Barossa Valley, SA, Australia / Riesling Grape

Total GDD: 2608 (Feb 11)

Day 195 / 288 (68%)

Current Season

Total GDD: 2608 (Feb 11)

Method: 50°F Sine

7-Day Daily Avg: 27.8

7-Day Projection: 2802 by Feb 18

Season: Aug 01, 25 - May 15, 2026

Key Freeze Dates (32°F)

Last Freeze:
10%: 08-02
50%: 08-28
90%: 09-28

First Freeze:
10%: 04-25
50%: 05-21
90%: 06-18

Growing Degree Days (GDD) track heat accumulation to predict when plants reach growth stages, pests emerge, and diseases become active.

Thresholds mark specific GDD values when events typically occur, with crossing dates showing when your season reaches each milestone.

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Thresholds & Notes

Budbreak (E-L 4) 150 °D

Sep 9, 2025 | Aug 26, 2024 | Sep 5, 2023 | Sep 18, 2022

Growth Stage

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Frost protection critical through Sept 21. Eutypa dieback pruning.

10 cm Shoots (E-L 12) 350 °D

Oct 9, 2025 | Sep 26, 2024 | Sep 29, 2023 | Oct 19, 2022

Growth Stage

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First powdery mildew spray. Shoot thinning begins.

Inflorescences Clear (E-L 17) 600 °D

Oct 31, 2025 | Oct 17, 2024 | Oct 23, 2023 | Nov 12, 2022

Growth Stage

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Critical spray timing for disease.

Flowering (E-L 23) 850 °D

Nov 24, 2025 | Nov 6, 2024 | Nov 12, 2023 | Dec 5, 2022

Growth Stage

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No sprays during bloom. Monitor for poor fruit set.

Fruit Set (E-L 27) 1100 °D

Dec 11, 2025 | Nov 22, 2024 | Dec 1, 2023 | Dec 23, 2022

Growth Stage

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Bunch thinning decisions. Irrigation scheduling critical.

Bunch Closure (E-L 33) 1500 °D

Jan 1, 2026 | Dec 11, 2024 | Dec 23, 2023 | Jan 11, 2023

Growth Stage

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Final botrytis spray. Bird netting for early varieties.

Veraison (E-L 35) 1900 °D

Jan 18, 2026 | Jan 12, 2024 | Dec 31, 2024 | Jan 28, 2023

Growth Stage

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Color change begins. Reduce irrigation. Begin maturity sampling.

Berries Ripe - Riesling (E-L 38) 2400 °D

Feb 4, 2026 | Jan 20, 2025 | Feb 3, 2024 | Feb 22, 2023

Growth Stage

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11-12° Baumé. Acid retention critical in hot years.

Berries Ripe - Shiraz (E-L 38) 2900 °D

Feb 10, 2025 | Feb 24, 2024 | Mar 23, 2023

Growth Stage

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13.5-14.5° Baumé. Multiple picks for premium parcels.

Berries Ripe - Cabernet (E-L 38) 3300 °D

Feb 28, 2025 | Mar 11, 2024 | May 2, 2023

Growth Stage

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13-14° Baumé. Tannin ripeness critical. Frost risk returning.