Ontario Cover Crop Recipe – Wheat Going to Corn: Underseed Red Clover

The following recipe provides an introductory approach to underseeding a red clover cover crop into winter wheat prior to corn. Adding red clover to a wheat-corn-soybean rotation can improve corn and soybean yields, promote better soil, and provide a nitrogen credit, depending on growth and tillage. With good management, these potential benefits make a red clover cover crop worth investing in.

Planning and Preparation

• Planning—Start small with one field. Prioritize cover crop management based on your goals. Avoid fields with a history of poor drainage, water ponding, or fertility issues.
• Wheat variety and planting—No modifications to wheat variety and planting are required for the successful adoption of a red clover cover crop.
• Winter wheat herbicides—Bromoxynil or MCPA are registered for wheat underseeded with red clover but with specific precautions to avoid injury. See Table 7-3, Herbicide Treatment Rates for Cereals, in Guide to Weed Control: Field Crops (see Resources).
• Tillage or no-tillage—Red clover establishment may be more challenging in no-till systems. In fields with high residue, light tillage prior to wheat planting may improve seed-soil contact and establishment of red clover.
• Fertility or liming—No changes are needed if applying P, K, lime, or manure in the fall before wheat planting.
• Seed purchase—Seed prices can vary depending on the time of year; therefore, it is best to order seeds early. Red clover seed is readily available across Ontario. (See Cover Crop Seed Suppliers in Resources.)
• Variety selection—Ontario growers can choose between double-cut or single-cut varieties, or a mix of both. Single-cut types tend to have less top growth than double-cut types. In thin wheat stands, choose single-cut; otherwise the height of double-cut may pose an issue when combining. Single-cut varieties are slightly more drought tolerant and may be favored in strip-till or no-till systems.

Late-Winter Work

• Planting method and timing—Red clover can be broadcast into winter wheat just before green-up while the ground is still frozen and fields are fit to drive on. The freeze-thaw action will work the seeds into the ground. (See Underseeding Red Clover into Winter Wheat in Resources.)
• Seeding rate for red clover—Broadcast red clover at a rate of 7–9 lbs/acre. For more information, see Agronomy Guide for Field Crops (in Resources).

Summer Work

• Scouting—Look for red clover plants to have about 5 leaves during late May before the dry summer period.
• Wheat harvest—Harvest wheat at the normal time. The red clover will continue growing until terminated.