Soil Samples

Karen Cambre, Sharpe, Kenneth W.

News article for January 14, 2019

With the start of a new year, make it your resolution to take soil samples where you are going to make new plantings or where you are having problems. It is impossible to look at the soil and tell what it needs.

Each year I talk with hundreds of people who have problems growing everything from their lawn grasses, flowers, vegetable gardens, shrubs, trees, pastures and wildlife food plots. I ask some diagnostic questions to help me determine their problem and get them going on the right track, but many times the information I need to help is missing.

It is very important to know if the nutritional needs of the plants are being met. This means more than applying fertilizers; it also takes into account the condition of the soil.

Soil samples will tell us first if you have soil pH problems. If pH is the problem then fertilizer is not going to cure your problem.We will have to either lower the pH with sulfur or raise it with lime to accommodate the crop you are trying to grow.

Liming is a common practice here because our native soils are acid. Lime would correct low pH, supply calcium and magnesium, promote bacterial activity in the soil, increase the availability of phosphorous and reduce the availability of toxic elements that can reduce growth and yield in some plants. The unanswered question would be how much do I need? The soil lab will react your soil with lime and calculate a rate for your soil and crop.

If you have had tomato problems where the bottom of the tomato turns black just about the time it gets ripe, that is call blossom-end rot and it is common. That sounds like a disease but it is really a calcium availability problem that can be corrected or prevented by using a simple soil sample.

In addition to pH you will also get an analysis of how much phosphorous, potassium, magnesium, calcium, sulfur, copper and zinc are in the soil. You will also get a recommendation on how to correct any problems and how to fertilize based on what you intend to plant.

To take a soil sample get a small shovel and a bucket. Use the tip of the shovel and go down 2-4 inches into the soil and put that soil in the bucket. Within the area that you want to sample randomly select 10 -20 places to pull soil and place all those subsamples in one bucket. Now mix the subsamples together with your hand and pull out 1 pint of the mixture to be sent in for analysis.

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Place the pint of soil in any clean container such as a plastic bag or jar and bring it to my office to be submitted to the lab. The cost is $10 per sample and you will receive the results usually within 10 working days.

There is a temptation to pull the soil from just one spot and send that in, resist that temptation. The soil sample is nothing more than an average of the soil in an area and the more subsamples you take to make the sample, the better information we get back.

You may have noticed that you usually get sick with flu or other aliments when you are more stressed, run down and not eating properly. Plants are the same; if you can keep them actively growing they are less susceptible and more resistant to diseases and insect damage.

Spring vegetable gardening season will be here before you know it. Gardening projects require a lot of energy and financial resources. It only makes sense to do everything possible to make the project successful. Resolve to get a soil test and then do it!

For more information on these or related topics contact Kenny at 225-686-3020 or visit our website at

1/11/2019 4:31:45 PM
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