Leaf Analysis

Suggested Ranges for Avocado


Leaves are sampled once a year in the fall... usually mid September. Collect 20 leaves per tree (5 per quadrant). Leaves must be recently expanded, fully-mature leaves of aprox. the same size taken from the following branches:

non-flushing
non-fruiting
below 6 feet

You should call the lab doing the analysis prior to shipping the samples to determine how they prefer to have the samples prepared and shipped.

Below are the suggested ranges for nutrients based on the results of leaf analysis:
Nutrient
Suggested Range
N%
1.6 - 2.0*
P%
0.10 - 0.25
K%
0.75 - 2.0
Ca%
1.0 - 3.0
Mg%
0.25 - 0.80
S%
0.20 - 0.60
Cl%
>0.25
Na%
>0.25
B ppm
50 - 100
Zn ppm
30 - 150
Mn ppm
30 - 500
Fe ppm
50 - 200
Cu ppm
5 - 15
*  The work of Embleton, Jones and Arpaia indicate that the N tissue value for Hass should be slightly higher than Fuerte. The Leaf N for Fuerte is 1.6 to 2%. Above this value there is a yield decline. The Hass value is set at a minimum of 2 with the upper range not yet established (but probably something like 2.3%).

Dr. Ben Faber
Cooperative Extension
Ventura County

Source:
Abstract from updated Leaflet 2024, Division of Agricultural Sciences, University of California. 5/78.