Will Grass Seed Germinate on Top of Soil? (When Not Covered?)

It’s quite challenging when growing grass from seed, you may not be sure whether to cover the seeded lawn or just leave them scattered on surface of soil. This guide has all answers to that. So, will grass seed germinate on top of soil?

Yes, grass seed can germinate on top of soil. However, it’s usually beneficial to cover them with a fine layer of topsoil, compost or mulch. It help to keep the soil moist, promote even germination, reduce seed movement and encourage development of roots as well as deterring birds from feeding on seed.

Will Grass Seed Germinate on Top of Soil?

It’s not ideal to simply spread grass seed on top of soil and leave it to germinate. Yes, some of the seeds may germinate and grow without further steps but you will end up with poor and uneven germination. Grass seed are vulnerable to different elements if not covered.

Germination of grass seed take 3 to 4 weeks. During this period, they require favorable soil conditions to germinate. The process of germination require air, optimum temperature and appropriate amount of moisture. These conditions are effectively achieved when seeded lawn area is covered.

When grass seed are not covered, the newly germinated seedlings will struggle to get properly rooted. It may also predispose the seedling to harsh environmental conditions. When the roots are too shallow into the ground, they prevent the grass from obtaining water and nutrients that are below the surface.

Exposing grass seed on top of soil create an easy source of food for birds. Different birds like sparrows, finches, starling and blackbirds eat grass seed as part of their diet. Covering them with mulch or soil can help to hide the seed from hungry birds.

Leaving seeded lawn uncovered also increases the chances of seed being carried away by wind or surface runoff from a heavy downpour. Remember that it take up to 4 weeks for grass seed to germinate. Therefore, you need to keep them in one place until they germinate.

Why should you Cover Grass Seed?

It is essential to cover your seeded lawn with fine soil, compost or mulch. It help to promote even and proper germination. If you want your seed to germinate properly, you have to create favorable soil conditions such as right temperature and amount of moisture. All these can be achieved when the seeded lawn is covered. Other benefits of covering grass seed include:

1. Healthy Development of Roots

Seeded lawn that is covered with soil, compost or mulch is likely to develop healthier roots as compared to when scattered on the surface of the soil. Grass require a deep web-like rooting system to develop and grow healthy. The plant is also able to get necessary water and nutrients that are deeper into the soil.

2. Even Germination of Seed

When you place seed on ground without covering, it simply mean that it will only receive moisture from one side while the other side will be drying out in the sun. Grass seed require moisture, warmth and air on both sides to germinate evenly.

3. Deterring Birds from Pecking on the Seed

Birds like finches, sparrows and starlings eat grass seeds as part of their diet. These birds will feed on the seed if they get them uncovered on ground. Covering seeded lawn with compost, mulch or soil will help to deter birds from pecking on the seed.

4. Reduced Seed Movement

Grass seed are tiny particles that are easily carried away by wind or runoff from rainfall or watering. If they are properly secured with a layer of soil or mulch, the movement is greatly reduced. Therefore, it help to promote even germination.

5. Protection from the Sun

Covering a seeded lawn help to protect the seed from scorching effect of sun. Grass seedling are quite delicate, can easily dry out when exposed to high temperatures from the sun.

6. Conservation of soil Moisture Content

Covering grass seed with straw mulch help to lock water in the soil by reducing rate of evaporation. It greatly reduce the frequency of watering. You’re only required to keep on checking the soil moisture content and water when soil feel dry.

How to Tell if Grass is Germinating

To tell if grass seed is germinating, you have to understand the germination process in the first place. Germination is simply the initial growth process that take place when seed absorb enough moisture to start sprouting. Grass seed will take 3 to 4 weeks to germinate if the soil conditions are favorable.

Seed germination process require three basic conditions that include air, warmth and moisture. Light is also necessary once the seed have germinated. Let’s have a look at each of them:

Air or Oxygen

When seedling sprout through the seed coat, they require oxygen to grow and develop. If soil is saturated with moisture but lack air, the sprout will simply dye. This problem is usually common with compact clay soil. Adding compost into the soil before planting can help to aerate the soil.


Soil temperature is supposed to be within appropriate range to initiate germination process. Warm-season grass require soil temperature range of 55 – 70 degrees Fahrenheit while cool-season grass prefer 45 – 55 degrees Fahrenheit. Be sure to check soil temperature and not air temperature prior to planting your seed


Moisture is also a necessary condition for germination process to take place. The seed absorb sufficient moisture to soften the seed coat before sprouting. Moisture must be adequate throughout the process. If water is too little, the seed will dry out and stall germination process. On the other hand, excess water can cause the seed to rot.


Light is essential for healthy growth of grass seedling. The seed may fail to germinate in shady areas of your lawn. Cloudy weather can also lower soil temperatures. This can have a negative impact on germination of warm-season grass. Ensure the seeded area receive adequate amount of sunlight.

What to do if Grass Seed doesn’t Grow

There are various factors that can cause poor or failed germination. They include: Inadequate soil moisture, poor quality seed, wrong temperature, inadequate sunlight, lack of nutrients in the soil, unsuitable soil pH, presence of weed killers in the soil, traffic on a newly seeded area and improper seed-to-soil contact.

So, what do you do if grass seed doesn’t grow? It is important to start by diagnosing the issue to find exact cause and solution to it. The following tips can help to initiate germination process of dormant seed.

1. Keep Soil Moist

The seeded area must be kept moist for germination to take place. Prior to planting your seed, the soil should be moist for at least 6 inches deep. Water again for about 5 minutes after spreading the grass seeds on the ground. Water twice daily until the seeds germinate. The soil must be kept moist for at least 1 to 2 inches deep during the entire germination process.

2. Check Soil Temperature

Grass seed won’t grow if the soil temperature is wrong. Different types of grass require different temperature range to germinate. Warm-season grass require soil temperature of at least 55 – 70 degrees Fahrenheit while cool-season grass prefer a soil temperature range of 45 – 55 degrees Fahrenheit.

3. Test soil pH

Grass seed will not grow if the soil pH is incorrect. If you have tried everything but still your grass fails to grow, it’s high time to check soil pH. Grass grows best in soil with a pH range of 5.8 – 7.2.

4. Fertilize Soil

Grass seed require adequate nutrients to grow and develop. Apply a fertilizer rich in nitrogen and phosphorus to stimulate shooting and proper roots development. New lawn require these nutrients to kick-start their growth.

5. Keep Off Newly Seeded Area

Reduce traffic on a newly seeded ground for at least 4 weeks. Wet soil together with grass seed can stick on the soles of your shoes and be carried away. Grass seedlings are also very delicate, a simple step on them can easily kill them. It’s also important to limit pets, stray dogs and cats from accessing the new lawn.

6. Cover Grass Seed

Grass seed may fail to germinate if they are not covered well with soil or mulch. Uncovered seed are also vulnerable. They may be eaten by birds, blown away by wind or swept away by surface water run-off. Be sure to bury seed for ¼ inch deep into the soil or cover them with a layer of mulch.

7. Use High Quality Seed

Grass seeds won’t grow if you planted poor quality seeds. When shopping for grass seed, be sure to check the package for expiry dates. Try to check the price tags also, it’s not always a good idea to buy a product with the lowest price. It may have some short-comings.

Final Thoughts

Now that you know it is essential to cover a seeded lawn with a layer of topsoil, compost or mulch. Next time you sow your grass seeds, be sure to cover them to promote even germination, healthy root development, conserve soil moisture content, prevent seed movement as well as from being eaten by birds.

Leave a Comment