Soil Test, Anyone?

By Paul James

When is the last time you had your soil tested? Or perhaps more to the point, have you ever had your soil tested? Chances are the answer to the first question is “Can’t remember,” and the answer to the second is “No.” And that’s too bad, because a soil test can reveal problems you never knew you had and make a huge difference in how well your plants grow.

Thankfully, getting a soil test is a pretty simple and inexpensive procedure, and you don’t have to study for it. What’s more, it’s not something you need to do every year. Actually, I’d suggest you consider testing only every three to five years or so, because changes in soil chemistry generally don’t occur very rapidly.

A basic soil test performed by folks at OSU’s Soil Science Lab will reveal four things about your soil: its nitrogen, phosphorous, and potassium (or NPK) levels, and its pH. That’ll cost you $10. You can pay more to get more, including such things as secondary and micronutrient levels, and well as organic matter content, but those tests aren’t all that necessary for homeowners.

To prepare a soil sample, you’ll need a clean trowel, a bucket, and a one-quart zip-lock plastic bag. Use the trowel to dig up the soil to a depth of roughly six inches, and collect at least a dozen or so two- or three-tablespoon samples from several locations in your lawn, flower bed, or veggie garden. (Consider each location as a separate test.) Drop the samples in the bucket as you go, then mix the soil well and remove any sticks or other debris.

Fill the plastic bag with the mixed soil, and take the sample to the OSU Extension office at 4116 East 15th Street. Within two or three weeks, you’ll receive the test results along with recommendations on the nutrients you need to add and how much. You might even learn that you should stop adding certain nutrients.

Fair warning: Interpreting the test results can be a bit confusing, but don’t let that discourage you. Just bring the information to our Solution Center, and let Jennifer or Taylor give you step by step instructions on how to make the necessary adjustments to your soil’s NPK and pH levels so that your plants will be healthy and happy all season long.