What are signs my soil is too acidic?
Written by
Benjamin Miller
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Observing plant signs is the first way to recognize overly acidic soil. Your garden will send out unmistakable distress signs when its pH is too low. Acidity becomes a problem in soil with a pH under 5.0. Low acidity can lead to nutrient deficiencies, as plants cannot effectively absorb various minerals critical to their health. Once you identify the signs of acidic soil, you can take corrective measures to address the issue.
Leaf Discoloration
- Yellowing between veins while veins stay dark green
- Purple tint developing on leaf undersides
- Brown edges appearing on older leaves first
Growth Issues
- Stunted plants failing to reach expected size
- Reduced flowering despite proper sunlight
- Poor fruit set even with adequate pollination
Nutrient Problems
- Blossom end rot in tomatoes from calcium deficiency
- Iron toxicity causing bronze leaf speckling
- Aluminum toxicity damaging root systems
Weeds have great potential as natural indicators of soil acidity. For instance, both sorrel and plantain prefer relatively high acidity. When moss is found covering large areas of soil, it implies a low pH. Pine trees will make the surrounding area more acidic in nature. These physical clues provide a basis for observing a plant's symptomatic stage, serving as a proper indicator of diagnosis.
Testing your soil gives you definitive confirmation. You can purchase DIY test kits from your local garden center. You can send samples to your state's cooperative extension service, which will provide complete analyses. You should test multiple areas of your garden, as the pH varies across your landscape. The test results will help you identify the best corrective measures.
Correcting acidic soil can be accomplished gradually. Finely ground limestone can be used to increase pH levels. While powdered lime will work, pelletized limestone will react faster. Wood ash will add potassium and decrease acidity. Always follow the instructions on the package rate to avoid over-correcting.
Prevent potential acidity issues in the future by adopting some smart practices. Rotating lime applications every two to three years in problem areas can help mitigate acidity. Refrain from over-applying acidifying fertilizers. Assess your pH at least once per year, or conduct an annual test. Practicing these approaches can maintain a balanced state for a variety of plants.
Read the full article: 10 Acidic Soil Plants That Thrive
