Autumn is the Time to Lime

Posted: September 22, 2012

Liming an acid soil creates a favorable soil environment in which plants can thrive...

Autumn is in the air. The vegetable garden is winding down, the summer flowers are fading, and it is time to think about applying lime. The benefits of applying lime are many and long term.  Liming an acid soil creates a favorable soil environment in which plants can thrive. When the soil pH is raised by liming, soil nutrients are made more available for plant uptake. Typically when we see a micronutrient deficiency in a plant, it is not because there is not enough of the nutrient in the soil, it is because the soil pH has limited the availability of that nutrient. 

Why lime in autumn? It takes time for lime to react with the soil and for the benefit to occur. Liming this fall will result in your soil’s pH being in the ideal range next summer.

Which is better: pulverized or pelletized? It depends on what type of spreader you use. Pelletized is made to work best with a spinner spreader, while pulverized works best in a drop spreader. I spread mine by hand so I buy what is cheapest.

Lime supplies calcium and magnesium to the soil. Calcium is critical if you want to avoid blossom end rot on tomatoes. Tree fruit is also very sensitive to shortages of calcium. Lime is the most inexpensive way to supply these nutrients. It is classified as either high calcium or high magnesium lime. High calcium lime contains 3% or less magnesium. How do you know which type of lime you need? The soil test results will tell you. Most of our soils need high calcium lime.

How do you know if your soil would benefit from liming? Get a soil test done. Testing the pH and nutrient levels of your soil is the only way to know for sure what is really happening. Often problems arise from nutrients being out of balance. Applying more of a nutrient than a plant needs or less than it needs creates imbalances that need to be corrected for optimum plant health. Soil test results not only tell you what you need to apply, but can also let you know when you have over-applied nutrients. Over application not only hurts the plant, but also creates a situation where nutrients can be lost into the environment where they can be detrimental. A soil test kit can be purchased from your county’s Penn State Extension office for a cost of $9.00.

If you are growing plants that prefer an acid soil do not lime the soil around them. Lime can severely hamper the health of plants like blueberry, azalea, and rhododendron. These plants often benefit from a light application of sulfur which pushes the soil pH lower where they like it. How do you know if you need to apply sulfur to your acid loving plants? Get a soil test of course.

For more information contact your local extension office. In Lackawanna County call 570-963-6842 or email

John Esslinger, Extension Educator
Penn State Extension