FERTILISATION GUIDELINES FOR THE TABLE GRAPE INDUSTRY

CONTENTS

1 INTRODUCTION ( Kobus Louw) _ _______________________________________________ 10 2 COLLECTION OF SOIL AND LEAF SAMPLES ( Pieter Raath) ______________________ 13 • SOIL SAMPLING __________________________________________________________ 13 – Sampling for soil preparation _________________________________________________ 13 – Sampling in existing vineyards _ _______________________________________________ 14 – Stony soil _ ____________________________________________________________ 14 – Handling of the samples _ ___________________________________________________ 15 • LEAF SAMPLING __________________________________________________________ 15 – Time of sampling _________________________________________________________ 15 – Leaf blade or petiole _ _____________________________________________________ 15 – Sampling protocol _ _______________________________________________________ 16 3 INTERPRETATION OF SOIL ANALYSIS REPORTS FOR VINEYARDS ( Pieter Raath) _ _ 19 • INTRODUCTION _ _________________________________________________________ 19 • TEXTURE _ ______________________________________________________________ 19 • SOIL ACIDITY OR ALKALINITY (pH) ___________________________________________ 20 • PLANT-AVAILABLE NUTRIENTS _______________________________________________ 20 • RESISTANCE _____________________________________________________________ 21 • PHOSPHORUS _ __________________________________________________________ 21 • POTASSIUM _ ____________________________________________________________ 23 • CALCIUM EN MAGNESIUM _ ________________________________________________ 24 • MICRO-ELEMENTS (BORON, MANGANESE, ZINC, COPPER) ________________________ 25 • BASIC CATION SATURATION RATIO (BCSR) AND SUFFICIENCY LEVEL OF AVAILABLE NUTRIENTS (SLAN) – COMPARISON OF THE CONCEPTS ___________________ 27 4 CHEMICAL CORRECTION OF SOILS DURING SOIL PREPARATION ( Dawid Saayman & Pieter Raath) _ ________________________________________________ 29 • NEGATIVE SOIL PROPERTIES ________________________________________________ 29 • CORRECTION OF SOIL ACIDITY ______________________________________________ 30 • LIMING MATERIALS _______________________________________________________ 32 • APPLICATION OF LIME _____________________________________________________ 33 • GYPSUM APPLICATIONS _ __________________________________________________ 33 • CORRECTION OF PHOSPHATE CONTENT _ ______________________________________ 34 • SUMMARY _ _____________________________________________________________ 35 5 MAINTENANCE FERTILISATION ( Pieter Raath, Kobus Conradie & Dawid Saayman ) _ ________37 • INTRODUCTION _ _________________________________________________________ 37 • NUTRIENTS REQUIRED BY GRAPEVINES _______________________________________ 38 – Quantities that are absorbed annually ____________________________________________ 38 – Distribution of elements between different organs ____________________________________ 38 – Seasonal uptake patterns ____________________________________________________ 39 • MACRO-ELEMENTS _ ______________________________________________________ 40 – Nitrogen (N) ____________________________________________________________ 40 – FERTILISATION PROGRAMME FOR NITROGEN ____________________________________ 43 – Fertilisation scheduling __________________________________________________ 43

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