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Soil and Water Management

Soil and Water Sampling

 Have you ever applied fertilizers to your lawn?  When you went to the garden center to purchase the fertilizer, did you know what type to purchase based on the deficiencies in your soil?  If not, then it is time for you to take a soil sample!  Unfortunately, most people in Texas have never taken a soil sample.  It’s a very easy task and the information obtained from the analysis is vital in creating an environmentally safe nutrient management program for your turfgrass.  Without an analysis of your soil, you could be applying nitrates, phosphates, and other constituents into your soil that are not required.  Furthermore, you could be damaging both the turf and the environment if you use inorganic or organic fertilizers inappropriately.

As stated earlier, taking a soil sample is very easy.  Just a few simple tools are needed:  a plastic bucket, a garden spade or soil probe, and a quart size zip-loc bag.  Make sure that all of these tools are clean!  You will need to fill up the quart size zip-loc bag so that the soil testing lab has enough material to work with.  When you take the sample, do not just take one sample from one spot in your lawn.  This will not provide you with the correct analysis of your whole property.  You need to take several (minimum of 10) samples, approximately 4 inches deep, depending on the size of your property.  This does not mean that you will send in all samples separately.  The correct procedure is to place each sample into the clean plastic bucket, mix it up after you have completed the sampling process, and then take one composite quart size sample out of the bucket.  This composite sample should represent your entire lawn.  Then, send it to a reputable soil testing lab for analysis.  It will probably take about 2 weeks to receive your report.  Some people like to send in composite samples of both their front and back yards.  This is a very good idea, especially if you have a large lawn area.  It is also recommended to take separate samples of problematic areas in your turf.  It is a good way to compare the soil from the healthy turf from the stressed.  As for frequency, it is recommended to take soil samples at least every 2 to 3 years.  If you have problematic areas or you want to track your nutrient status more frequently, take soil samples on an annual basis.  The best time of year is late winter, just prior to spring green up of your lawn.  NOTE:  If you take samples during the growing season, make sure you do not take them immediately after you fertilize.  This will contaminate the sample and you will receive data that does not represent the soil in your lawn.  You will need to wait at least 4 to 6 weeks after fertilization.

 Many times, you hear folks talking about taking soil samples in order to apply the correct type and rate of fertilizer for their turfgrass.  But should we analyze our irrigation water as well?  The answer is “yes”!  Poor quality water from irrigation wells, as well as municipal water, exists throughout Texas.  Some have a high sodium content which can form sodic soils.  Water with high pH values may limit nutrient availability in soils and promote certain turf diseases.  Other waters may have toxic levels of some chemical constituents.  As a result, turfgrass quality can be compromised and additional irrigation from this type of irrigation water will only compound the problem.  A water analysis provides critical information pertaining to the types and amounts of elements found in your irrigation water.  It also provides the necessary information required to determine how well suited your water is for outdoor irrigation.  So, to put your mind at ease about your water source, take a sample!

Again, this is a very easy task!  First, you need to purchase a clean 8 to 16 ounce plastic bottle (i.e. baby bottle) with a screw-on cap.  Second, turn on the irrigation system for 5 minutes, then go to one of the irrigation heads (not a water faucet) and carefully fill the clean plastic bottle.  Finally, send it to a reputable water testing lab that tests specifically for irrigation use and your done!  It will take approximately 2 weeks to receive your report.  Use this information to determine if your irrigation water is safe to use on your lawn and whether or not you will need to make necessary adjustments to your maintenance program.  You will only need to do this once every 3 to 5 years unless you want to track problematic conditions with your irrigation water.