WSET D1 Vine Growth Cycle Flashcards
Name in Order the Steps to the Vine Growth Cycle and Timing
Dormancy: November - March Budburst: February - April Shoot & Leaf Growth: February - July Flowering & Fruitset: May - June Grape Development: June - October Harvest: September - October Leaf Fall and Dormancy: November - March *This is Northern Hemisphere, Southern is +6 months
Describe Dormancy and When in Occurs, Temperature the Vine Needs
How the Vine Substains itself
Adverse Constions
N. Hem- Nov-Mar S. Hem - May- Sept
When average air temperature is below 10C (50F) and too cold for the vine to grow
Because of no leaves, no photosythesis, so the vine substains itself by using stored carbohydrates, mainly starch accumulated in previous growing season in roots, trunk and branches
Adverse conditions are either Extremely too cold or Unusually mild temperatures
Too cold -20C (-4F) will hurt or kill vine, -25C (-13F) will kill most vitis vinifera
Describe Budburst (Budbreak) and When in Occurs, Temperature
The Four Factors that influence the Timing of Budburst and explain pros and cons of them
Adverse Conditions
N Hem- March- April S. Hem- Sept-October
Marks end of Dormancy, Buds (compound from previous growing season) swell and open, green shoots start to emerge. Above 10C (50F)
Four Factors
1. Air Temperature - Above 10C (50F),
Places with rapidly increasing Spring Temp can be advantageous leading to even ripeness later (Continental)
Places with Less Contrast between Winter and Spring, Less syrcronized can lead to lower yields. (Maritime)
- Soil Temp - Higher soil temp encourages earleir Budbreak. Free draining soils (sand) can help warm faster that water storing soils (clay)
- Grape Variety - Early Budding Vs Later Budding
Early Ex. (Cooler Temp) - Chard, PN, Merlot, Grenache
Late Ex. (Higher Temps, less risk of Frost) - Sauv Blanc, Cab Sauv, Syrah - Human Factors - Growing practices, Late pruning can postpone Buburst, used where Spring frost is an issue
Adverse Conditions
Frost
Cold Soils
Describe Shoot & Leaf Growth, When in Occurs
Vigour - Factors it depends on
What Nutrients Vines Need as they Grow
Adverse Conditions
N. Hem - March-July S. Hem - Sept - Jan
Shoots continue to grow, leaves and inflorescences mature. Fastest rate of growth generally occurs betweek budburst and flowering.
Vigour describes vegetative vine growth, shoots leaves aand lateral shoots, implications on yield and ripening grapes. It depends on Natural Resources (Temperature, Water, Nutrients) and Planting Material (Grape Variety, Clone, Rootstock)
Carbs initial shoot growth, then Principally Nitrogen, Potassium, and Phosphorus
Adverse- Low Carb Levels (Removing too many leaves, caused by precious growing season)
Water Stress (Dont want to limit photosynthesis right now)
Describe Flowering and Fruitset, When in Occurs, and What the Vine Needs
Conditions for Successfull Flowering
Conditions for Successful Fruitset
Adverse Condtions to Flowering and Fruitset
N. Hem - May - June S. Hem - Nov - Dec
Flowering - the opening of the individual flowers within an Inflorescence, polination occurs
Fruitset - describes the transition from flower into grape
Vine Needs:
- Warm Temp - Min 17C (63F)
- Sunlight, Warmth, Water, and Nutrients for bud fruitfullness in next growing season
Conditions for Sucessfull Flowering
-Very temperature dependent, warm conditions lead to earlier flowering - atleast 17C (63F), Inflorescence can finish flowering in a few days in warm weather, take weeks in colder weather
Conditions for Successful Fruitset
-Pollen germitation requires warm temperatures 26-32C (79-90F), 30% of flowers become grapes (0-60%)
Adverse Conditions
-Rainy, Cloudy, Windy, Cold Temps can cause irregular fruitset
Name 2 Common forms of irregular fruit set, what they are and when they occur
Coulure - A condition of the grape bunch in which fruit set has failed for a high proportion of the flowers
Can reduce yield, caused by imbalance of carbohydrate levels or vigourous shoot growth in very fertile soils. Cab, Merlot, Grenache, Malbec are very susceptible.
Millerandage- condition where a high proportion of grapes are seedless. Smaller than grapes with seeds, may reduce volume of prudction, stay green and underipe. Results from cold wet windy weather.
Susceptible Varieties - Chardonnay Merlot
Name Parts of the Vine Flower and how it works
(POSESOP AF) Stamen - Anther & Filament Pollen Stigma Pollen Tube Ovule Ovary Egg
What time of year does Grape Development occur
What are the 4 stages
What does the vine need
Adverse Conditions
N. Hem - June - Oct S. Hem - Dec-April
- Early Grape Growth - Green grapes grow in size, Malic and Tartaric acids accumulate, some aroma compounds and aroma precursors develop, Methoxypyrazine -herbaceos aromas/flavors ex. Sauv Blanc, bitter tannins)
- Verasion - Lag phase (grape growth slows), cell walls stretchy and supple, green chlorophyll broken down in black grapes to become red, Anthocyanins
3.Ripening- Sugar and Water accumulate, acid falls.
Tannins, Color and other aroma precusors develop. Photosynthesis maximizes at 18-33C (64-91F) Extreme Water stress can stop photosythesis. Too warm, sugar out perform tannins. Tartaric & Malic Diluted. Tannin decrease. Terpenes (floral and citrus found in Muscat)
4.Extra Ripening
Vine Needs
Sunlight, Warmth, Mild Water Stress
Adverse Conditions
- Too much water and nutrients (nitrogen)
- Excessive Shading of Grapes
- Very Cold and Very hot conditions throughout the day and night
Acid Loss and Retention during ripening- Page 20
Pg 22 defining ripeness
Read 2nd Paragraph
What Factors do length of ripening depend on
- Grape Variety - some ripen earlier than others
Ex. Early - Chard, PN
Ex. Late - Cab Sauv, Granache - Climactic Conditions - Sugar ripening quickest in warm dry conditions, too hot can shut down vine
- Vine & Vineyard Management - High Yields, Excessive Shading, Shoots avctively growing, all can slow down ripening
- Time of Harvest - Human factors (wine style, logistics) and Natural Factors (weather, onset of disease)
