Know your soil for healthy plants
Published: Monday, November 1, 2010 at 11:36 a.m.
Last Modified: Monday, November 1, 2010 at 11:36 a.m.
Your plants need 16 very specific nutrients in the right proportions for healthy growth. Nitrogen, phosphorous and potassium are considered major or primary elements, and are required regularly in relatively large amounts; however, calcium, sulfur and magnesium are secondary nutrients and are required in more moderate amounts. All of the other 12 are required in much smaller amounts, but are just as important as the major nutrients. If any of the 16 essential elements are not present in proper amounts, plant growth and health will decline. On the same token, if some of the same nutrients are present at excessive levels, they can be toxic to plants and also become a source of pollution in the environment.
To determine the needs of your specific crop, including home lawns and gardens, you need to take regular soil samples. In North Carolina, these samples can still be analyzed at no charge by the NC Department of Agriculture and Consumer Services. In order to get this free analysis, you must pick up soil sample boxes from your local Cooperative Extension offices or from a garden center that keeps them on hand for their customers. Once you have the boxes (kits) you will need to follow the steps below to collect and send in your samples. The Cooperative Extension no longer mails these samples to the lab, so you will need to do this yourself.
1. Collect 12 to 15 small samples, from within the top six inches (four inches for lawns) of the soil, within each crop area. It is important to take these samples from various locations as possible. An example of the sample would be from a 2 inch diameter and 6 inches deep. The more small samples collected will give a better, more uniform representation of the area. A stainless steel soil probe is the ideal tool, but a bulb planter or spade will work. Just make sure that they are not rusty or have a galvanized coating.
2. As samples are collected, mix them together thoroughly in a plastic bucket, or heavy paper bag. Galvanized, copper or tin buckets can contaminate the soil and give inaccurate test results.
3. Remove all debris, organic matter and rocks. Transfer about a cup of soil from the sampling container to the soil sample boxes provided by the NCDA. If this soil is wet allow to dry before placing into the sample boxes as the moisture will compromise the integrity of the box.
4. Print a number or code on each box that will correspond with the areas sampled, along with your name and address on each box. This information will be also printed on a sampling form that will be sent along with the samples. Remember you should keep a copy of this information in your files to allow you to use the results when they are sent to you. Once tested, the sample results will be sent to you by e-mail. NCDA&CS will no longer mail you the results.
Currently, turnaround time between sending samples in and getting the results posted to the internet is about 1 week. If you wait to send samples in until spring the turnaround time will increase to two months or more.
Should you need assistance reading the results after receiving them, feel free to contact your local Cooperative Extension office. The Henderson County Extension Office can be reached at 828-694-4891 or by visiting henderson.ces.ncsu.edu.
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