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to regular and split application by the farmers. Among the secondary nutrients, calcium and
magnesium are most critical throughout the state, which recorded about 40 and 74% deficiency,
respectively. Suphur deficiency is only to the tune of 15% in the state. The most critical
micronutrient limiting the yield is boron with more than 60% deficiency, noticed in all the crops.
On the other hand, iron and manganese toxicity are noticed in low land paddies. The general
fertility management practices include lime application to ameliorate acidity followed by
addition of organic matter. Good quality dolomite is preferred over lime since it can correct the
deficiency of magnesium also.

Crops and cropping systems

Kerala, the “land of spices and plantations” accounts for about 97% of pepper production and for
85% of the area under natural rubber in the country. In addition,coconut, tea, coffee, cashew
and spices including cardamom, vanilla, cinnamon, and nutmeg comprise the major crop
cafeteria of the state. Rice is the most important food crop grown in Kerala. It occupies 7.46% of
the total cropped area of the state. Nevertheless, home gardens comprise a significant portion of
the agricultural sector. Rice is the sole crop and coconut and seasonal crops like vegetables is
grown on the earthen bunds constructed for protecting the paddy from nearby water bodies (soils
are located below MSL) in several places.

Fertilizer consumption

Total consumption of N, P 2O 5 and K 2O were 78,580, 43,192 and 58,644 tonnes, respectively,
and consumption of ZnSO 4 was 35 tonnes in 2016-17. Urea, Factomphos (ammonium phosphate
sulphate), rock phosphate, bone meal, and muriate of potash are the commonly used fertilizers in
the state with more or less steady rate of consumption. Soluble fertilizers, like 19:19:19, MAP,
calcium nitrate are used for fertigation. Different sources of lime like calcite, burnt lime,
dolomite, etc are used both as amendments, and source of calcium and or magnesium.
Magnesium sulphate is used as the major magnesium source. Borax is widely used to correct
boron deficiency. Soluble forms of boron and ready to use formulations of micronutrient
mixtures are also commercially available for foliar application.