When to Apply Milorganite Before and After Rain for Best Results?

Are you looking for a natural fertilizer alternative that can help your morganite grass thrive? Milorganite could be the right solution for you. This organic-based fertilizer is made with microbes, which helps plants absorb the nutrients they need and offers protection against pests. In this blog post, we’ll discuss what Milorganite is, when to use it for best results, and how it can benefit your lawn. Read on to learn more about this powerful but organic lawn care option so that you get maximum value from its use in your garden.

Basics of Milorganite


Milorganite contains the following nutrients:

  • 6% Nitrogen (N)
  • 4% Phosphorus (P)
  • Less than 1% Potassium (K)
  • 2.5% non-staining Iron

In addition to these primary nutrients, Milorganite also contains various micronutrients in trace amounts that contribute to the overall health of your lawn.

Manufacturing Process

Milorganite is derived from the wastewater treatment process in Milwaukee, Wisconsin. Microbes consume the organic matter in wastewater, and once they’ve fully processed the organic materials, the remaining material is kiln-dried and packaged as Milorganite.

How Milorganite Works on Your Lawn

Milorganite is a slow-release fertilizer, meaning the nutrients are not immediately available for plant uptake but are released slowly over time. This gradual release reduces the risk of over-fertilization, burn, and nutrient leaching while supporting consistent growth and maintaining a healthy lawn.

Comparing Milorganite to Traditional Fertilizers


  • Environmentally friendly: Milorganite repurposes a waste product, making it a sustainable and eco-conscious choice for lawn care needs.
  • Slow-release: The slow-release nature of Milorganite ensures a gradual nutrient supply to your lawn, reducing the risk of over-fertilization or nutrient runoff.
  • Iron content: The 2.5% non-staining iron helps maintain a deep green color in your lawn.
  • Reduced odor: Compared to some other organic fertilizers, Milorganite has a less intense odor.


  • Lower nutrient content: Milorganite has lower nutrient percentages than some synthetic fertilizers, which may require more frequent applications for similar results.
  • Availability: Milorganite may not be available in all areas or may be subject to occasional supply shortages.

Ideal Time and Frequency

Application rates and timings may vary depending on location, soil type, and lawn health. In general, it is recommended to apply Milorganite 4 times per year, with specific guidelines for different regions:

When to Apply: Milorganite Schedule to the Lawn

Cool-Season Grass ApplicationWarm-Season Grass Application
Memorial Day (mid- to late-May)Easter (after turf breaks dormancy)
July 4th (mid-summer)Memorial Day (mid- to late-May)
Labor Day (early-September)Labor Day (early September)
Thanksgiving (mid-November AFTER lawn is dormant and BEFORE first frost)Early October (or when overseeding)
Memorial Day (mid- to late-May)Easter (after turf breaks dormancy)

Always conduct a soil test before applying fertilizer to determine your lawn’s nutrient needs and tailor your Milorganite application accordingly.

How Many Bags of Milorganite Need Per Acre?

Your Yard SizeNumber of Milogranite Bags
2,500 sq feet1
1/4 acre5
1/3 acre6
1/2 acre9
2/3 acre12
3/4 acre13
1 acre18

Best Ways To Milorganite And Water Lawn

  • Application rates: Follow the manufacturer’s recommended application rates, typically 32 pounds per 2,500 square feet.
  • Spreader settings: Use a broadcast or drop spreader for even application; consult the Milorganite website for specific spreader settings.
  • Watering: Water your lawn after applying Milorganite to help the fertilizer move into the soil – about 0.25 inches of water is sufficient.
  • Mowing: Make sure to mow your lawn before and after applying Milorganite so the fertilizer has contact with the soil.
  • Storage: Store unopened bags of Milorganite in a cool, dry place, away from direct sunlight.

Additional Tips

  • Before applying Milorganite fertilizer, mowing your lawn to enhance soil contact is recommended.
  • To ensure an even application, apply half of the recommended amount in one direction and the remaining half in the opposite direction.
  • Milorganite provides a list of popular spreaders and settings for your convenience, but if your spreader is not listed, you can easily calibrate it using our recommended instructions.
  • Your walking speed can affect application rates – walking steadily is advised.
  • Unlike synthetic fertilizers, Milorganite does not require watering, although watering or rain can expedite the release of nutrients into your lawn.
  • If you can only fertilize once a year, the optimal time is in the fall.

Health and Safety Considerations

Milorganite is safe for use on turf grass but may not be suitable for edible plants. Additionally, due to the high nitrogen content, it is not recommended for use on turf grass that is less than 3 months old. Always read and follow all label instructions when applying any fertilizer.

By following these tips and understanding how Milorganite works, you can keep your lawn looking its best without sacrificing the health of your plants or the environment. With a comprehensive understanding of Milorganite and how it works, you can create an ideal lawn care regimen that meets your needs without compromising quality.

The key to using Milorganite effectively is consistency. Apply it regularly throughout the year to ensure a healthy lawn season after season. For more information on Milorganite, consult your local lawn care expert. With the proper knowledge and care, you can keep your lawn looking vibrant and healthy all year.


Milorganite uses natural ingredients to provide slow-release, consistent nourishment to your lawn without risking the health of your plants or environment. With proper application and regular maintenance, you can enjoy a beautiful green lawn year after year.

By understanding the benefits and drawbacks and following recommended guidelines when applying Milorganite fertilizer, you can be confident that you are taking the best care of your lawn.

If you have any questions about the best way to use Milorganite for your lawn, don’t hesitate to contact a local lawn care specialist who can provide expert advice and guidance tailored to your needs. With the proper knowledge and regular maintenance, you can create an ideal healthy, vibrant lawn environment.

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