May 23, 2013

GDDs to date

After the slow start, growing degree days (GDDs) are accumulating fast with warm weather. See the AAFC maps for GDDs accumulated across the Prairies up to May 13 and up to May 20. Click here to create other AAFC weather maps. GDDs are calculated by averaging daily maximum and daily minimum temperatures for each day, and subtracting the assumed minimum temperature (Base T) required for growth to proceed. Canola GDDs outline in the table below are based on a Base 0°C. A day with a high of 20°C and a low of 10°C would contribute 15 GDDs on a Base 0 scale.

Accumulated GDDs to date (as shown on the AAFC maps) would not count toward canola seeded today. Napus seeded today would need roughly another 1,500 GDDs before frost to reach maturity.

Growing Degree Days (GDDs) Base 0°C required to reach various growth stages for Napus and Rapa canola.
Growing Degree Days (GDDs) Base 0°C required to reach various growth stages for Napus and Rapa canola.

GDDs accumulated to May 20 across the Prairies. The dark green area leads with 368-403.
GDDs accumulated to May 20 across the Prairies. The dark green area leads with 368-403, up almost 100 from last week (see below).

GDDs as of May 13. The dark green area is at 278-308.
GDDs as of May 13. The dark green area is at 278-308.

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