The wrong pH conditions in lawn soil can make your fertilizing efforts beside the point. This value--a number ranging from 0 to 14--represents how acidic or alkaline a substance is. A pH above 7 means soil is alkaline, below 7 indicates acidity, with 7 being neutral. Most plants like a slightly acidic soil. If plants don't grow in the right pH conditions, they have problems using nutrients. After finding out pH, you will be able to decide if and how you will adjust soil by adding amendments like lime or sulphur.
Contact your local county extension office for a list of testing facilities in your area.
Ask the extension office and/or the testing facility for specific soil collection instructions. Ask also if they have containers to hold the soil you collect.
Gather the appropriate soil sample containers to hold the soil you will bring to the testing facility.
Map out different areas of your lawn, noting areas on hills, midway down hills and in valleys, trouble spots in the lawn, areas that drain and that don't. Depending on the variability of your lawn, you might need several tests, one from each micro-environments.
Push the tube into the soil down to about six inches.
Put the soil into the bucket.
Take about 10 more samples at even intervals around the first site, dumping each into the bucket.
Mix the cores together for your first composite soil sample. Put the soil into the carton to take to the testing facility.
Repeat this procedure at different lawn sites if necessary, dumping each area's cores into a clean bucket, mixing and packaging for delivery.
Note on your map where the soil samples were taken for comparison against future pH tests.
Deliver samples to the testing facility according to the instructions you've received.
Things You Will Need
- Soil sample cartons, one for each sampling area
- Paper and pencil
- Sampling tube (hollow soil probe)
- Buckets, one for each sampling area
- Hand shovel or trowel
- Soil sample tubes, also called probes, are sometimes available as loans from your county extension agent. They are also available for purchase at some places where growing supplies are sold. Call around.
- Allow two to three weeks for results.
- The soil test that reveals pH will also give you other information like its nutrient and salt content and soil texture.
- Test lawns before planting and then every two to three years.
- Though their are home pH testing kits available, they are not as reliable as tests done by a lab. Some home kits, the Arizona Master Gardener Manual warns, are very poor with their cost no indication as to their accuracy. Since you might want to amend your soil based on this test, which can become expensive, it is better to rely on a lab.