Alkaline soils can be acidified with a solution of 1 tablespoon white vinegar per gallon of water used as a soil drench.
To determine the alkalinity of your soil, GardenZeus recommends the following articles:
Down and Dirty 5: What is the Mother of All Southern California Landscape and Garden Problems?
Down and Dirty 7: Mud Pies and Fizz: Easy Home Tests for Soil pH
Down and Dirty 8: Tips for Soil Testing Soil pH at Home with a Soil pH Meter
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