You have taken a soil sample to your local extension agent or garden center or you purchased a home soil test kit or instrument to test the ph of your soil. The results indicate your soil is acidic. Congratulations! Most plants do their best in soils with a ph reading of neutral or slightly acidic. Your yard will have various readings from area to area; the backyard may have slightly acidic soil while the side yard may have high acidity. It is important not to assume your various planting areas all have the same reading.
Ph (potential of hydrogen) indicates a soil's ability to control nutrients needed for a plant to grow and strive. If the ph is too high or two low, nutrients will be confined and not released for the plant to consume. A reading of 7.0 is neutral. Less than 7.0 indicates acidity in your soil and can range from 6.5, slightly acidic, to 4.0 and under which is highly acidic. On the other side of the neutral marker, over 7.0 indicates alkaline soil. Most plants prefer soils with a ph reading of 6.5-7.0, slightly acidic to neutral.
Plants for high acidic ph soil conditions: (4.0-5.5):
Plants for strong acidic ph (5.0-5.6 )or acidic (5.6-6.0):
• Hydrangeas (if you want blue flowers)(pink flowers in alkaline soils)
• Witch hazel
Plants for slightly acidic ph to neutral ph (6.5-7.0):
• Most vegetables like squash and cantaloupe
• Most fruit-strawberries sweeter in acid soil
Plants that would do better in alkaline soil rather than acid soil:
• Bearded irises
• Lilac shrubs
• Sea grape
• Mock Orange
If you are not sure of a plant's ph requirement after you have placed it in the ground, watch for signs of leaves yellowing. This can indicate the roots are not getting the nutrients they need due to too much acidity or not enough.
Too raise the acidity level and lower the ph in your soil, add materials such as peat moss, aluminum and iron sulfate or sulfur, composted oak leaves, wood chips and leaf mold. To lower the acidity and raise the ph, add lime, ashes of hardwoods, crushed marble or oyster shells or bone meal. Ph will not change quickly but several factors can change your readings from season to season such as soil amendments applied, watering with city water and acid rain. It is best to gradually change ph and check your soil readings each season.