Sulphate of Potash
and Avocado Production
(150-200 ppm) in the soil before planting,
Mineral nutrition while maintaining a balance with calcium and
The avocado is a tropical to subtropical tree, Ideally, potassium should represent between
with severe cold being the most limiting factor 0.7 and 2.4 % of the leaf dry matter. In a potassium
to its successful cultivation. It can be grown on deficient tree, the leaves are small and narrow
a wide range of soil types, but requires good and necrotic spots appear on the older leaves.
drainage as it cannot tolerate flooding. A soil A high level of potassium in the soil and leaves
pH from 6 to 6.5 is preferable. reduces the development of both vascular
browning and pulpy spots in the fruit.
Mineral requirements for different avocado
cultivars (kg/ton of production)
N P2O5 K2O
Hass 3.60 0.55 6.10
Fuerte 1.30 0.39 2.35
Lula 2.80 0.80 5.46
In the past, the avocado was thought to need
few mineral nutrients. Deficient trees may not
show the symptoms immediately, so mineral
nutrition should be monitored through regular
leaf and soil analysis.
Potassium deficiency in avocado leaves
for higher yield
The avocado tree does not tolerate high levels
of chloride, either in the soil or in irrigation
water, with a toxicity threshold considered to
be 0.25% chloride in the leaf dry matter.
Consequently, chloride-based fertilizers such
as MOP (potassium chloride) should be avoided.
The main symptom of chloride toxicity is a
Potassium, the key nutrient light grey-brown scorch on the tips and edges
of the older leaves, which spreads back along
them in an irregular pattern.
Potassium is an important factor for a high
level of avocado production. Its role in sugar Opposite is an example of a fertilization programme
synthesis and translocation of assimilates is based on potassium sulphate (SOP), single super
essential for the quality of the fruit. Potassium phosphate (SSP) and calcium nitrate (CaN).
should be adjusted to an adequate level Calcium is an important element to increase
the resistance of the roots to disease and the
storage life of the avocado fruit.
Canopy CaN SSP SOP
2 50 200 50
4 175 300 200
6 350 400 400
8 650 600 750
10 1000 1000 900
12 1500 1200 1600
Sulphur in avocado
The experiment below compares different
methods of applying 200kg K2O/ha to Hass
Sulphur (S) is an important nutrient for plant
avocados grown in the state of Michoacan in
growth, playing a key role in amino acid
Mexico. These are fertigation and soil application
synthesis. However, sulphur deficiency is
with and without foliar sprays after flowering.
becoming increasingly frequent.
Cumulated 2004-2006 production according The optimum range for the sulphur content in
to application method the avocado leaf dry matter is between 0.2 to
0.6%. Potassium sulphate also contains 18%
S which covers the plant's sulphur requirements.
In addition, sulphur is helpful in pest and
Source : inifap Mexique (2006)
Results show the benefit of foliar application in
enhancing root absorption and, consequently,
on fruit production.
Sulphur deficiency in avocado leaves
Thanks to the effect of its combination of
potassium and sulphur, sulphate of potash is
recommended for high avocado yields, as well
as high quality fruit.
Different forms of SOP available
from Tessenderlo Group
Standard: for direct application or for use in the
manufacture of compound fertilizers.
GranuPotasse®: a granular form ideal for bulk blending or for
direct application with an even distribution
on the soil.
SoluPotasse®: a highly soluble form for fertigation or
Imported and distributed by:
Tessenderlo Group Fertilizers
giving nature a helping hand
B-1050 Brussels, Belgium
Tel: +32 2 639 1811 Fax: +32 2 639 1940