Calculating lawn fertilizer Question

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So my soil sample came back and reported I need per 1000sqft
2-4lbs N per 1000 sqft
2lbs P per 1000 sqft
2lbs K per 1000 sqft

They also recommend this to be applied by 1/2 for 2 feedings.

So i figured just go with
N 2lbs
P 1lb
K 1lb

Now I have 18,000 sqft what is a easy method to figure out how much fertilizer I need?
 
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If you use a 10-10-10 fertilizer to add 2 lbs N, 2 lbs P, 2 lbs K per 1,000 ft2:
you need to use 20 lbs of fertilizer per 1,000 ft2 or 360 lbs of fertilizer per 18,000 ft2.

If you have another fertilizer in mind, I can recalculate that for you no problem.
 
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If you use a 10-10-10 fertilizer to add 2 lbs N, 2 lbs P, 2 lbs K per 1,000 ft2:
you need to use 20 lbs of fertilizer per 1,000 ft2 or 360 lbs of fertilizer per 18,000 ft2.

If you have another fertilizer in mind, I can recalculate that for you no problem.
Thank you Seems like a lot, maybe you can make better sense of it with the results
786D1545-468C-484C-8367-812D80331FA0.png
 
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Yes it did sound like alot to me too. I'm not a grass man, I grow vegetables. The soil tests around here don't test for nitrogen and looks like yours didn't either. I assume its because the nitrogen evaporates before being tested, not real sure. I guess maybe you can ask for it but I never have. Maybe they assume it is negligible?

Those values are in parts per million. If you want to convert to pounds per acre, mutilply ppm x 2.

For lawns I see it commonly recommended to add 1 lb of N per 1,000 ft2 which equates to 44 lbs of N per acre.

So looking at your test without knowing your nitrogen content and assuming you can add 44 lbs N/acre, you can add 10 ppm P (20 lbs P/acre) & 60 ppm K (120 lbs K/acre).

My math:
200 lbs of 10-10-10 per acre equals 20 lbs/N/acre -20 lbs/P/acre - 20 lbs/K/acre
192 lbs potassium nitrate per acre equals 25 lbs/N/acre - 0 lbs/P/acre - 85/K/acre
--------------------------------------------------------------------------------
total = 45 lbs/N/acre, 20 lbs/P/acre, 105 lbs/K/acre


Now break this down to 18,000 square feet (what you need) you need to add:
83 lbs of 10-10-10 and
80 lbs of potassium nitrate

Nitrates flow with water and will wash out of the soil with enough rain so I'm not sure if that is the perfect choice of fertilzer but as far as matching numbers goes, that is about as perfect as it gets.

If you want to just do a 10-10-10 fertilizer, I'd throw out 100 lbs per 18,000 ft2 and get a soil sample next year. Looks like your on the verge of adding a little bit of dolomite lime which will also raise the pH, but I don't know how much.
 
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Well for some reason I didn't see the bottom section of the report till afterwards. It says you should use 75 lbs of limestone per 1,000 ft2 but not to add more than 50 lbs/1,000 ft2 until you test again, basically next year.

And it is recommending to add about 3 lbs N, 1.5 lbs P, 2 lbs K per 1,000 ft2 or 54 lbs N, 27 lbs P, 36 lbs K per 18,000 ft2.
So if you do a 10-10-10 fertilizer and use 270 lbs per 18,000 ft2 of it, it will add 25 lbs N, 25 lbs P, 25 lbs K per 18,000 ft2 and it recommends breaking that up into 3-4 times this year.
 

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