Ship to the lab for analysis as quickly as possible. Request a complete analysis early and late season. In between, nitrate and phosphate analysis may be sufficient to chart a plants progress. Two samples are always needed to know the tend in a nutrients availability. Interpreting the Results Sufficiency levels of nutrient change over the season, so it is important to evaluate the lab results based on crop stage.
Varieties vary greatly in sufficiency levels as well.
Below are tables to interpret petiole analysis results. Phosphates Phosphate sufficiency levels are the same for all varieties more or less and it is a straight line down in levels across the season. The table below summarizes the desirable levels. After Planting 1000 Micronutrients Again desirable petiole levels don't vary much from variety to variety, but the vary across the growing season. Use the tables below to interpret your petiole lab results.