Straw, mulch, and burlap are the three main covers that keep grass seed moist and protected while it germinates
Covering grass seed protects it from birds, wind, and drying out during the critical first two weeks when it's sprouting. The best cover depends on your lawn size, budget, and how much work you want to do. Straw is the cheapest and most common choice for large areas. Mulch works well for smaller patches and blends in better once the grass grows. Burlap is the most labor-intensive but gives you the most control and looks neater during the waiting period.
The cover doesn't have to stay on forever—you remove it once the grass is tall enough to mow, usually three to four weeks after seeding. The goal is straightforward to hold moisture in the soil and keep the seed from washing away or blowing around while the roots establish themselves.
Key Takeaways
- Straw is the cheapest option for large lawns and works well, but you need to rake it out carefully to avoid smothering new grass.
- Mulch (wood fiber or compost-based) stays in place better than straw and breaks down into the soil, though it costs more per square foot.
- Burlap or erosion cloth pinned down gives you the most control but requires removing pins and rolling it up once grass reaches two inches tall.
- Never use hay instead of straw—hay contains weed seeds that will sprout alongside your grass.
- The cover should be thin enough that light reaches the soil; too thick and you'll block germination instead of protecting it.
Straw: the budget choice for large areas
Straw is the most affordable cover and works well for seeding large sections of lawn. It's the dried stalks left over after grain is harvested, and it's light enough that water and air still reach the soil underneath. A thin layer—roughly one-quarter to one-half inch—is enough to shade the seed and hold moisture without blocking light.
The main drawback is that straw can be uneven. Some areas end up too thick and smother the seedlings; others too thin and don't protect the seed. You'll also need to rake it out once the grass reaches two inches tall, which is labor-intensive on a large lawn. Straw can also blow around in wind before it settles, so water it lightly after spreading to help it stay in place.
Buy straw from a garden center, farm supply store, or online. A typical bale covers 1,000 to 2,000 square feet depending on how thickly you spread it. Check the label to confirm it's straw, not hay—hay contains weed seeds and will create more problems than it solves.
Mulch: slower to decompose and easier to control
Mulch made from shredded wood fiber or compost works better than straw if you want a neater appearance and don't want to rake as much later. It stays in place better in wind and won't blow around as easily. The downside is that it costs more per square foot than straw and takes longer to break down into the soil.
Spread mulch to a depth of one-quarter inch—thicker than straw, but still thin enough to let light through. It will gradually decompose over several months, which means you won't have to remove it entirely. Once the grass is established and you start mowing, the mower will break up any remaining mulch and work it into the soil.
Mulch works especially well for small seeding jobs, patchy repairs, or areas where appearance matters while the seed is germinating. It also helps retain moisture longer than straw, which is useful in hot or dry climates. Buy it bagged from a garden center or in bulk from a landscape supplier.
Burlap and erosion cloth: maximum control and neatness
Burlap and erosion cloth (also called coir matting or jute netting) give you the most precise control over coverage and the cleanest look while the seed is growing. These materials pin down flat over the seeded area, so nothing shifts or blows away. Light and water pass through, and you can see exactly where the grass is sprouting.
The trade-off is labor. You'll need to pin the material down with landscape staples every few feet, and then remove all the pins and roll it up once the grass reaches two inches tall—usually two to three weeks after seeding. On a large lawn, this becomes a significant job. Burlap also costs more upfront than straw.
Burlap works best for small to medium areas, slopes where erosion is a concern, or situations where you want to avoid the mess of straw or mulch. Erosion cloth is thinner and more durable than burlap; it's designed to stay in place longer and can handle heavier rain without tearing. Both are available from garden centers and online suppliers.
How thick to spread your cover
The most common mistake is covering too thickly. A thick layer blocks light and prevents the seed from germinating, defeating the whole purpose. Aim for these depths: straw one-quarter to one-half inch, mulch one-quarter inch, and burlap or cloth pinned flat with no gaps.
You should still be able to see patches of soil through the cover. If the ground is completely hidden, you've applied too much. A light cover is enough to shade the seed, reduce evaporation, and keep birds from pecking at it. Once you've spread it, water lightly to help it settle and stay in place.
When to remove the cover
Leave the cover in place for two to four weeks, depending on temperature and moisture. In warm weather with regular watering, grass germinates faster and you can remove the cover sooner. In cool weather, it takes longer.
The signal to remove it is when the grass reaches two inches tall. At that point, the seedlings are strong enough to handle sun and wind without the cover's protection. If you leave it on too long, the grass will start to yellow and weaken from lack of light.
For straw and mulch, rake it out gently or leave thin patches to decompose naturally. For burlap and cloth, remove all pins and roll it up carefully so you don't disturb the new grass. Once the cover is off, water as needed to keep the soil moist until the grass is established—usually another two to three weeks.
Frequently Asked Questions
Can I use hay instead of straw?
No. Hay contains weed seeds that will sprout alongside your grass and create a weedy lawn. Straw is the dried stalks without the seed heads. Always check the label or ask the supplier to confirm you're buying straw, not hay.
What if I don't cover the seed at all?
Uncovered seed is vulnerable to birds, wind, and drying out. You'll likely lose a significant portion of it, especially in the first week. Covering increases your germination rate and gives you a fuller lawn with less waste.
Can I use newspaper or cardboard instead?
Newspaper and cardboard don't work well because they block water and air from reaching the soil, and they break apart quickly when wet. Straw, mulch, or cloth are designed to let moisture and oxygen through while still protecting the seed.
Do I have to water if I cover the seed?
Yes. The cover reduces evaporation but doesn't eliminate it. Water lightly and frequently—usually once or twice daily—to keep the soil moist (not soggy) during germination. The cover helps, but it doesn't replace watering.
What's the difference between erosion cloth and burlap?
Burlap is thicker and breaks down faster, usually within a few weeks. Erosion cloth is thinner, more durable, and can stay in place longer without harming the grass. Erosion cloth is better for slopes or areas with heavy rain; burlap is fine for flat lawns and works faster if you want to remove it sooner.