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Test your soil before you build

A laboratory soil test tells you pH and nutrient levels so you can correct problems before planting. Testing early leaves time for lime or other amendments to react.

How

1. Contact a local soil laboratory or extension service and get their sampling instructions and form.
2. For each planned area (vegetable beds, orchard, lawn or pasture) take a separate composite sample. Clemson Extension advises 8 to 10 or more cores per area, mixed together.
3. Sample vegetable areas from the surface to about 15 cm (6 inches) deep using a clean trowel or probe. Avoid wet soil.
4. Send at least 2 cups (about half a litre) of mixed soil per sample.
5. Test a couple of months before planting, so any lime has time to act. Clemson suggests testing every year.
6. Compare the result with the target pH: vegetables do best in slightly acidic soil around pH 6.0 to 6.5 per Clemson. Follow the lab's amendment rates, not generic advice.
7. If the site has any history of industry, dumping, old painted buildings or fuel storage, ask the lab about testing for lead and other contaminants and consider raised beds with imported soil.

Safety: Contaminated soil can transfer lead and other metals to food and to children who play in it. If there is any doubt about past land use, test before growing food.

Do these first

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Sources

1. Soil Testing. Clemson Cooperative Extension Home and Garden Information Center, accessed 2026-11
2. Raised Bed Gardening (FS 270). Oregon State University Extension, accessed 2026-11

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