What do you Put down First – Grass Seed or Fertilizer?

Starting a new lawn grass from seed require careful preparations to encourage even germination and proper growth. Grass seed need a starter fertilizer to boost their initial growth. However, you may not be sure what to put down first. So, what do you put down first, grass seed or fertilizer?

Fertilize an area to be seeded before putting down seed. Grass seed are vulnerable, they require proper soil conditions to germinate and grow. Fertilizing soil help to make it rich and fertile for the incoming new seed. It also ensure nutrients are readily available to grass seed and seedlings.

Grass Seed or Fertilizer First?

It’s essential to fertilize soil before planting grass seed to establish even germination and proper growth. Adding nutrients into the soil will ensure newly germinated seedlings have what they need to grow properly. For better results, there are various recommendations to follow before fertilizing and sowing grass seed.

1. Conduct a Soil Test

Before doing anything on the site, conduct a soil test to determine pH and nutritional condition of the soil. Performing a soil test will tell the exact nutrients that are inadequate and the proportions required. You do not want your new lawn to miss out on critical nutrients such as nitrogen and phosphorus in their initial growth stage.

2. Clear and Till the Site

Clear the site to remove small bushes, dead plants, sticks, stones and other debris. Use a hoe to till the land up to a depth of 6 inches. Break up the large clods of soil and grade the area to ensure its sloping away from buildings in your compound. Be sure the area is even by filling dips with soil. The soil should be loose to allow easy penetration of roots.

3. Amend the Soil

Add organic materials into the soil to improve fertility, drainage and aeration. Apply at least a 2 inch layer of well-rotted compost on the surface of the soil and in-cooperate it into the soil for about 6 inches. Be sure not to use fresh compost or manure that may introduce weed and diseases into your garden.

4. Correct the Soil pH

Adjust soil pH as needed by adding lime or sulfur. Most grass varieties thrive and establish well in soil with a pH of 6.0 to 6.8. If the pH is high or low follow the recommendations provided by soil test results. If the pH is too high, apply sulfur to bring it down within recommended range. On the other hand, apply lime if the pH is too low.

5. Fertilize the Area

Apply starter fertilizer before planting the seed. If you conducted a soil test, apply according to recommendations provided. Select the best fertilizer that suit your soil nutritional need.

Generally, you can apply 1 pound of starter fertilizer per 1,000 square feet area. Use slow-release fertilizer since it release nutrients slowly and longer as required by plants. Choose a fertilizer that doesn’t contain herbicides. It can prevent grass seed from germinating.

6. Rake and Sow Grass Seed

Rake the area to obtain a smooth and fine soil particles. Remove sticks, rocks and other debris that may have remained in soil. Apply grass seed on soil surface as recommended on the package. Use an empty roller to gently firm the soil. Alternatively, you can cover the seeded area with a layer of mulch. Lastly, water your seeded lawn.

How long after fertilizer can you put down grass seed?

You can plant grass seed immediately after fertilizing the area. The initial fertilizer will help to feed the grass seed as they germinate. Since you’re watering regularly to keep the soil moist during germination period, nutrients may leach out of the soil relatively fast.

Therefore, you’re required to fertilize your seeded lawn with a second round of starter fertilizer after 4 weeks of seeding. The fertilizer will continue to boots germination and growth of seedlings. Application rate should be according to recommendations provided on the package.

If you’re using a fertilizer product containing herbicides, you have to wait for longer before planting grass seed. Such products are ideal for killing weeds while promoting growth for an established lawn and should not be used on a seeded lawn.

Weed-and-feed products should never be applied immediately before or after seeding. They contains herbicides that kill grass seedling or prevent germination from taking place. If you applied fertilizer containing herbicides, wait for 8 weeks before planting grass seed. You should also wait for the same period of time before using these products on your new lawn grass.

Will Fertilizer Kill Grass Seed?

Yes, using regular fertilizer instead of a lawn starter can kill grass seed. Regular fertilizers doesn’t contain enough phosphorus needed by newly germinated grass. Instead, it will suffocate grass seedlings with excess nitrogen and potassium that are not necessary in the initial growth stage.

Some regular fertilizers also contain herbicides or pre-emergent to control crabgrass and other weeds in your lawn. They’re ideal for an established lawn. Such fertilizers can disrupt seed from germinating when used on seeded lawn.

Herbicides or better known as pre-emergent are made to prevent germinating seed from establishing roots. However, these herbicides cannot distinguish between harmful weeds and desirable seeded lawn. Although they are aimed at killing broad leaves weeds they can injure immature grass seedlings.

Be sure to follow manufacturer’s instructions when using fertilizers containing herbicides. Generally, you should refrain from applying fertilizers containing herbicides 6 to 10 weeks before or after planting new grass seed.

It’s also important to conduct a soil test prior to applying fertilizer to determine the type of nutrient that are inadequate and the quantities required. Generally, starter fertilizers should be applied at 0.5 – 1 lb. nitrogen per 1,000 square feet of lawn. Applying excess nitrogen fertilizer can burn and kill your newly germinated grass seedlings.

Final Thoughts

 It’s recommended to apply fertilizer first before sowing grass seed. It’s also ideal to conduct a soil test so that you are able to select a suitable starter fertilizer. The results will indicate pH and the level of nitrogen, phosphorus and potassium needed by the soil for a healthy growth and establishment of your new lawn grass.

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