Rather than collecting a single sample, numerous soils samples are usually collected from around the entire planting area, and are then composite into one sample for analysis. This allows you to minimize the total cost of analysis. A good composite is made up of 15 to 20 discrete soil sample cores from around the planting area, collecting the samples from about 6-8 inches deep with a core sampler. Mix all the soil cores together in a large bucket. After thorough mixing, fill a quart size zip lock bag with the composite sample. Label the bag for proper identification and deliver to the laboratory for analysis.
For large land area, divide your land into smaller quadrants, and then collect composite samples from each quadrant. Individual samples can also be taken, using the same technique but omitting the composite mixing. Simply place the sample directly into the quart size zip lock and deliver to the laboratory.
The sampling of plant tissue is extremely dependent on the type and maturity of the plant, as well as on the season, location, and many other factors. Please contact us for complete information on your specific crop. Detailed sampling instructions specific to the crops common to Northern California will be included here soon!