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View Full Version : soil samples, how often?


Branchland
02-24-2006, 07:39 AM
How often do you do soil samples? Every year, two years, just once? I do it every couple of years, just wondering how often yall do them. :)

upidstay
02-24-2006, 09:07 AM
Our rainfall is pretty acidic here in CT, as we get all of the smokestack emissions from across the country as they blow over here, plus a billion or so cars. I like to test soil every year. I also like to lime every year, at least a maintenance dose (10-15lbs/k) but I am one of the few who do that.

thomsoutdoor
02-24-2006, 09:12 AM
I like to do it every year and Maryland Law requires it every two. Note that if you pick up a TruGreen customer that the ph is usually high seeing that they lime no matter what.

muddstopper
02-24-2006, 06:35 PM
I like to do it every year and Maryland Law requires it every two. Note that if you pick up a TruGreen customer that the ph is usually high seeing that they lime no matter what.

I doubt that the lime is what is raising the Ph levels, altho it certainly isnt helping. The More likey cause is the amount of fertilizers Truegreen is adding to the soil. Urea nitrogen, MOP all high sodium content which contributes to raising the soil Ph. excess nitrogen acgtually leaches the calcium from the soil. Think about it for a minute. They apply 1lb of nitrogen perM 4-5 times a year. Thats 174 lbs on nitrogen to a crop that if managed properly probably wouldnt use 30lbs of nitrogen. Even if the Clippings are removed from the lawn, 80 lb N would be more than adequate. That leaves 100lb +/- nitrogen that the plants arenot using. That nitrogen has to go somewhere. If the soil doesnt have enough microbes to mineralize the N then it converts to ammonium gas or Nitric acid. The nitric acid leaches off from the soil carrying the Calcium with it. As the Calcium is leached from the soil the magnesium levels rise. Magnesium will raise PH more than Calcium so the Ph starts rising. Since the Ph is now high, it takes more nitrogen just so the plants can takeup what they really need. Again The nitrogen rate results in leaching and calcium loss. Magnesium, Potassium, and Sodium will all raise soil Ph. Any excess the plants dont need will result in higher than necessary Ph, low calcium levels as well as tie up other necessary plant nutrients.