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  • How to Correct Alkaline Soil (pH 8 and above)

    Created by Rodney Boerm on

    Everything in my yard is yellow in color, with a ph meter my soil tests at 8 and sometimes higher. What can I do to amend this soil? I’ve applied Ironite® and it hasn’t changed anything. The trunks of my trees are growing very quickly, but are light yellow-green. What’s the answer to lowering it?

  • Author
  • #177408

    Eric Vinje

    Rodney –

    Naturally-occurring elements push soil toward either end of the scale. Forested areas with plenty of rainfall like the East Coast and the Pacific Northwest tend to have acidic readings (4.0- 6.0), while the low-moisture Mountain West trends alkaline (above 7.5). The Midwest is generally neutral, with readings between 6.0 to 7.5.

    Most plants have adapted to a wide pH range, and some even prefer environments that lean one direction. Blueberries, azaleas and rhododendrons are acid-loving, and clematis, lilac and peony prefer to be on the alkaline side.

    When your garden is in that neutral sweet spot (7.0), essential elements like nitrogen, phosphorus, potassium, iron and manganese dissolve easily, which lets the roots deliver them quickly and easily to your plants.

    To lower your soil pH from 8.0 to 7.0 we recommend adding elemental sulfur, sometimes called split- pea sulfur at a rate of 10 lbs. per 1,000 sq. ft. You can also add plenty of compost — especially if you have poor soil conditions — to help neutralize pH.


    Hope this helps!

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