Sometimes, the lawn is in such bad shape that you can't rescue it. For instance, the lawn could be overcrowded with weeds, full of bare patches, taken over by dead grass, etc.
In these cases, it's better to reseed the whole lawn instead of treating and seeding specific areas. It is also the only option when you want to change the variety of grass.
Reseeding is just like starting over and renovating the whole lawn. It requires a lot of effort, and you have to do everything correctly to achieve excellent results.
This article is a complete guide on how to reseed a lawn. We will help you choose the right time for reseeding and go step-by-step to turn your dead lawn into a lush, green space that is the envy of the neighbourhood.
When is the Best Time to Reseed a Lawn?
Lawn reseeding is a major overhaul, and timing plays a crucial role in defining its success. You can't reseed at any time of the year because you have to consider if the seeds have the right conditions to grow, survive, and turn into healthy grass.
For cool-season grasses, the best time window is early to mid-autumn, which is late August to mid-October. The reason is that these grasses grow aggressively in the autumn. They wake up from summer dormancy and are ready to grow at their peak. Secondly, the conditions are favourable; the soil is still warm, and the air is cooling down compared to summer.
Moreover, the rainfall assists in keeping the seeds moist and increases the chances of growth. And there is minimal competition from weeds.
Another suitable window is early spring, but you have to ensure the grass can fully grow before summer. Secondly, it's also the time for weed seed germination, so you have to be extra careful.
Before planting cool-season grass seeds, you must make sure the soil temperature consistently stays between 10 and 15°C.
Step 1: Get Rid of Existing Grass and Weeds
The first thing you need to do is get rid of all the existing grass and weeds in the lawn.
For weeds, you can use a weed killer. If there are weeds all over the lawn, it is quite helpful in dealing with them. But if there are weeds in a few spots in the lawn, you can pull them out with your hands or spot-treat them instead of using a weed killer on the whole lawn.
After dealing with weeds, it's time for scalping. Mow the existing grass at the lowest lawnmower setting. It will help you get rid of the dead and unhealthy grass blades. After mowing, bag all the clippings and dispose of them properly.
Now, you have to do heavy raking to remove the grass roots and thatch layer. The best way is to use a power scarifier. It will remove everything and leave you with clean soil. But if the lawn is small, you can also use a manual scarifier or rake.
It's necessary to remove the thatch layer, as it won't let your grass seeds reach the soil. Rake heavily and expose the soil as if there were no grass before.
Lastly, get rid of the debris, rocks, roots, and every mess in the lawn. Get it ready for reseeding.
Step 2: Conduct Soil Tests
Before you reseed the lawn, it's advisable to conduct some soil tests. Your lawn has been suffering, and the culprit could be the soil.
When you do lawn soil testing, you get to know about the condition of the soil and whether there are any problems that you have to fix.
The first test is a pH test. Ideally, the soil pH should be slightly acidic to neutral, which means between 6.0 and 7.0. You can use a digital pH probe to test the soil pH. It gives excellent results. However, you can also get an idea through a DIY test kit.
If the soil pH is too low or too high, you need to adjust it. Otherwise, it will cause nutrient lockout. The fertiliser you provide to the lawn will be unavailable to the grass.
The second test is for macronutrients. You need to know how much Nitrogen, Potassium, and Phosphorus the soil contains. If there is any absurd ratio, you can correct it using an appropriate fertiliser.
DIY test kits also give you an idea of the soil macronutrients, but they are not accurate. The best way is to get the soil tested through a lab. It gives you the exact values of the nutrients along with some solutions. You can also get the values of micronutrients in a lab test report.
Another important factor is the Cation Exchange Capacity (CEC) of the soil. It is a measure of how many nutrients the soil can hold. If the CEC value of the soil is too low, the nutrients will wash away, and the grass will not thrive.
The only way to know the CEC value is through a lab report. If the CEC is low, you have to improve the soil components by adding manure, compost, etc. Lab reports suggest what you can add to the soil to improve the CEC value.
Step 3: Opt for Levelling and Soil Improvements
If your lawn has bumps and dips, it's the right time to fix them. You can level the whole lawn, and it not only looks aesthetic but also improves water drainage. Identify the highs and use a shovel to scrape the area. Use the excess soil in the low areas.
Through the CEC test, you might have an idea whether your soil is perfect or contains a higher amount of sand or clay than usual. If the soil is fine, you can skip the following amendments.
To increase the CEC, you can add organic compost to the lawn to a depth of 2.5 to 5 cm. Spread it over the whole area. After that, use a garden rake to mix the compost with the existing soil to a depth of 5 to 8 cm.
Finally, rake the whole area to level everything. You can also use a lawn roller to lightly firm the soil.
Step 4: Aerate the Lawn
Your soil naturally has pores, and these are important for air, water, and nutrient exchange. But over time, soil gets compressed, and these pores are eliminated.
When the soil is too compact, it doesn't let your grass breathe. It will struggle for nutrients and water. And this is when you need to do lawn aeration.
If you have done soil amendments in the previous steps, your soil won't be compact at all. But if you didn't do it, you should test for soil compaction. Use a screwdriver and push it into the lawn. It should glide easily, but if you need to add body weight or pressure to push it to 5 to 7 cm, it means the soil is compacted.
Hollow tining is the best technique to relieve soil compaction. In this process, you remove soil cores from the lawn, and cavities are created. These holes reverse soil compaction and allow the soil to expand.
It's also beneficial for seeding. Because the holes improve the soil-to-seed contact. Secondly, the fertiliser reaches the roots easily.
For hollow tining, water your lawn a day before. Then, use a power aerator to aerate the lawn. If the lawn is small, you can consider a manual hollow-tine aerator.
After aeration, dispose of the plugs. If you want to leave them, just make sure to break them.
Step 5: Select the Seed
Now, it's time to pick the right seed for your lawn. First, you have to decide on the variety of grass you need.
Keep in mind that each grass variety has distinct characteristics. Some are shade-tolerant, while some bear high foot traffic. Some can handle drought, while some are perfect for dogs. You have to pick the right variety according to your lawn.
Step 6: Calculate the Seeds
Once you know the grass variety to go with, calculate the number of seeds you need. Start by measuring the lawn area. If the lawn is big, split it into rectangles and add everything to get the total area.
Check the bag or instructions of the grass seed. It has the appropriate seeding rate, which is in grams per square meter. If the seeding rate is 35 g/m² and the lawn area is 500 m², it means you need 17.5 kg.
Here is a simple formula you can use:
Amount of Seed (kg) = Area (m²) x Seeding Rate (g/m²) / 1000
Step 7: Spread the Seeds
You should use a seed spreader to evenly cover the whole area. Add seeds to the bucket and adjust the dial. Run the spreader on the pavement to adjust the rate.
The best way to spread seeds is using the half-and-half technique. Spread half of the seeds while walking in horizontal lines. Then, spread the remaining half by walking in vertical lines. It allows you to cover every square foot twice.
Step 8: Add a Fertiliser
Seeds need a starter fertiliser. It slowly releases nutrients to the soil, which assists in seed germination and growth. The grass roots go deeper and lay the foundation of a healthy lawn.
We have already tested the soil. If your soil lacks any nutrients, you have a clear idea of what fertiliser to apply. Generally, starter fertilisers have a higher content of Phosphorus, which is the primary nutrient for root development.
Use a broadcast spreader to evenly spread fertiliser in the area just after seeding. Rake the area lightly to mix the fertiliser with the seed and soil. Then, use a lawn roller. It presses the seeds into the soil and improves contact. The chances of germination increase to a great extent.
But make sure to use a light roller or water-filled roller. Do not use an extremely heavy roller, as it can compact the soil. If you don't have a lawn roller, you can rent one.
Step 9: Apply Top Dressing
Top dressing is the protective layer for grass seeds. It does not let water or rain wash them away. It also protects them from birds.
Another benefit of top dressing is moisture retention. It keeps the seeds alive, improves germination, and ensures excellent results.
Coir is the best choice for top dressing. Spread a 0.5 cm layer on the lawn. Other than coir, you can go with compost.
While applying top dressing, you have to be extra careful. If you apply too little, it won't protect the seeds, and if you apply too much, it will block the sunlight. Aim for a light layer, and you should be able to see 10-15% of the bare soil.
Step 10: Ensure Proper Watering
Watering is the key to getting excellent germination rates. The grass seeds are extremely delicate. They need to remain damp in order to germinate. If there is any dry spell, the seeds will die in no time. And then, you can't do anything. Once seeds are dead, they won't germinate.
You have to ensure the top 2.5 cm of the soil stays moist no matter what. Initially, water 2-3 times a day but not deeply. Frequent and shallow watering is recommended.
Once the grass blades start to come out of the soil and reach 2.5 cm, you can reduce the frequency and water deeply.
For more details, check out how long to water new grass seed and how often to water grass seed.
Step 11: Mow Regularly
Initially, you shouldn't mow. Wait until the grass blades reach 9 to 10 cm in height. After the first mow, you need to maintain the optimal grass height according to the variety. And it requires regular mowing.
Always follow the one-third rule for mowing. You should never cut more than one-third of the grass blades at once. Going against the rule means putting the grass under stress.
Before mowing, make sure the grass is dry enough to cut. The blades of the mower should be sharp to cut the grass tips cleanly. Dull blades rip the grass tips and make them vulnerable to diseases.
Mowing regularly is the biggest hassle for lawn owners. They don't get enough time to cut the grass, which leads to overgrowth. To solve this issue, you should adopt a robot lawn mower. It precisely cuts every corner and edge of the lawn, and you don't need to do anything. It automates lawn mowing; all you need to do is set the schedule and mowing height.
Final Words
When you want to start over with your lawn, the best way is to reseed it. It involves removing the old grass, fixing the issues, and planting new seeds. It welcomes new growth and makes your lawn green again. However, it is a detailed and long process that must be done in chronological order. We have explained the step-by-step process to reseed a lawn while addressing the lawn issues. Beginners can also follow the guide and make their lawn lush and green again.
