Soil pH Levels

Garden soil tests will tell you the pH level of your garden. If a soil test indicates that your soil is very acidic, consider growing acid-loving plants, or try ground limestone to raise the pH. Limestone is nature's soil sweetener, capable of neutralizing overly acidic soils. It's best to add limestone in the fall to allow time for it to begin to dissolve and do its job. The amount of limestone you use will vary depending on the specific soil conditions. Don't dump limestone on soil randomly, because you run the risk of overdosing the soil with lime. Follow guidelines on the limestone package or on your soil test. Maintaining the new and improved pH is an ongoing project. Recheck the soil's pH every year and continue to add limestone as needed.

If, on the other hand, your soil test shows that your soil is on the alkaline side, add cottonseed meal, sulfur, pine bark, compost, or pine needles. Garden sulfur is a reliable cure when added as recommended in a soil test. It acidifies the soil slowly as microbes convert the sulfur to sulfuric acid and other compounds. Soil amendments such as compost, decaying pine bark, and ground-up pine needles gradually acidify the soil while improving its texture.

Composting is an inexpensive and organic way to add nutrients to your garden soil. Keep reading to learn how to compost.

Sources of Specific Nutrients
Many of these fertilizers are available processed and packaged. You don't have to harvest your own.
  • Nitrogen: bat guano, blood meal, chicken manure, cottonseed meal, fish emulsion, kelp meal, livestock manure (composted)
  • Phosphorus: bonemeal, rock phosphate, super phosphate
  • Potassium: granite meal, greensand, seabird guano, shrimp shell meal, sulfate of potash, wood ashes
  • Calcium: bonemeal, chelated calcium, eggshells, limestone, oyster shells, wood ashes
  • Boron: borax, chelated boron, manure
  • Copper: chelated copper
  • Magnesium: chelated magnesium, dolomitic limestone, Epsom salts
  • Sulfur: iron sulfate, sulfur, zinc sulfate
  • Zinc: chelated zinc, zinc sulfate
  • Iron: chelated iron, iron sulfate


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