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How to Test Soil Fertility

growing araucaria in soil image by joanna wnuk from

If you want a healthy, thriving garden or flowerbed, or if you’d like to landscape your entire property, a soil fertility test is a good place to start your planting project. Knowing the fertility of your soil, the properties the soil possesses and the essential nutrients that the soil lacks, can help you determine which minerals and fertilizers you need to add to the soil to get it to its most fertile.

Home Testing

Purchase a home soil testing kit. These kits come with the necessary tools to test and read your soil’s fertility. Organic Gardening recommends the Solvita Soil Life Test Kit, but you can also buy kits from other manufacturers, such as Vigoro and Rapitest (see Resources).

Take a soil sample. A home testing kit will provide some instruction on how to collect a proper sample. In general though, dig up several samples from the area you want tested with a spade, getting thin slices of land that reach at least 3 inches down for lawn and 6 inches down for garden areas.

Add all of the samples taken from the area of the yard to a container and mix them together until they break up and combine. Remove any large rocks or other non-soil particles from the soil.

Scoop up part of the mixed sample soil in the cup provided with the soil testing kit. The instructions that come with each specific kit provides guidance on how much soil you need to collect for each sample.

Insert the testing strip or indicator that came with the testing kit into the cup and allow the strip or indicator to sit in the cup for the amount of time indicated in the kit instructions. Normally, a soil testing kit requires a 24-hour time frame to show a result.

Get the reading from the strip or indicator. Consult the instructions that came with the kit, which usually provides direction on steps that you need to take to correct your soil if the test discovers fertility issues.

Lab Testing

Order a testing kit from a lab in your area. Most lab testing takes place at university labs. Virginia Tech, Penn State and Rutgers, for instance, all provide soil testing through their labs (see Resources).

Take several sample slices of the soil from around the area you would like to test. As with a home testing kit, take samples from at least 3 inches below the surface for lawn and 6 inches down for garden.

Put the soil samples in a container and break up the soil samples so that they can be mixed together. Remove rocks, sticks and debris from the soil and spoon 1 to 2 cups of the sample into the cup or collection bag provided with the testing kit. If no containers were provided with the kit, place the sample in a plastic baggie with an airtight seal.

Send the sample, along with any required forms that came with the testing kit, to the testing lab. The address to send the form to usually appears on the form or in the kit’s instructions.

Wait for the testing report from the lab. The report tells you the testing results and also includes information on what needs to be added to your soil to increase the fertility.

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