Areas with different slope, color, drainage, texture, or management history should be sampled separately. Each sample to be tested should be a thorough mix of 10-15 cores taken randomly or in a scientifically determined pattern. Remove a shovelful of soil to the depth you wish to sample, then cut a one-inch section from the wall of the hole you have just dug. Place it in your mixing bucket. Care should be taken that an equal amount of soil is taken at each of the sampling sites, so that the resulting composite sample will represent all the sample sites equally.
Clean tools are essential for sampling soils.
If specialized analyses are to be done, avoid brass, bronze, or galvanized tools, which may contaminate your samples with copper and zinc. Clean probes or shovels made of stainless steel are preferred. A small amount of lime or fertilizer residue left in the bucket can severely distort your results. Collect soil samples two to three months before planting. In so doing, you will get your test results in plenty of time to plan your soil amendment and fertilization.