Using seeding straw is a common and cost-effective method for establishing a new lawn or repairing bare patches. This organic material protects the newly sown grass seed and the soil surface during the critical germination phase. Proper application creates an ideal microclimate for the seeds, significantly boosting the chances of developing a healthy, uniform lawn. Understanding the correct material and application technique is necessary for establishing dense turf.
Distinguishing Seeding Straw from Hay
Selecting straw rather than hay is the first important step. Straw is composed of the hollow, dried stalks of cereal grains like wheat, oats, or barley that remain after the grain heads have been harvested. Because the grain has been removed, this material is typically seed-free.
Hay, conversely, is made from the entire flowering body of grasses and legumes, such as alfalfa or clover, which are cut and cured for animal feed. Hay bales are filled with seeds that will germinate alongside the grass seed, resulting in unwanted weeds. To prevent this contamination, look for “weed-free” or “erosion control” wheat or oat straw, which is usually bright golden in color and lightweight.
The Purpose of Using Straw Over Seed
Seeding straw functions as a temporary, organic mulch that creates a stable environment for grass seed germination and initial growth. Its primary function is moisture retention, as the light layer acts as a natural barrier to slow water evaporation from the soil surface. This is crucial because grass seeds require constant moisture to sprout successfully.
The straw also provides temperature moderation for the soil beneath it. It helps keep the soil slightly cooler during intense sun and prevents heat loss during cooler nights, supporting germination. Furthermore, the straw physically protects the newly planted seed from environmental stressors like heavy rainfall and strong winds. The material absorbs the impact of raindrops and holds the seeds in place, preventing soil erosion.
Step-by-Step Application Technique
After the grass seed has been spread, the straw should be applied immediately for protection. A typical small square bale can cover approximately 1,000 square feet, but coverage varies based on density. Before application, break apart the tightly bound bale, separating the compressed material into loose strands to ensure even distribution.
The most important step is to spread the straw in a thin layer, aiming for 70% to 80% coverage of the soil and seeds. This application should look like a light dusting, where you can easily see the soil through the straw. Apply the loosened straw by hand, using a gentle broadcasting motion to scatter the material evenly across the seeded area.
Applying the straw too thickly is a common mistake that can smother emerging seedlings by blocking sunlight and restricting airflow. The goal is to create a thin, consistent layer that protects the seed without inhibiting its access to light and air. For areas with steep slopes or high wind exposure, consider using a straw blanket or erosion control netting, which is stapled into the soil for additional stability.
Watering and Post-Germination Care
The initial watering immediately after applying the straw settles the material and helps it adhere to the soil, preventing it from being blown away. Since straw retains moisture, watering frequency is dictated by the need to keep the top inch of the soil consistently moist, not saturated. During germination, this may require frequent, light waterings, possibly several times a day in hot or windy conditions.
As the grass seedlings emerge, the straw is generally left in place if applied thinly. Since straw is organic, it will naturally break down, adding organic matter to the soil as the lawn establishes itself. If the straw was applied too thick and impedes growth, gently rake away some material using a flexible plastic leaf rake once the grass blades reach one to two inches in height. Avoid disturbing the young, fragile root systems of the new turf.