Manitoba, Canada / Canola (Winkler)

Total GDD: 3395 (Sep 30)

Day 153 / 153 (100%)

Current Season

Total GDD: 3395 (Sep 30)

Method: 41°F

7-Day Daily Avg: 20.3

7-Day Projection: 3537 by Oct 07

Season: May 01, 25 - Sep 30, 2025

Key Freeze Dates (28°F)

Last Freeze:
10%: 04-21
50%: 04-30
90%: 05-13

First Freeze:
10%: 09-27
50%: 10-11
90%: 10-25

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.

Visit About and FAQ to learn more

Thresholds & Notes

Emergence 150 °D

May 9, 2025 | May 12, 2024 | May 12, 2023

Growth Stage

Hide notes

Cotyledons visible. Flea beetle scouting critical - threshold 25% leaf area loss.

2-Leaf (Rosette) 300 °D

May 14, 2025 | May 22, 2024 | May 18, 2023

Growth Stage

Hide notes

First true leaves. Frost tolerant to 28°F at this stage.

4-Leaf 475 °D

May 28, 2025 | Jun 3, 2024 | May 27, 2023

Growth Stage

Hide notes

Rosette expanding. Herbicide timing window for broadleaf weeds.

6-Leaf (Late Rosette) 650 °D

Jun 4, 2025 | Jun 12, 2024 | Jun 2, 2023

Growth Stage

Hide notes

Bolting imminent. Final fungicide timing for blackleg if needed.

Bolting 850 °D

Jun 14, 2025 | Jun 22, 2024 | Jun 8, 2023

Growth Stage

Hide notes

Stem elongation begins. Plant commits to reproductive growth.

Bud Formation 1000 °D

Jun 20, 2025 | Jun 28, 2024 | Jun 14, 2023

Growth Stage

Hide notes

Green buds visible, still enclosed. Sclerotinia scouting begins.

First Flower 1200 °D

Jun 29, 2025 | Jul 7, 2024 | Jun 21, 2023

Growth Stage

Hide notes

10% bloom. Sclerotinia fungicide window opens (20-50% bloom). Most frost-sensitive stage.

Full Flower 1450 °D

Jul 7, 2025 | Jul 15, 2024 | Jun 30, 2023

Growth Stage

Hide notes

50%+ bloom. Peak pollinator activity. Heat stress above 86°F reduces pod set.

End of Flower 1850 °D

Jul 24, 2025 | Jul 29, 2024 | Jul 17, 2023

Growth Stage

Hide notes

Petals dropping. Pod fill begins. Lygus bug threshold 10-20/10 sweeps.

Pod Development 2300 °D

Aug 11, 2025 | Aug 16, 2024 | Aug 3, 2023

Growth Stage

Hide notes

Seeds visible in pods. Maintain moisture for seed fill. Green seed risk if frost hits now.

Seed Color Change 2800 °D

Aug 31, 2025 | Sep 5, 2024 | Aug 24, 2023

Growth Stage

Hide notes

Swath timing. Seeds firm, roll but don't crush. Comfortable margin before Sept 27 hard freeze.

Harvest Ready 3000 °D

Sep 13, 2025 | Sep 14, 2024 | Sep 1, 2023

Growth Stage

Hide notes

<10% seed moisture for straight-cut. Red River Valley delivers ~3,485 GDD by Sept 27 (10% freeze).