Winter Canola: Setting the Stage for Successful Establishment

Winter-hardy canola varieties make production possible across much of Kansas. When planted at the right time into good soil moisture, canola has the best chance of establishing strong fall growth and surviving the winter.

This article covers three key areas for getting a successful start: variety selection, site selection, and seedbed preparation. A companion eUpdate article addresses other management considerations such as seeding date, rate, row spacing, fertility, and pest management.

Choose the Best Variety

Choose varieties based on winter survival, yield, oil content, herbicide tolerance, disease resistance, maturity, lodging susceptibility, and shatter tolerance. Winter hardiness should be the top priority in new production areas.

Producers have the option of selecting either open-pollinated varieties or hybrids.

Open-pollinated varieties: Common in the southern Great Plains; reliable overwintering and strong yield potential. Roundup Ready options are available for broad-spectrum weed control.

Hybrids: Larger seed size for easier seed metering, vigorous growth, and high yield and oil potential. Clearfield herbicide tolerance is available in some hybrids.

Varieties tolerant to sulfonylurea (SU) herbicide carryover can be used after crops treated with products like chlorsulfuron, metsulfuron methyl, avoiding the long plant-back intervals. Some Roundup Ready varieties also have SU carryover tolerance.

Planting two or more varieties with different maturities can spread harvest timing and help reduce risk. Consider pairing a proven variety with a new one to evaluate performance.

For yield data and winter survival scores, producers may consult National Winter Canola Variety Trial publications that are available at the K-State Extension Bookstore.

Site Selection

Canola grows on a range of soils but performs best on well-drained, medium-textured soils with a pH between 5.5 and 7.0. Correct low pH with lime before planting. Avoid poorly drained or waterlogged sites. Liming should be considered when the soil pH is less than 5.5.

Be mindful when planting canola after crops such as sunflower, soybean, alfalfa, or cotton. These crops share similar diseases with canola. Continuous canola is not recommended, and it is not insurable. Rotate with grass crops (wheat, corn, or sorghum) to minimize disease risk.

Canola will perform best when adequate time is given after the preceding crop to allow for soil moisture recharge and weed control, and where there is adequate time to get the canola planted early enough to help the plants survive over winter.

Avoid fields with heavy pressure from winter annual broadleaf weeds if possible. If planting in these conditions, consider a Roundup Ready variety. Grassy winter annual weeds are easily controlled by using clethodim, quizalofop, or sethoxydim in conventional canola or by using the Roundup Ready or Clearfield canola systems. Be aware of herbicide history - winter canola is sensitive to Group 2 and triazine herbicide carryover, which may require 18 months or more before planting.

Seedbed Preparation

Because of its small seed size, a properly prepared seedbed is critical for successful canola establishment. Open-pollinated varieties typically range from 100,000 to 125,000 seeds per pound, and hybrids range from 70,000 to 100,000 seeds per pound.

A level, firm seedbed with adequate moisture within the top inch is preferred. Because canola seed is placed shallow, in the soil layer that dries fastest, the top inch needs to stay damp for several days after sowing. A seedbed with many large clumps results in poor seed placement and seed-to-soil contact. An overworked seedbed may be depleted of moisture and will crust easily, potentially inhibiting emergence. In addition, this could promote deep placement of the seed.

If using tillage, perform the most aggressive tillage as early as possible, with each succeeding tillage operation being shallower than the last. Incorporate fertilizer and herbicide with the last tillage operation. Some producers perform one aggressive tillage operation as early as possible and then control newly emerged weeds chemically. Planting into this “stale” seedbed will help ensure adequate moisture for establishment (Figure 1).

winter canola staled seedbed

Figure 1. Winter canola seeded into a stale seedbed at the North Central Kansas Experiment Field near Belleville. Photo by Mike Stamm, K-State Dept. of Agronomy.

No-Till Planting Considerations

No-till planting is an option, and some long-term no-till producers have grown canola successfully using this practice (Figure 2). With proper settings, no-till planting can result in very good stands. However, maintaining stands over the winter can be difficult with low soil disturbance in heavy residue cover. This challenge has been overcome by burning surface residue immediately before planting, removing the residue (i.e., baling), vertical tillage, or using a more aggressive residue manager that removes residue from the seed row.

canola rows with residue between

Figure 2. Overwintering canola established under no-tillage in 30-inch rows in southwest Kansas. Photo by Mike Stamm, K-State Dept. of Agronomy.

Ensure that drills and planters are properly set and consider using a setup that creates a more disturbed seed row. Using a high-disturbance opener (such as a coulter, residue manager, or hoe-type opener) in no-till can improve winter survival and result in yields comparable to those obtained in tilled fields.

Weeds must be controlled chemically, mechanically, or with a combination of both methods prior to planting because canola seedlings are not competitive with established weeds.

Additional Resources

 

Mike Stamm, Canola Breeder
mjstamm@ksu.edu

John Holman, Cropping Systems Agronomist – Garden City
jholman@ksu.edu

Pramod Pokhrel, Cropping Systems Agronomist – Colby
ppokhrel@ksu.edu