Clover is a widely utilized legume valued for its ability to fix atmospheric nitrogen into the soil, naturally fertilizing subsequent crops. The required amount of clover seed per acre varies significantly, depending on the specific species chosen and the intended agricultural application. This variability ensures the stand establishes successfully and meets the goals of the planting.
Primary Variables Affecting Clover Seeding Rates
The final seeding rate is influenced by three major factors that govern plant competition and establishment success. The purpose of the planting is a significant variable; for instance, high-yield forage production requires a much denser stand than planting for green manure or soil improvement.
The method used to plant the seed also plays a large role. Broadcasting, which involves scattering the seed over the soil surface, generally requires a 20 to 30% higher seeding rate compared to drilling. This increase compensates for less precise seed placement and reduced seed-to-soil contact.
Finally, the existing soil and climate conditions must be considered. Planting into poor quality soil, or in an area prone to dry conditions or heavy weed pressure, may necessitate a slightly higher rate to ensure successful establishment. Conversely, planting in an ideal, well-prepared seedbed with optimal moisture allows for the use of the lower end of the recommended rate ranges.
Standard Seeding Rates for Pure Clover Stands
When clover is planted as a single species, or a “pure stand,” the seeding rate is maximized to achieve the highest possible density.
Red Clover
Red Clover (Trifolium pratense) is a common short-lived perennial often used for hay and pasture. The standard pure stand seeding rate is 8 to 12 pounds per acre. Broadcasting may increase the rate to 12 to 15 pounds per acre, while drilling can use the lower range of 6 to 8 pounds per acre.
White Clover
White Clover (Trifolium repens) is a lower-growing, long-lived perennial primarily used for grazing and lawns due to its creeping growth habit. Because the seeds are very small (over 750,000 seeds per pound), a full stand requires a significantly lighter rate. Typically, 2 to 8 pounds per acre is used for a pure stand, with some varieties requiring only 2 to 4 pounds per acre.
Crimson Clover
Crimson Clover (Trifolium incarnatum) is a fast-growing annual popular as a cover crop for quick nitrogen fixation and forage. Due to its relatively large seed size, the pure stand rate is higher, generally falling in the range of 15 to 30 pounds per acre. A drilled stand may use 15 to 18 pounds of pure live seed (PLS) per acre, while broadcasting requires 20 to 30 pounds PLS per acre.
Alsike Clover
Alsike Clover (Trifolium hybridum) is a short-lived perennial preferred for its tolerance of wet or acidic soils. As a pure stand, the typical seeding rate is 8 to 10 pounds per acre. This clover is often planted with grasses in areas with poorly drained soil.
Adjusting Rates for Mixed Pastures and Cover Cropping
When clover is introduced into a mixture, the pure stand rates are significantly reduced to account for competition from companion species. For Pasture Mixes containing clover and grass, the clover seeding rate is often lowered to 2 to 5 pounds per acre, regardless of the clover type. For example, Red Clover may be reduced to 3 to 6 pounds per acre, and White Clover to 1 to 3 pounds per acre, allowing the grass component space to establish.
Cover Crop Blends with grains or brassicas also use reduced rates, often planting the clover at 40 to 60% of its normal monoculture rate. A typical mix might involve 8 to 12 pounds of Crimson Clover paired with 30 to 40 pounds per acre of a cereal grain like rye. This adjustment ensures the grain provides quick erosion control and acts as a nurse crop without outcompeting the clover.
A successful stand requires Seed Inoculation with the correct strain of Rhizobium bacteria. This treatment is necessary for the plant to fix nitrogen and is a prerequisite for achieving the full benefit of any seeding rate.