Benefits of Fall Soil Sampling

Photo from www.ipm.iastate.edu

As the crops leave the fields, your grass begins to slow down and gardens are put to rest, it is time to think about soil sampling.  I am a firm believer that one of the most important tools you can own is a soil probe.  Knowing your soil’s fertility levels and pH is key to having healthy and productive land.  It also has a huge impact on managing your inputs to help maximize outputs.

Fall soil sampling allows you ample time to implement research-based fertility recommendations before spring planting.  When you receive the soil test results, read the pH and lime recommendations.  You may need to apply lime to neutralize soil acidity.  To be fully effective, agricultural lime should be applied in the fall because it takes about six months to break down and react with the soil.  So, the earlier you spread lime, the better.

The turn-around time for samples is much faster in the fall, usually within a few days, because fewer people are submitting samples this time of year.

All recommended fertilizers, except nitrogen, can be applied this fall.  Buying fertilizer in the fall usually will save you money because prices are cheaper due to lower demand.  Also, we usually have drier soil in the fall making it easier to get the spreader truck into the field.

Farmers who don’t test fields and pastures can only guess at fertility needs.  Estimating how much fertilizer is needed often results in applying more than necessary. And this is an unnecessary expense, not to mention the negative environmental effect.

The McLean Cooperative Extension Service has soil sample bags, details on taking accurate samples and other pertinent information.  Soil samples analysis cost $7.

Your soil analysis report is based on that little pint of soil you submitted. So for the most accurate report, take the best soil samples possible.

You’ll need to take different samples for various land uses such as agricultural fields, lawn, garden, fruit trees, ornamental shrubs and azaleas because these may have distinct fertility and acidity or alkalinity requirements.

Take a sample from poor growing area and from adjacent areas of good growth. Mark each sample with a letter, or numbers on a field map.  Collect at least 10 soil cores for small areas and up to 20 cores for larger fields.

 How deeply you take cores for farm use depends on the tillage system used. For tilled areas, take cores from the surface to plow depth, usually six to eight inches.  Take cores down to a four-inch depth in no-till fields and pastures. For home lawns, take cores from the surface down to four inches. For gardens, ornamentals and fruit trees, take cores down to six to eight inches.  Be sure to take all cores from an area at the same depth.

After you’ve collected soil cores, put them in a clean, dry plastic bucket, crush the soil and thoroughly mix it.  Allow this to air dry in an open, contamination-free space.
When it dries, fill the sample bag and completely fill out the information sheet. A separate sheet is needed for agricultural soil, home gardens, lawns and turf grasses and commercial horticultural crops.

It’s a good idea to take core samples around the same time each year to compare results from year to year.

For more information about soil sampling, contact the McLean County Cooperative Extension Office at (270)273-3690.  Educational programs of the Kentucky Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability or national origin.