Should You Put Lime Down Before Sod If the pH Is High?

Soil pH

• Applying lime without understanding the basics of the pH range results in unhealthy sod growth and future problems. Soils with a pH range of 7.0 to 9.0 are too alkaline, and a pH of 5.9 or below are too acidic to support grass growth. Your pH range is highly influenced by where you live in the country. For example, southeastern soils tend to fall within a range of 4.0 to 8.0, according to Clemson University. Testing your soil will give you a better idea of what soil amendments if any to spread.

Testing the Soil

• While there are plenty of soil tests available at gardening supply centers, gardeners will get the most accurate soil analysis from their cooperative extension office. To send a soil sample to your local cooperative extension office, dig 10 holes in the landscape. Holes should be 4 to 6 inches in depth. Collect 1/2 a cup of soil from the bottom of each hole. If the soil is moist, dry the sample out on plastic before placing in a bucket. Mix the bucket of soil samples and pour 1/2 cup of soil in a container. Mail the container to your local cooperative extension office.

Adding Sulfur

• Gardeners that have a high pH range should lower their range, so that it falls between 6.0 to 7.0 using elemental sulfur. The amount of sulfur you apply depends on your existing range. For instance, soil that has a pH range of 8.0 should apply .3 lb. of sulfur per 10 square feet to achieve a 6.5 pH, according to Iowa State University. Water the soil after applying the sulfur.

Fertilizer

• Gardeners should apply a starter fertilizer on the soil after amending their high pH with sulfur. Use a starter fertilizer that is high in phosphorous. You can use 20 lbs. of fertilizer per 1,000 square feet that has a NPK amount of 5-10-5 or 5-20-10, according to the University of California. Work the starter fertilizer into the first 2 to 4 inches of top soil. Water the yard and install your sod. Fertilize and test your soil pH again in six weeks.