Milorganite as topdressing test

Discussion in 'Turf Renovation' started by RigglePLC, Jan 10, 2018.

  1. dKoester

    dKoester LawnSite Gold Member
    Messages: 3,419

    Its what I use as well. LOL
    kevin_dreamlawnsva likes this.
  2. RigglePLC

    RigglePLC LawnSite Fanatic
    Messages: 13,931

    The cups are about 2.25 inches in diameter--if that helps your calculations.
    What if the bags are only a half-cubic foot in volume?
    The Milorganite bags weigh 36 pounds.

    Oddly, the tallest sprout was in the Milorganite-treated cup, about 5 inches, but there were only 7 sprouts. The untreated soil tallest sprout was about 4 inches. The untreated had more germination and sprouts--about 10 sprouts.
    Both 11 days old.
    Actually an online source said bulk density was 40 to 45 pounds per cubic foot.
    I estimate one bag per thousand sqft is very near 1/8 of an inch deep. The granules would not form a uniform coating. Roughly, perhaps averaging, 1/8 inch deep.

    Last edited: Jan 13, 2018
    dKoester likes this.
  3. KerbDMK

    KerbDMK LawnSite Senior Member
    Messages: 768

    Thanks Riggle, with the diameter of the cups that you provided, I have calculated Milorganite’s recommended seeding rate of 72 pounds per 2500sf to equal 0.4515 grams per cup. My kitchen scale only measures down to one whole gram, so I weighed out one gram of Milorganite and it filled one level teaspoon, so use one half of a teaspoon per cup for Milorganite's recommended seeding rate.

    Ironicly one whole teaspoon of Milorganite granules looks to me to just about cover a 2.25 inch circle in a single layer, but that is twice the amount recommended for seeding.
  4. KerbDMK

    KerbDMK LawnSite Senior Member
    Messages: 768

    I did a little more tinkering with my scale because I don’t trust trying to weigh such a small amount at a time. I weighed 6 teaspoons (two tablespoons) of Milorganite and it weighed 24 grams and I repeated that two more times. That came close to your 6 teaspoon per ounce calculation (there are actually 28.8 grams in an ounce).

    So it seems that going by 24g = 6tsp, 4g= 1tsp, 1g=1/4tsp, 0.5g=1/8tsp. So actually you need to use just 1/8tsp to get the recommended seeding rate for Millorganite.

    The accuracy of our scales and even the accuracy of our volume measurements are really important in such small scale experiments. I have noticed from experience that teaspoon measures seem to vary by manufacturer and the quality and accuracy of electronic scales also varies. That makes it very difficult to do these kinds of experiments.

    Going by weight would seem to me to be the most accurate way to measure fertilizer. We just need a scientific scale accurate enough to measure down to centigrams or milligrams.

    The math says you need 0.4515g per cup and according to my scale and my teaspoon measures you need 1/8 tsp/cup but your scale and measures may vary. Lol.
  5. KerbDMK

    KerbDMK LawnSite Senior Member
    Messages: 768

    Sorry, I relied on my memory again and I should never do that. An ounce is actually 28.35 grams but that error did not affect my calculations.

    Is anybody bored or confused yet?
    hort101 likes this.
  6. dKoester

    dKoester LawnSite Gold Member
    Messages: 3,419

    That ruler says grow with the forest. LOL! That one piece of grass took the advice from the ruler. That's funny.

Share This Page