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New - What do the numbers mean? 5-19-0, 9-18-90

Discussion in 'Starting a Lawn Care Business' started by ReefBlueCoupe, Aug 21, 2006.

  1. ReefBlueCoupe

    ReefBlueCoupe LawnSite Member
    Posts: 13

    Not those actual numbers, but I see the same algorythm refered to here quite often when talking about putting different things down on the grass. What do they mean?

    Thanks :)
  2. Scotts' Yard Care

    Scotts' Yard Care LawnSite Senior Member
    Posts: 343

    those numbers mean nitrogen, phosphorous and potassium. Basic chemicals that help, respectively, green lush growth, root feeding and all around healthy thickness of the lawn.
  3. ReefBlueCoupe

    ReefBlueCoupe LawnSite Member
    Posts: 13

    Thanks for that info.

    What's an example of a given lawn's problem, and what combination of those chemicals you would use to help correct it?
  4. Scotts' Yard Care

    Scotts' Yard Care LawnSite Senior Member
    Posts: 343

    I'm not into the chemical side of the business but I'll give you my best understanding and let the real experts correct me:) Most chemical companies rely waaaaay too much on nitrogen which does give the quick green up but can severely stress the lawn. I compare this to an athlete who chugs down the steroids; great in the short term but very bad in the long run. Light nitrogen app under 80 degrees should be fine. If I had a lawn that was thin and not tolerant of dry conditions I'd look to the last two numbers to get the the roots strenghthened and to promote thickening of the turf. Of course any pesticide or herbicide application requires a license, insurance and very strict care in use if you're doing it commercially. Your own place is still free from legalisms at least for the moment but care to follow directions should be used.
  5. grass_cuttin_fool

    grass_cuttin_fool LawnSite Gold Member
    Posts: 3,503

    Lets say you have a 50 pound bag of 10-10-10 fert. It stands for 10% of Nitrogen, 10% phos, and 10% potassium. which would be 5lbs of each with 35 pounds of filler with no value. Some one correct me if Im wrong or clarrify it better. This is what I was told years ago at the Farm supply.

  6. ReefBlueCoupe

    ReefBlueCoupe LawnSite Member
    Posts: 13

    Thanks for the info. Just out of curiosity what is the filler usually made of?
  7. Dr Green

    Dr Green LawnSite Member
    Posts: 24

    Let me help.

    everyone is correct in the earlier posts N-P-K

    Again, each number represents a % of the bag . 10-10-10 is 10 % N-P-K and K. In a 50 lb bag, its easy math.

    Now, what most people dont realize is some simple calculations.

    First. Most Fertilizer only products( No combo's like weed and feed) have a recommended setting that is probably tied to 1 # Nitrogen per 1000 sq ft.

    10-10-10 for lawns is not something that is used often, but the numbers are easy to work with.

    In this bag, 10% N is 5 lbs of Nitrogen in that 50 lb bag. At 1# nitrogen per 1000 sq ft, that bag (or recommended setting) will do 5000 sq ft.

    I hear this all the time..."I dont want to use 30-0-15 now. too much nitrogen . have a 20-1-5? "

    A lot of people think they are Juicing the lawn like mad if they use a 30-0-15, but 20-1-5 is OK. They set the spreader at the recommended rate(usually 1#N per 1000). The guy gets 10,000 sq ft out of the 20-1-5
    The other guy gets 15,000 sq ft out of his 30-0-15.

    BOTH PRODUCTS WENT DOWN AT THE SAME NITROGEN RATE. 1# N per 1000 sq ft. The same, but the perception is that the 20-1-5 is better in the summer or heat. Same Stuff here except one bag goes 15,000 sq and another goes only 10,000 sq.

    When you are using combos like Fert/insecticide or weed and feed products,
    the setting or rate is dependent on the Active ingredient per acre or 1000 sq ft of the product on the fertilizer. A Most combination products go down at less than 1#N per 1000 sq because of this. Its fine, but if you live in an area where you need about 4# Nitrogen per 1000 sq ft annually, then if you should be mindful if you are only doing 4 apps. You might need a 5th to get the N you need.

    As far as fillers you usually have other minor nutrients like maybe iron, etc in it too. You can use lime stone, corn cobs, turface as fillers.

    Doesnt really matter. The analysis is the Meat . There is also a huge difference between what is used for the 30% N source etc....some other day on that discussion.

    One more easy tip: If its a 50 lb bag of Straight Fertilizer(no combos), you can easliy know how far any fert goes at the 1# rate.

    32-3-5 goes 16,000 sq. just reduce the Nitrogen content in half (32 here)

    It only works in 50 Lb bags and with fert only products. Active ingredients like weed control and insecticide change the equation.

    Next time you see a 40 lb bag of 27-3-6 that says "covers 17,000 sq ft" you can pretty much tell that its not going down at the 1#N per 1000 that most are trying to achieve.
    You can put anything you want on a bag for coverage! Most dont realize, thats all.

    Now you do.....

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