Testing the soil for home landscapes doesn’t need to be done every year. They are expensive. Start with a baseline soil test (beginning) and test the soil every three to five years or when you think it is necessary. Many of these retail home soil tests can also be marketing tools for selling amendment products.
Home soil testing come in kits like La Motte’s or a soil sample you can send in for analysis like the one below. Testing raised beds for gardening is no different than a small garden area without sidewalls. Make sure ALL the important plant nutrients have been tested in desert soils.
There has been a lot of negative endorsements in general info about home soil tests. But in my opinion they aren’t too bad if you are looking for general numbers.
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| This is an example of a home soil test result from Las Vegas, Nevada. It was not too bad. Not as precise as a commercial agricultural soil testing lab but not too bad. |
Agricultural Labs
For more precision I would recommend a commercial agricultural soil testing laboratory that can invest hundreds of thousands of dollars in important equipment. For research we use A and L Soil Testing Laboratory in Modesto, California, or do it ourselves but a good soil testing labs are considerably less expensive than doing it yourself for research. The major advantage of a lab doing it for a fee and home testing is usually the numbers of tests you can run. Home testing usually involves several tests for the same price while a commercial lab you only can submit one soil sample for a fee.
Use a Local Lab
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| This is an example of a commercial agricultural soil testing laboratory report. |
Commercial agricultural soil testing laboratories invest a considerable amount of money in testing equipment. They are expensive but when accuracy is needed they do a very good job.
Examples of commercial agricultural soil testing laboratories in desert areas to consider include A and L in Modesto, and IAS in Phoenix,
In some states an agricultural soil test is available from the University. These are a good bargain and give you valuable and accurate information.
What to Test?
Most soil testing includes nitrogen, phosphorus and potassium and a few other nutrients. Besides these, in desert soils make sure your soil is tested for iron, manganese and zinc as well. Don’t forget the pH (alkalinity) and EC (salts) to include the salts of sodium, chlorides and boron. Boron is important for soil testing in desert soils.
Remember…”garbage in, garbage out.” Always submit a good soil sample.
what is the function Soil for Home Gardens?
the function of a soil for home gardens is to provide a place for the raising home vegetables and fruit trees. Our soils are desert soils, low in organics possibly high in alkalinity and salts. Adding water to this soil helps but it will not provide the increase in organics needed. Adding more organics, such as compost, to these soils helps and is usually adequate unless there is a chemical (high sodium, high chlorides, high boron) or physical problem (caliche) with the soil. The amount of organics to add to raise the organics of a soil is not a simple 1:1 addition. Adding as much as 30% compost to a soil may increase the soil organics about 8 to 10%.