UMASS Soil Testing


Mail-order analysis

If you take gardening seriously, then you know it all starts with soil health. But you can’t just look down and analyze it. The University of Massachusetts at Amherst offers cheap soil tests that will provide you with a comprehensive rundown of what your soil contains and what it needs.

I first had the soil test done back in 2001, and it showed low phosphorous, and very low levels of heavy metals. It gave specific instructions for adding nitrogen, phosphorous and limestone. For $9 they perform a standard soil test resulting in the following information: pH level, buffer pH, extractable nutrients (P, K, Ca, Mg, Fe, Mn, Zn, Cu, B), extractable heavy metals (Pb, Cd, Ni, Cr), and extractable aluminum, cation exchange capacity, percent base saturation. For $13 you get everything in the standard soil test and the amount of organic matter in your soil.

One of the most vital tests is the extractable heavy metals. Anyone planning to grow food near an old house that may have been painted with lead-based paints should perform this test to make sure you’re not growing your organic veggies in poisoned soil, which pretty much defeats the purpose.

The soil test also provides specific fertilization recommendations, based on what you’re growing. This helps you customize your fertilizing practices, by letting you know what you need to add to make your soils more fertile. More importantly, you can use that soil test to cut back on the stuff your soil doesn’t need.

These are some of the cheapest soil tests available anywhere, and they provide immensely useful information. I first heard about them during my Master Gardener training a couple of decades ago. My only caveat is that the test is only as good as the sample provided. Make sure you follow their directions carefully.

I’m planning to redo the soil test, since I had raised beds added recently. The raised beds were filled with topsoil from a local company that composts yard and food waste. Now that I have good raised beds and drip irrigation, I’m gardening on a much larger scale and need better information. I took half a dozen large plastic sacks full of lettuce and spinach to the local food bank last year, and am hoping I’ll be able to do that again next year.

-- Amy Thompson 09/17/09