufa - A mix of silica, calcium carbonate and sometimes volcanic ash
that has been deposited over time by streams, lakes and other water
sources.
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10. 9/10/2012
“Terroir”
A French term (much discussed) for the
total natural environment of any
viticultural site
Major components have been described:
Soil
Macro-,meso-, and microclimates
“Terroir”
Determinants of terroir include:
• Climate-temperature and rainfall
• Sunlight energy-received per unit of
g gy p
land area
• Topography-altitude, slope, and aspect
• Geology – more on this later
• Hydrology –soil water relations
Fine wines
• All involve matching the grape variety
to the local “terroir”
• Viticulturists have learned how to
manage the vines to achieve the best
results for that particular location
• Certain climate years yield
outstanding “vintages”
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11. 9/10/2012
Introduction to Vines and
Wines
Hort/VE 113 Fall 2012
Sessions 6 & 7-Grape Growing
pruning and training
Lesson Objectives:
Learn the importance of
pruning in vine and crop management
Understand how pruning affects
crop l d and vegetative growth
load d t ti th
Understand how pruning levels
affect fruit quality
Concepts of Pruning
What is pruning? What is the difference
between pruning and training?
Pruning is the removal of unwanted wood
or parts of the vine…and
f h i d
Training is the establishment of the
permanent vine structure or form.
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12. 9/10/2012
Why prune?
1. Establish and maintain vine structure
and cropping
2.
2 Distribute crop load
3. Control and adjust crop load
4. Maintain or control vegetative growth
The principal objective of
pruning is to maintain a
balance between fruiting (crop
load) and vegetative growth
(canopy)
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