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To get the best results in your garden or landscape, have a soil sample tested. The results come with recommendations based on the type of plants you intend to grow.


Spring is not far away, and we gardeners are checking out spring catalogs, imagining what our gardens will look like in May.

Would you like healthier flowers or a more productive vegetable garden? Soil sampling is one of the best things you can do. By analyzing your soil, the LSU Soil Testing Lab can find problems and recommend treatments to improve your results. Pre-addressed soil sample boxes are free to pick up at your parish extension office and most garden centers.

While sampling is quick and easy, doing it correctly is important. There are several good YouTube videos that describe the procedure, and each sample kit has instructions included.

Get a separate sample for each area of your landscape — lawn, vegetable garden, perennial bed, citrus tree area. Each sample should be made up of at least 10 subsamples. 

To take a subsample, dig a hole at least 6 inches deep with a spade or trowel. Now, slice off a vertical edge of the hole about one inch thick and six inches long and place this in a clean bucket or plastic bag. Dig the remainder of your subsamples in the same manner randomly over the area. Once all subsamples are collected, thoroughly mix them and place a cupful or so in the sample bag provided with the kit. This is your soil sample.

Label the bag clearly and in a way easily identifiable to you, such as south lawn or vegetable garden.  Avoid taking subsamples from any spots that are vastly different from the majority of the area.

Place all of your clearly labeled sample bags in the pre-addressed box provided. Enclose the completed “Soil Test Kit Request Form” along with payment. Fees include $6 mailing for each box and $10 for each sample in the box for a routine test.

The form also specifies fees for any additional tests you may want done. More information can also be found at the “Soil Testing & Plant Analysis” page on the LSU Agricultural Center website.

Now seal the box and mail it. In a couple of weeks, your results will be mailed and emailed to you. Properly completing the request form is extremely important. The recommendations provided to you by the Soil Testing Lab are based on the soil test results and the intended use of the area. Recommendations for lawns, for example, are very different from those for vegetables or azaleas. Likewise, there are different recommendations for different types of vegetables. Being thorough and specific will lead to more precise recommendations that lead to better gardening results.

How often should soil samples be taken? In established lawns, orchards and perennial beds, sampling every three years should be sufficient unless plants are showing signs of a problem. For vegetable gardens and annual beds that have regular plant turnover, sampling should be done yearly or even between each crop, especially if the crops are very different.

Joe Willis and Anna Timmerman are LSU agricultural extension agents. Email questions to