Leaf analyses are often performed when there is a deficiency or excess symptom. On the other hand the elements in the leaf tell us something about the nutrient condition of the soil. The nutrient ratio in the leaves differs per plant cultivar and per location. Therefore it is important not to interpret the target values absolute.
Deficiency and excess symptoms.
When plants show deficiency it is best to analyze good and bad plants. This way a good comparison can be made between plants of the same cultivar and grown under the same circumstances.
To examine if the plant can take up enough nutrients it can be helpful to do a leaf analysis. By building up a history of your own target values it is possible to get to know which nutrient levels in the leaf give the right leaf colour or leaf strength.
In case of crops sensitive for leaf tips a leaf analysis can be performed to see if the manganese or boron levels are not too high or too low.