Establishing a healthy stand of clover, whether for pasture, hay, or cover cropping, requires precise calculation of seed needed per acre. The standard measurement for this rate is expressed in pure live seed (PLS) pounds, which accounts for both the germination percentage and the physical size of the seed. Achieving the correct density is critical; too little seed leads to sparse growth and weed invasion, while too much wastes capital and can create overly dense stands that are prone to disease.
Understanding Pure Live Seed (PLS)
The most important concept in determining how much clover per acre is the Pure Live Seed (PLS) calculation. Because seed bags contain inert material that does not grow, the listed weight alone is misleading. PLS factors in the germination rate, which is legally required to be printed on the label, to determine the actual weight of viable seed. For example, a 50-pound bag of clover with a 90% germination rate contains 45 pounds of PLS. You must always base your seeding rates on the PLS value to ensure you are placing the correct amount of genetic material into the ground.
Species and Variety Differences
The specific type of clover you select dramatically impacts the seeding rate required per acre. Large varieties like Mammoth Clover or Alsike Clover produce massive seeds that require more space to develop robust root systems, typically necessitating higher PLS pounds per acre. Conversely, small-seeded varieties like Crimson or White Clover require less physical seed weight to achieve ground coverage. Furthermore, breeding advancements have led to different growth habits—some varieties are more erect while others are vining—which influences how densely they can be planted without competing for light.
Typical Seeding Rate Ranges
When planning your planting schedule, you will encounter a range of recommendations depending on the clover type and the time of establishment. Drilling clopper into a prepared seedbed generally requires a higher PLS rate than broadcasting into existing sod. The following table outlines the common PLS seeding rates for popular clover types:
Seeding Method and Environment
The method you use to distribute seed is a major variable in determining the final rate. No-till drilling into wheat stubble or using a frost-seeding regimen into frozen pasture sod requires less seed than traditional deep tillage and seedbed preparation. The contact between the seed and soil is vital for germination; if the seed is not placed at the correct depth—inadequate coverage leads to drying out, while too much soil buries the seed too deeply—establishment rates plummet. In competitive grass pastures, you might increase the rate by 20% to ensure the clover can compete for sunlight and nutrients during the critical juvenile phase.
