Fall is the best time to take soil samples for your lawn or garden or any other part of your landscape that grows plants. Soil samples taken now come closer to representing the soil's true nutrient status as encountered by a growing crop than those taken at other times. Furthermore a soil sample taken now is very good because plants are less likely to take any further nutrients so the test provides a base line so to speak.
Try not to take samples when the soil is wet or frozen or shortly after you've applied lime or fertilizer. That's why fall and early winter is a great time to soil test. Scientists at West Virginia University, Ohio State University or even the University of Kentucky soil testing services will analyze your soil sample for available plant nutrients and soil acidity. This analysis is needed to determine the amount of lime (if any) that is needed and the proper fertilizer for the crop or plants. Soil test kits and instructions are available from your county's Extension Service office. Copies of the results are sent to you and your local extension agent, who can interpret and discuss them with you.
How often should you have your soil tested? Well, that varies, depending on the crops to be grown, previous fertilization rates and lime applications, harvested crop yields, crop sequence or other crops grown before. Land that has been converted recently into cropland or gardens should be tested each year until the proper fertility level has been reached. Generally, and I repeat generally, established lawns should be soil tested every three to five years. Test garden soil say every two to three years and perennial crops every three years.
The soil testing process is very easy to manage and the only equipment needed is a shovel and clean bucket. In most cases, when a soil sample is taken and sent in, the turn around time is two weeks to a month. Remember, soil testing is the most important 15 minutes you will ever spend in your landscape. Have a good day.