Covering new grass seed protects it from birds, wind, and drying out while it germinates
New grass seed needs protection during the first two to three weeks while it's sprouting. The main threats are birds eating the seed, wind blowing it away, heavy rain washing it downhill, and the soil surface drying out too fast. A cover holds moisture in the soil, keeps birds off, and anchors the seed in place. The right cover lets water and air through, so the seed can still germinate underneath.
You have several practical options, and the best one depends on how much area you're seeding, your budget, and how much time you want to spend. Some covers are temporary and you remove them once the grass sprouts. Others break down on their own or stay in place as the grass grows through.
Key Takeaways
- Straw is the most common cover for grass seed because it's cheap, lets water through, and you rake it off once the grass is a few inches tall.
- Erosion control blankets (also called coir mats or jute netting) stay in place as the grass grows through them and eventually decompose, so you don't have to remove them.
- Burlap works well for small areas and slopes because it's heavy enough not to blow away and you can reuse it year after year.
- Peat moss and compost hold moisture but can crust over and block seedlings, so they work best mixed into the soil before seeding rather than laid on top.
- Never use plastic sheeting—it traps heat and moisture and will kill the seed by creating a greenhouse effect.
Straw: the standard choice for most homeowners
Straw is the most widely used cover for grass seed because it's inexpensive, available at garden centers and hardware stores, and does the job well. A layer one to two inches thick lets water and light through while keeping the soil from crusting over and drying out too fast. It also makes it harder for birds to reach the seed.
The main drawback is that straw often contains weed seeds. Buy weed-free straw or erosion control straw if you can find it—it costs a bit more but saves you from fighting weeds later. Spread it loosely so you can still see the soil underneath in places; if it's packed too thick, it can smother seedlings.
Once the grass reaches two to three inches tall and has a few blades showing, rake the straw off or leave thin patches of it to decompose. If you leave too much straw in place, it can mat down and block the new grass from growing upright. Most people remove most of it and let the rest break down naturally over a few weeks.
Erosion control blankets for slopes and problem areas
An erosion control blanket (also called a coir mat, jute netting, or coconut fiber mat) is a biodegradable fabric designed to hold soil in place on slopes while seed germinates. It's made from natural fibers like coconut husk, jute, or straw that are woven or matted together. The blanket stays pinned down with landscape staples, and grass grows up through the openings in the weave.
This option is best for steep slopes, areas prone to washout, or places where wind is a real problem. Because the blanket stays in place, you don't have to come back and remove it—it breaks down over three to six months as the grass establishes. You pay more upfront (typically $0.50 to $2 per square foot, depending on the type), but you save labor.
Install it by unrolling it over the seeded area, overlapping edges by four to six inches, and securing it with landscape staples every two to three feet. Water it the same way you'd water bare soil—the fabric lets water through. Once the grass is established and the blanket starts to break apart, you can leave the pieces in place or rake them out.
Burlap for small areas and reusable coverage
Burlap is a heavy, woven fabric that works well for small seeded areas, around trees, or on slopes where you need something that won't blow away. It's breathable, lets water through, and you can reuse it year after year. Lay it loosely over the seeded area and weight it down with rocks, landscape staples, or soil at the edges.
Check under the burlap every few days—once you see green shoots, remove it so the grass can grow upright. If you leave it on too long, the grass will grow pale and weak underneath. Burlap is more work than straw because you have to monitor it and remove it by hand, but it's a good choice if you're seeding a small patch or want to avoid weed seeds from straw.
Peat moss and compost: better mixed in than laid on top
Peat moss and compost hold moisture and can be worked into the top half-inch of soil before you spread seed. This approach is gentler than laying a thick cover on top, because it doesn't risk smothering seedlings. Mix peat moss or finished compost into the soil at a ratio of about one part amendment to three parts soil.
If you do lay peat moss or compost on top of seed as a cover, keep the layer very thin—no more than a quarter-inch. Thicker layers can crust over when they dry, creating a hard shell that seedlings can't push through. Water it lightly and often to keep it from crusting. Most homeowners find straw or a blanket easier to manage than trying to keep peat moss at exactly the right moisture level.
What not to use: plastic and other mistakes
Never cover grass seed with plastic sheeting, landscape fabric, or any material that doesn't let water and air through. Plastic traps heat and moisture underneath, creating a greenhouse effect that cooks the seed or causes it to rot. It also blocks light, which some grass seeds need to germinate.
Avoid using hay instead of straw—hay is dried grass and clover that's full of viable seeds, so you'll end up seeding your lawn with whatever was growing in the field the hay came from. Don't use sawdust, wood chips, or bark mulch; they tie up nitrogen as they break down and can slow germination. Don't cover the seed so thickly that you can't see any soil—the cover should be light enough that seedlings can push through.
How long to leave the cover in place
Most covers stay on for two to three weeks, which is roughly how long it takes cool-season grass (like fescue or bluegrass) to sprout. Warm-season grass (like zoysia or Bermuda) can take three to four weeks. Check under the cover after two weeks—if you see green shoots and the grass is starting to fill in, it's time to remove or thin out the cover.
If you're using straw, rake most of it away once the grass is two to three inches tall. If you're using burlap, remove it completely. If you're using an erosion control blanket, you can leave it in place and let it decompose, or remove it once the grass is established. The goal is to get the cover off before the new grass gets so tall that it flattens under the weight of the cover material.
Watering under the cover
Keep the soil moist (not soggy) while the seed is germinating, even with a cover in place. The cover helps hold moisture, but it doesn't eliminate the need to water. Water lightly and often—usually once or twice a day for the first two weeks, depending on temperature and rainfall. If the weather is hot and dry, you may need to water more often.
Water in the early morning so the soil has time to absorb moisture before the heat of the day. If you water in the evening, the soil stays wet overnight, which can encourage fungal problems. Lift the cover in a corner occasionally to check that the soil underneath is moist but not waterlogged. Once the grass is up and growing, you can water less often but more deeply.
Frequently Asked Questions
Can I leave straw on the lawn permanently?
No—straw left in place will mat down, block sunlight, and prevent the new grass from growing upright. Remove most of it once the grass reaches two to three inches tall. You can leave thin patches to decompose, but rake off the bulk of it within three to four weeks.
Do I need to cover grass seed if it rains a lot?
Rain helps keep the soil moist, but it doesn't protect seed from birds or prevent erosion on slopes. A light cover is still worth using because it anchors the seed and reduces the chance of washout. You may be able to use a thinner layer than you would in a dry climate.
What if I can't find weed-free straw?
Regular straw contains weed seeds, but you can still use it if that's what's available. Just be prepared to pull weeds as they come up during the first few weeks. Many of the weeds will die off once the grass is established and shading the soil, so it's not a permanent problem.
Can I use newspaper or cardboard as a cover?
Newspaper and cardboard break down too slowly and can create a barrier that blocks water and air. They also tend to blow away or get soggy and fall apart. Stick with straw, burlap, or an erosion control blanket for better results.
Should I cover the seed if I'm seeding in fall?
Yes—fall seeding still needs protection from birds and wind, and a cover helps hold moisture during dry spells. Fall rains are usually more frequent, so you may not need to water as much, but the cover is still useful. Remove it once the grass is established, before winter dormancy sets in.