How to Get Acidic Soil for Azaleas
- 1). Test the soil determine its pH level. Soil test kits are available at garden stores or at offices of local university cooperative extensions. Follow the directions provided. Many samples are sent to labs for analysis.
- 2). Analyze the results of the soil test. A pH level of 7 is neutral. Soil pH levels above 7 are alkaline, while levels below 7 acidic. Aazaleas grow best in soils with a pH level of 5 to 5.5, according to the University of Missouri Extension.
- 3). Add amendment materials to lower the soil's pH level if the results show a level greater than 5.5. Add sphagnum peat, elemental sulfur, aluminum sulfate, iron sulfate, acidifying nitrogen and organic mulches to lower a soil's pH level, suggests the Iowa State University Extension.
- 4). Add lime, such as calcitic lime or dolomatic lime, to raise the alkalinity of soil with a pH level of less than 5. Avoid hydrated lime, the strongest type available, except in heavy clay, as its has a tendency to burn plant roots. Wood ashes also can be used to raise alkalinity, but more than 2 lbs. per 100 square feet of soil can create high potassium levels.
- 5). Till the soil to a depth of 6 inches. Alkaline soils should be amended a year before planting time, while acidic soils can be amended anytime, according to the University of Minnesota.
- 6). Add the chosen amendments to the tilled soil. The amount of product used will depend on what product is used. Consult the amendment material's packaging or the local cooperative extension for amendment ratios.
- 7). Till the amendment materials into the soil. Soak the soil to its saturation point, when water just begins to pool on the surface. Use a garden hose with an adjustable nozzle on a gentle spray setting to avoid over-watering. Saturating the soil helps amendments to merge with the soil.
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