This example of a fall container uses Mesa Yellow blanket flower,
burgundy and pink mums, orange marigolds, ornamental kale and a vining, cold-hardy succulent. Soil testing can help gardeners amend their soil, which tends
to be alkaline in Colorado. (Colorado State University
Extension — Courtesy Photo).

Spring is just around the corner, and enthusiastic gardeners are already plotting to get their gardens in shape for the growing season. From soil to sunshine, it all takes planning.

Whether you’re new to gardening or have lots of experience you may wonder just how healthy your soil is — especially if the previous season wasn’t quite as successful as you’d hoped and you’re not sure why. Rather than guessing and adding products your soil may not need, consider a soil test.

Why a soil test?

There are many advantages to soil testing for home gardeners. It can be valuable to establish a baseline of your soil’s limitations such as the pH level, salt levels and possible need for fertilizers. Once you have identified a need to amend your soil, CSU Extension Fact Sheet No. 7.235 can guide you further.

A standard soil test will not tell you if you’re over- or underwatering, if you have insufficient soil drainage, compacted or diseased soil, improper sun exposure or if you’ve selected poor plant varieties for the area. Talking to a Colorado Master Gardener about your gardening woes is a great way to identify those issues.

What’s included in a standard test?

Standard test results typically include information about soil texture, percentage of organic matter, soil pH, the percentage of lime, soluble salts and nutrients (nitrogen, phosphorous, potassium and micronutrients such as copper, iron, manganese and zinc). Additional tests can be run for special needs like lead content or sodium problems.

How is soil tested?

Purchasing a simple home soil test kit is one option. Be aware that many home test kits are based on the pH (acid or alkaline) of your soil. If you decide to try a home test kit it’s important to read the label. An acid-based test may not be as accurate on the alkaline soils in Colorado. Some tests only give the range of pH, and you’ll want to know the precise pH — it can make a huge difference for the growth of some plants.

For the most precise measurements, a professional test by a lab is preferable. CSU Extension offices often offer soil test services. However, the lab at Colorado State University in Fort Collins is closed during the move to the new SPUR facility in Denver. To learn more about the SPUR campus and to check for updates on soil testing availability, go to

In the meantime, CSU Extension recommends Ward Laboratories in Kearney, Nebraska, for routine home garden soil testing. The test is $20, and you can find information about how to collect a sample, along with forms to fill out, at

Weld Laboratories in Greeley can do a home garden test, but is more for agricultural soil testing at three levels. A routine test is $20, essential with micronutrients is $26 and complete soil for $35. For information, go to

Healthy soil is the first step to a healthy and successful garden!

By Patty Rhodes, Colorado State University Extension. Patty Rhodes is a Colorado State University Extension Colorado Master Gardener in Boulder County. For more information on this and other topics, visit or contact your local CSU Extension Office.