Using the correct tools when taking soil samples can have a significant impact on the accuracy of the results. Photo:calag.ucanr.edu.
Improve your soil quality with effective sampling by Jaco Cilliers
T
obacco farmers in Zimbabwe are preparing for the coming planting season. Part of this process is raising the seedlings that will be transplanted onto the fields later in the year. To ensure the best possible outcome, the conditions in which the seedlings are planted need to be perfect. This includes having healthy soil that contains sufficient nutrients and has the correct pH level. Tobacco is sensitive to acidic soils, and the pH balance in the soil can make the difference between a good or bad harvest. It is therefore very important to know what the pH level and the chemical composition of the soil is. These principles of soil sampling also hold true for the production of other crops. There are options when it comes
to soil sampling. The most effortless, and also the most expensive one, is to have professionals come and take samples from your soil, and then test and analyse them in a laboratory. The more cost-effective way is to take the samples yourself and send it to a laboratory for tests and analysis. When taking your own soil samples, there are a number of factors to consider that can impact on the accuracy of the tests. These include: • When to take samples • Where to take the samples • Tools used • Depth of sampling • Frequency • Correct handling of samples The time of year that you take the soil samples is crucial to success. Samples
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should be taken just before you plan to use that particular piece of land. Keep in mind that you also cannot wait too long, because you need enough time to apply corrective measures if needed. It is also best to collect samples from fields before any soil treatment is performed. Collecting samples after fertilisers or compost have been added may lead to inaccurate sampling. Also avoid sampling in areas where there is too much water. Soil should be moist, but not muddy, for the most accurate samples. As with any other job, sampling is a lot easier with the right tools. It is recommended to use proper coring equipment because it allows the samples to clearly separate the different layers. This will enable you to get accurate results for each layer. Using 39
