By Sara Tetland, PAg, Provincial Specialist Cereal Crops, Regina
While growing winter wheat requires extra planning since seeding often overlaps with the busy harvest season, there are benefits to growing it. This includes expanding the crop rotation, providing ground coverage to reduce erosion, and spreading out the timing of harvest operations. Winter wheat also tends to avoid or escape pest issues like Fusarium head blight and wheat midge.
Below are some agronomic considerations and tips for growing winter wheat:
- Field Selection - To protect the crop from harsh Saskatchewan winters, it is important to direct seed winter wheat into standing stubble. Having tall, intact stubble helps trap snow and provide snow cover to insulate the overwintering crop. Canola or mustard stubble is preferred because it usually provides enough stubble to trap snow and has stiff stems which will help the stubble stay upright throughout the winter. Canola also provides a low disease, insect and pest risk. Cereals like barley or oats may be used, but it is best to avoid wheat stubble to avoid disease issues. Pulses like lentils, field peas and dry beans are not ideal because of their poor snow-trapping ability.
- Seeding Date - The optimum seeding date ranges from late-August to mid-September, depending what area you are in. These dates are based on seeding dates that provide optimal growth for the highest winter hardiness. Before freeze up, plants should have a well developed crown with three to four leaves and one tiller. Seeding too early results in excessive fall growth and reduces winter hardiness, while seeding too late results in poorly established plants with low winter survival potential. The Saskatchewan Crop Insurance deadline for winterkill coverage for winter wheat is September 30th.
The optimum seeding dates into no-till, standing stubble is:
- August 27: Meadow Lake/Prince Albert/Nipawin areas
- August 30: North Battleford/Saskatoon/Wynyard/Yorkton areas
- September 3: Kindersley/Swift Current areas
- September 6: Maple Creek/Estevan areas
- Seeding Rate - Seeding rate should be calculated using the thousand-kernel weight and seeding survival rate. Higher seeding rates will increase the plant stand and uniformity of the crop. The desired plant population is similar to spring wheat, but the seeding rate has to increase to account for addition winter kill loss in winter wheat. The ideal target plant population for winter wheat is 25 to 30 plants per square foot.
- Seeding Depth - Shallow seeding helps ensure that the plants germinate without using too much energy, but it must be deep enough to ensure the seed is in good contact with the soil. A seeding depth of 0.5 to one inch is recommended.
- Fertility - All the crop nitrogen can be applied at the time of seeding, but there is risk of loss to the environment. An alternative is to apply some of the fertilizer at seeding and top-dress the rest early in the spring. Since winter wheat grows early in the spring and requires good fertility early on to maintain its yield, applying earlier is better.
Winter wheat also yields higher than spring wheat, so it is important to adjust the fertility needs for those higher yields. Assessing the fields fertility needs can be done by using soil test recommendations using a reasonable yield target. - Weed Control - For winter wheat, winter annuals and perennial weeds pose the greatest challenge. A pre-seeding burn off, including pre-harvest weed control in the current years crop, can help control these weeds. Control of winter annuals in the spring – once the weeds have emerged – is another option.
Control of volunteers are important, especially when seeding into wheat stubble. A seven-to-10 day break without vegetative growth is required to break the “green bridge” that allows wheat streak mosaic virus to persist and effect the winter wheat crop. A pre-seeding herbicide application can help break this green bridge.
For more information visit the winter wheat factsheetor visit the Western Winter Wheat Initiative’s webpage.