Will Fungicide Kill Grass Seed?

Fungicide will not harm grass seed or newly sprouted grass. In fact, applying fungicide at the time of seeding or germination can help to protect new grass from fungal diseases. If you notice fungal diseases in your newly seeded lawn, act quickly to use a fungicide designed to control the disease. You won’t put your new lawn at any risk—in fact, you may save it. Always make sure to follow the bag directions whenever you are applying fungicide.

Will fungicide kill grass seed?

Can You Put Fungicide Down With Grass Seed?

You can apply fungicide at the same time you spread grass seed without any problem. Fungicide doesn’t affect grass seed germination or growth. If your lawn is currently suffering from a fungal disease, it’s a great idea to treat your yard with fungicide at the same time you apply new grass seed. This will help to prevent the fungus from attacking your new seeds and grass.

  • You can safely spread fungicide in the same area where you have spread grass seed.
  • Fungicide will not prevent grass seed germination and growth.
  • Spreading fungicide on new grass seed helps to kill Phomopsis sp., a seed-attacking fungus.

One great reason to apply fungicide along with your new seed is to kill and prevent fungus that specifically attacks seeds, such as Phomopsis sp. This fungus preys on seeds and will interrupt proper germination. Using a fungicide while seeding works to kill this fungus so your new grass seed sprouts in greater numbers.

Can You Use Fungicide on Grass Seedlings?

It is safe to use fungicide on new grass seedlings. If there is lawn rust, dollar spot, or any other type of fungus attacking your new grass, use fungicide promptly to kill the fungus before it does extensive damage to your lawn. You won’t harm your grass or interrupt grass growth as long as you are using fungicide according to the manufacturer’s instructions.

  • You can safely treat grass seedlings with fungicide.
  • Always apply fungicide at the rates recommended by the manufacturer.
  • Use this lawn spreader to spread fungicide, seed, and fertilizer in separate passes.

Fungicide is very flexible and works well with other lawn treatments. In the right conditions, you may even be able to apply fertilizer and fungicide at the same time. However, it’s best to apply seed, fertilizer, and fungicide in separate passes with a lawn spreader. Applying seeds and lawn treatments separately allows you to fill your lawn spreader with the bag-recommended amount of the substance, which ensures you’ll get even lawn coverage.

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Should Grass Seeds Be Treated With Fungicide?

It is not required for you to treat grass seeds with fungicide, but using fungicide can actually boost grass seed growth in some cases. If your lawn or region is prone to fungus, your seeds and seedlings can be attacked and killed quickly, which will result in fewer sprouts. Even worse, some grass seeds can carry fungus and introduce it to your yard. Using fungicide after seeding can help prevent both these problems.

  • Fungicide can help some grass seeds, but it is not required to treat all grass seeds with fungicide.
  • Fungicide applied after seeding can protect your seed from lawn diseases or kill any fungus currently infecting the seeds.
  • This Propiconazole-based fungicide promotes germination and establishment of some grasses.

Fungicide containing Propiconazole can be very beneficial to some grasses. In addition to killing fungus, Propiconazole aids in the establishment of cool-season grasses. So, if you are growing a cool-season type of grass, such as Kentucky Bluegrass, Rye, or Fescue, fungicide can make your seedlings healthier at the same time it protects them from disease.

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Does Fungicide Slow Grass Growth?

Fungicide does not affect grass growth. So, your grass will not grow slower or faster due to fungicide treatment. Lawn fungus can lead to dead grass and large brown patches throughout your lawn. So, if you’re battling lawn diseases, don’t hesitate to use a lawn-safe fungicide. It won’t slow down the germination or establishment of new grass seedlings. It also won’t negatively impact the growth of mature grass.

  • Fungicidal applications do not slow down grass growth.
  • Both new and established grass growth cycles are unaffected by lawn fungicides.
  • Identify your lawn fungus if possible, to help select the best fungicide for the job.

It can be hard to tell whether you are battling a lawn fungus or if your grass is struggling due to other reasons. Before you spend money on fungicide, attempt to determine whether your lawn has a common fungal disease, such as dollar spot fungus. The more you know about the disease, the easier it will be to select the proper treatment.

Can Too Much Fungicide Kill Grass Seed?

Overusing fungicide can harm grass seeds, seedlings, and established grass plants. Too much fungicide can burn grass, which may kill seeds as they attempt to germinate. Additionally, applying too much fungicide on your lawn can kill soil microbes. Without these microbes, your grass plants will struggle to pull in nutrients. Soil ravaged by fungicide overload cannot support a healthy lawn.

  • Applying too much fungicide can kill grass seeds and plants.
  • Too much fungicide can burn and dry out grass leaf blades.
  • Overusing fungicide can destroy the soil microbes that keep your lawn healthy.
  • Review and follow all fungicide application directions.

Whenever you apply fungicide to your lawn, follow the instructions included on the fungicide packaging. This includes application rates as well as application frequency. Spreading too much fungicide at once—or applying fungicide too frequently—can result in dry, brown grass.

Can You Use Disease EX With New Grass Seed?

You can safely use Scotts Disease EX right after seeding. Disease EX won’t harm grass seed, seedlings, or established lawns. So, if your lawn is battling a fungal disease or you believe your grass seed may be carrying fungus, apply Disease EX just after seeding. This can help to control fungus so it does not spread to your new grass.

  • It is safe to use this Scotts Disease EX fungicide on new grass seed.
  • Disease EX won’t harm grass at any stage of life.
  • Take note: the frequent watering grass seed requires may wash Disease EX off your lawn.

One risk of applying Disease EX to new grass seed is that the fungicide may be washed away quickly. This is because new grass seed requires frequent watering. Disease EX does not need to be watered in and should be left to absorb for 1–2 days. It is not possible to go 1–2 days without watering your new grass seed, so Disease EX may be more effective on established lawns.

Does Fungicide Affect Seed Germination?

If you are unsure whether to apply fungicide to a newly seeded lawn, review these facts:

  • You can safely apply fungicide to your lawn any time after seeding.
  • Lawn fungicide won’t harm grass seed, seedlings, or mature grass.
  • Fungicide does not slow grass growth.
  • Using fungicide on newly seeded lawns can help kill seed-carried fungus.
  • Follow manufacturer instructions—using too much fungicide can kill grass and seeds.
  • Because new seed requires frequent watering, fungicide is more likely to be washed off newly seeded lawns.

Using fungicide as soon as a fungal disease is apparent is one of the most essential lawn care practices. The right fungicide can stop fungus from spreading to your new grass, or stop fungus on your grass seeds from spreading to the rest of your lawn.

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