LAWN & GARDEN > How To Take a Soil Sample

How To Take a Soil Sample




The first thing you must know to collect a proper soil sample is the depth the sub- samples should be taken. The following table gives you recommended sampling depths for common landscape areas.

Recommended Sampling Depths
Established lawns 2-4 inches
Vegetable and flower gardens 6-8 inches or tillage depth
Trees and shrubs 6 inches


Sample depths are measured from the soil surface downward. For lawns, sample to a depth of 4 inches, excluding any turf thatch. For vegetable and flower gardens, sample to the depth that you plan to incorporate lime or fertilizer, usually 6 – 8 inches. In mulched beds of trees and shrubs, remove any mulch or surface debris, then sample to a depth of 6 inches.

When sampling soil around established trees and shrubs, take sub- samples from an area near the trunk to the outer edges of the branches (the drip line). For a particular landscape area, it is best to use the same sampling depth from year to year so soil test values can be more accurately compared.

How to Take Soil Samples:

STEP 1: Open a hole with a hole with a shovel, spade or trowel from the surface to the proper depth for your landscape area. Set that soil aside. *If you are using a soil probe, insert it into the soil to the proper depth and remove the plug from the ground.

STEP 2: With your shovel or trowel, remove a 1 X 1 X 4 inch slice from the smooth side of the open hole.

STEP 3: Remove the top surface of grass, litter or any rocks. Place in clean bucket. Never use a metal container to hold your samples. Remember that a clean, plastic container is best.

STEP 4: Depending on the acerage, take the recommended amount of sub-samples from different locations within each uniform sampling area to make a composite sample. Take the sub-samples in a random manner, such as with a zigzag pattern to minimize the variability that may be present in your sampling area. This allows you to obtain a reasonably representative soil sample. See diagrams below.


Recommended Sample Rate
0 - 1/4 acre Minimum of 5 samples
1/4 acre - 1/2 acre 5 - 15 samples
1/2 acre - 1 acre 15 - 20 samples

STEP 5: Place all the samples for one unique area in a plastic bucket and mix thoroughly. Use the mixture in the bucket to fill a soil sample bag two-thirds full. Look for the fill line on the bag (can be obtained at any Mill location).

Soil samples are $15.00 per sample bag.