Iowa soil testing: where to send a sample and how to take one

Iowa soil testing: where to send a sample and how to take one

Does Iowa State still test soil?

No. ISU Extension states that soil tests are not available from Iowa State. Its own lab is closed, and county extension offices now hand out kits for samples that get analysed somewhere else. This is the single thing most people searching for Iowa soil testing have wrong.

What does a soil test cost?

It depends entirely on the lab and the add-ons, and each lab publishes its price on its own submission form, which is why no figure appears on this page. Both university labs ISU points to, Minnesota and Wisconsin, list current prices with their forms. The county kit itself is free.

How much soil do they need?

One mixed sample built from 10 to 15 cores taken at 4 to 8 inches across the area, which fills a quart freezer bag comfortably. One core from one spot is the commonest mistake and it makes the report describe that spot rather than your yard.

Should I test for lead?

It is an add-on rather than part of the basic test. It is worth adding for a vegetable bed beside an older house or a busy road, where paint and fuel residue are the usual sources. The basic package covers phosphorus, potassium, pH and organic matter only.

When should I sample?

Fall or early spring. Any time the soil is unfrozen works, and sampling at roughly the same point in the year each time is what makes one report comparable with the last.

Where do these facts come from?

Iowa State University Extension's home gardener soil testing page and its Mahaska County office page, both read on 16 September 2026 and linked at the foot of this page. Lab prices and addresses change, so take those from the lab's own form.