How to Neutralize Soil Under Pine Trees
Grass and other plants stop growing under a pine tree for two primary reasons. One is the shade; the other is the extra acidity from pine needles that drop onto the soil and decompose. Grass grows poorly in acidic soil, so you'll have to neutralize the soil under your pine trees. This is easily accomplished by adding an alkaline soil amendment.
Rake all needles, bark and any wood chips from around your tree, using the rake. Needles and wood add acid to the soil under the tree.
Run an aerator under the tree. The aerator should be set to a depth of 1 to 1 1/2 inches. Use care not to damage roots close to the surface. Use the aerator from the tree's drip line in; the drip line is where the tree's longest branches extend to.
Spread lime in the aerated area, using a lime spreader. Use 25 lbs. of lime per 1,000 square feet. A circle with a radius of 10 feet encloses an area of approximately 315 square feet.
Rake fallen pine needles so they do not add new acid to the soil.
Add approximately 25 lbs. of lime per 1,000 square feet each spring, using the lime spreader.
Neutralize Pine Needle Acid In Soil
Send a soil sample to a local extension service to determine the pH of the soil, and how much you may need to increase it and what other nutrients you may need to add to the soil. Purchase a pH-raising material. Hydrated lime will have a rapid effect on pH without the added nitrogen. Calculate the area of ground to be covered. For a square or rectangular plot of ground area is length times width.
Wear a breathing mask when spreading lime.
Consult with your local nursery to determine the best shade-tolerant grass for your area.
- Wear a breathing mask when spreading lime.
- Consult with your local nursery to determine the best shade-tolerant grass for your area.
- Lime spreader
- Walter Reeves: Lawn: Growing in Shade
- Golf Link: How to Plant Grass Under Pine Trees
- USDA Forest Service: Effect of Ponderosa Pine Needle Litter on Grass Growth
- University of Wisconsin Extension: Pine Needles Cause Acid Soil – Fact or Fiction
- Colorado State University Extension: Turf Myths: The Truth Shall Set You Free
- Mississippi State University Extension Service: Soil pH and Fertilizers
- University of Florida Cooperative Extension Service: pH Problems Produce Peaked Plants
- Fine Gardening: Pine Needles in the Compost