Lavender pH adjustment – Lavender prefers a pH of 6.9 – 7.2

Curtis Swift, Ph.D., curtis@MesaLavenderFarms.com 979.778.7866

Lavender pH adjustment explains how to determine the amount of liming product to apply per acre.

  1. Select the desire pH level e.g. 7.0
  2. Subtract the buffer pH provided by the soil test report
    1. If no buffer pH is given, then use the pH provided on the soil test
      1. not all laboratories will provide the buffer pH unless you request that.
    2. g. 7.0 – 6.5 (pH on soil test report) = .5
  3. Multiply by 4 (.5 x 4 = 2.0)
    1. This gives you the tons of liming compound based on a neutralizing value of 100 % CCE.
    2. Note: CCE stands for the Calcium Carbonate Equivalent (= neutralizing value)
  4. If you are using calcium carbonate (100% CEC), it will take 2 tons per acre to adjust the pH to 7.0.
    1. To determine the tons of any other product you use, divide the tons of Calcium carbonate required (2 tons) by the neutralizing value of the product.
    2. If using calcium hydroxide (CCE of 135%) multiply 2 tons by 1.35 = 2.7 tons of calcium hydroxide.
    3. If using Magnesium hydroxide, divide 2.0 tons by 1.72 = 3.44 tons.
  5. The finer the product, the quicker the response. Check out https://nrcca.cals.cornell.edu/nutrient/CA5/CA0541.php for more detail.

lavender ph adjustment

Depending on your soil type and rain fall/irrigation, you might need to adjust the pH every few years. A soil test will indicate when the adjustment is necessary.