Introduction

• Proper nutrition at nursery stage is important for desired growth

and berry production in grapevine.

• There are 13 mineral nutrients found essential for the growth of

grape vines.

• The macro-nutrients, needed in concentrations of more than 1000

ppm are nitrogen, phosphorus potassium, calcium, magnesium,

and sulphur.

• The micro-nutrients, needed in concentrations of less than 100

ppm are iron, manganese, zinc, copper, chlorine, boron and

molybdenum.

Nutrient and Soil pH Relation

• Availability of inorganic nutrients to plant has relation soil PH. Vis a

vis acidity or alkalinity of the soil.

• Slightly acidic soils with pH 5.5 to 6.5 are most suitable for crop

production in agriculture as all essential nutrients are readily available

in this pH range.

• In alkaline soils, some mineral ions such as iron, manganese and

copper precipitate and become unavailable to the plants.

• Aluminium toxicity occurs at pH less than 4.5, and manganese toxicity

occurs at pH less than 5.5, depending on other environmental factors.

Plant Tissue Analysis

• Plant tissue analysis is a foolproof method of analyzing the nutritional

requirements of grape vines.

• Leaf petioles or leaf blades are used for tissue analysis, as they are

sensitive indicators of nitrogen (N), phosphorus (P) and potassium (K)

status. Stalked leaves opposite to the basal bunches are harvested

randomly for analysis.

• Approximately 200 petioles are required for a sample. The petioles are

washed, surface dried and then analyzed.

• Older leaves are used to analyze mobile nutrients while growing tips of

shoots are required for immobile nutrients.

Nutrient supply through Fertilizers

• Recommendations from the manufacturers must be considered for

quantity of doses and method of application.

• Sandy soils are more prone to leaching and need fertilization more

often than loamy or clay soils.

• Light soils require frequent applications of small amounts of soluble

form of nutrient like nitrogen.

• Vine roots are concentrated under the drip irrigation supply line,

making it convenient to supply fertilizer through the drip water which

is called Fertigation.( Fertilization through Irrigation)

• Excessive application of Nitrogen (N) in grapes causes excess

vegetative growth. N fertilizers should be apply in 2-3 split doses to

avoid leaching of mineral nitrogen.

• Right choice of a nitrogen fertilizer is particularly important for drip-

irrigated nursery to avoid acidification

• Ammonium Sulphate is the most acidifying nitrogen fertilizer,

followed by urea, ammonium nitrate, di-ammonium phosphate (DAP)

and mono-ammonium phosphate (MAP).

• Calcium Ammonium Nitrate (CAN) and Potassium Nitrate fertilizers

are free from acidity causing effects.

Nitrogen

Phosphorus

• Soluble forms of Liquid and solid state phosphorus (P), such as

MAP or phosphoric acid, are applied through drip irrigation and

allow Phosphorus readily available to vines.

Potassium • Potassium (K) can be applied by broadcasting or banding the soil

surface, in a furrow, or by Fertigation with drip irrigation.

• K based fertilizers commonly used are Potassium Nitrate, Muriate

of Potash (Potassium Chloride) and Sulfate of Potash.

• High levels of Potassium can adversely affect the quality of wine

grape varieties.

Calcium and Sulphur

• Calcium and Sulphur are normally not usually applied but are

supplied indirectly through Gypsum, Lime and Super Phosphate.

• Sulphur is applied to foliage as colloidal sulphur for prevention of

powdery mildew and for mite control.

• Sulphur is also received from use of sulfate of potash, when used

to improve soil potassium levels in some soils.

Magnesium

• Magnesium fertilizers include Epsom salts (Magnesium

Sulphate) and Potassium Magnesium Sulphate.

• These fertilizers can be broadcasted or applied through drip

irrigation.

• Dolomite lime (Calcium Magnesium Carbonate) used for raising

soil pH in highly acidic soil,also contribute magnesium to the soil.

Foliar Application of Nutrients

• Nutrients required can also be applied via foliar sprays. Micro-

nutrients are commonly applied by this method.

• Boron (B) is applied in the form of borax (Solubar or Bortrac).

• Zinc (Zn) is applied in the form of Zinc Sulphate or Zinc Oxide.

• Manganese (Mn) is applied in the form of Manganese Sulphate

with Zinc sprays.

• Mancozeb fungicide will supply Mn as it breaks down, and is

absorbed by the plants.

• Copper-based fungicide sprays will break down and supply Cu to

the plants.

Nutrients through Organic Matter

• Compost is a rich source of organic matter containing almost all

the essential nutrients, can be applied in poly bags for planting

rootstocks.

• The compost should have a carbon to nitrogen ratio of less than

20:1 to reduce the risk of N draw down.

• Organic mulch is low in Nitrogen, However, it contains sufficient

amount of Calcium and Potassium that is readily available to

vines in the early growth stages.