Answer: I would consult with your local county extension to determine the best way to change the pH of your soil and verify that you really need to do that to grow whatever it is you have in mind. This is usually a long term project that requires repeated testing and fine tuning. You also want to avoid shocking any existing plants that are happy with the soil as is. Most plants are able to grow in a range of pH conditions, so you would only need to work on acidifying if you want to grow something with a very specific need for acid soil (such as blueberries or azaleas.) One easy way to increase acidity or decrease alkalinity is to avoid applying lime to your lawn or garden area. Lime is used to raise pH and has a long lasting effect. If this is the cause of the alkalinity then you would basically just wait a few years for the effect of the lime to leach out of the soil naturally. But again, your county extension should be able to help you with what to use and how much at a time to use depending on your native soil and what you need to achieve. I hope this helps.
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