Crop & Pest Report


| Share

Canola Early Season Growth Stages (05/11/17)

Understanding the growth and development of a canola plant helps the producer make more effective management decisions.

Canola Early Season Growth Stages

Understanding the growth and development of a canola plant helps the producer make more effective management decisions. Early season canola growth is characterized by the germination process and two main vegetative growth stages. The length of each growth stage is influenced by temperature, moisture, light, nutrients and hybrid. Growth stages of canola can be estimated based on accumulative canola growing degree days, with a base temperature of 41oF. The model predicts that the seedling will be established at about 256 accumulated canola GDD’s. The canola growth stage can be estimated using the North Dakota Agricultural Weather Network at Selecting a specific nearby weather station and entering the canola planting date will provide a local estimate of the canola growth stage.

Pre-emergence (Germination)

The germination process involves water absorption, swelling, splitting of the seed coat and emergence of the root tip. Cotyledons are pushed through the soil surface by an active hypocotyl. Germination typically takes from four to 10 days, depending on soil temperature and moisture, seed soil contact and planting depth. During this stage, canola is susceptible to many soil-borne pathogens.


Once emerged, the cotyledons open and supply the new seedling with nourishment. At this stage, the seedling still is vulnerable to soil-borne pathogens and very susceptible to flea beetle injury. The growing point of canola is between the two cotyledons. The exposed growing point is susceptible to spring frosts, wind-blown soil particles, insects and hail damage. Canola is a very poor competitor with weeds, and good stand establishment is very important.


The first true leaves develop four to eight days after emergence. The plant quickly establishes a rosette with older leaves at the base increasing in size and smaller, younger leaves developing in the center. During this time, the stem length remains basically unchanged although its thickness increases. The rosette stage is characterized by an increase in leaf area index. Rapid and abundant leaf growth captures more sunlight and produces more food for the plant, thus producing more dry matter per day and increasing yield potential. A rapidly developing canola canopy encourages root growth, reduces soil moisture evaporation and shades weeds.

 Hans Kandel

Extension Agronomist Broadleaf Crops

This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

USDA logo

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.