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Application rates - recommendations

To increase soil P Index

Use normal recommendations for Index 2 plus 700 kg Cropkare/ha until soil Index reaches 2. Check soil Indices by regular soil sampling every 3-5 years.

To meet annual crop requirements

Annual requirements for phosphate and potash depend on the crop grown and soil Indices. Recommendations for different Indices are given in Defra RB209 and are summarised in Tables A and B.

Many soils have different Indices for phosphate and potash. Where one Index is lower than the target for crop growth (2 for P, 2- for K), apply Cropkare to meet requirement at the lowest Index. Check Indices by soil sampling every 3-5 years (typically, cost of soil analysis is around 20p/ha/year).

The table below shows typical recommendations for Cropkare use in different crops. For more detail, or to refine use in a particular situation, refer to the RB209 recommendations summarised in Tables A and B.

Click the text below to view the table.

Typical recommendations for Cropkare
  Cropkare
kg/ha
Supplying
kg P2O5/ha kg K2O/ha
Winter wheat/barley
Straw incorporated
Index 0 or 1 800 96 96
Index 2 450 54 54
Straw removed
Index 0 or 1 875 105 105
Index 2 700 84 84
Spring barley
Straw incorporated
Index 0 or 1 750 90 90
Index 2 350 42 42
Straw removed
Index 0 or 1 850 101 102
Index 2 600 72 72
Winter oilseed rape
Index 0 or 1 750 90 90
Index 2 400 48 48
Peas/beans
Index 0 or 1 650 78 78
Index 2 300 36 36
Sugar beet
Index 0 or 1 875 105 105
Index 2 650 78 78
Forage rape, stubble turnips
Index 0 or 1 700 84 84
Index 2 650 78 78
Fodder beet, mangels
Index 0 or 1 1000 120 120
Index 2 900 108 108
Grass
Establishment
Index 0 or 1 800 96 96
Index 2 400 48 48
Grazing (whole year)
Index 0 or 1 400 48 48
Index 2 250 30 30
First cut silage (spring)
Index 0 or 1 600 72 72
Index 2 350 42 42
Table A. P2O5 recommendations for typical yields
  Soil Index
0 1 2 3 4
kg P2O5/ha
Winter wheat/barley
(straw incorporated)
110 85 60 20 0
Spring wheat/barley, and oats (straw incorporated) 95 70 45 0 0
Winter wheat/barley
(straw removed)
120 95 70 20 0
Spring wheat/barley, and oats (straw removed) 105 80 55 0 0
Winter oilseed rape 100 75 50 0 0
Spring oilseed rape, linseed 80 55 30 0 0
Peas and beans 85 60 35 0 0
Potatoes 270 230 180 130 50
Sugar beet 100 75 50 0 0
 
Forage maize 110 85 60 20 0
Forage swedes/turnips 100 80 60 40 0-40
Forage rape, stubble turnips 100 90 80 60 40
Fodder beet, mangels 130 120 110 90 60
Kale 130 120 110 90 60
Forage rye/triticale 80 60 40 20 0
 
Grass establishment 120 80 50 30 0
Grazed grass 60 40 20 0 0
First cut silage 90 65 40 20 0
Second cut silage 25 25 25 0 0
Table B. K2O recommendations for typical yields
  Soil Index
0 1 2- 2+ 3 4
kg K2O/ha
Winter wheat/barley
(straw incorporated)
95 70 45 20 0 0
Spring wheat/barley, and oats
(straw incorporated)
85 60 35 20 0 0
Winter wheat/barley
(straw removed)
145 120 95 70 25 0
Spring wheat/barley
(straw removed)
130 105 80 55 20 0
Oats (straw removed) 155 130 105 80 35 0
Winter oilseed rape 90 65 40 20 0 0
Spring oilseed rape, linseed 75 50 25 0 0 0
Peas and beans 90 65 40 20 0 0
Maincrop potatoes 350 325 300 275 150 0
Early/seed potatoes 220 195 170 145 50 0
Sugar beet 150 125 100 75 0 0
 
Forage maize 230 205 180 155 110 0
Forage swedes/turnips 200 175 150 125 80 0
Forage rape, stubble turnips 100 75 50 25 0 0
Fodder beet, mangels 160 135 110 85 40 0
Kale 250 225 200 175 130 0
Forage rye/triticale 170 145 120 95 50 0
 
Grass establishment 120 80 50 50 30 0
Grazed grass 60 30 0 0 0 0
First cut silage* 60/80 30/80 0/90 0/60 0 0
Second cut silage 120 100 90 60 40 0
Comparison of Cropkare recommendation and crop removal of phosphate and potash at typical yields
  kg/ha
Cropkare Applied Removal
  P2O5 K2O P2O5 K2O
Winter wheat/barley
(straw incorporated)
450 54 54 60 45
Spring wheat/barley, and oats
(straw incorporated)
350 42 42 45 35
Winter wheat/barley
(straw removed)
700 84 84 70 95
Spring wheat/barley, and oats
(straw removed)
600 72 72 55 80
Winter oilseed rape 400 48 48 50 40
Spring oilseed rape, linseed       30 25
Peas and beans 300 36 36 35 40
Potatoes       180 300
Sugar beet 650 78 78 50 100
 
Forage maize       60 180
Forage swedes/turnips       60 150
Forage rape, stubble turnips 650 78 78 80 50
Fodder beet, mangels 900 108 108 110 110
Kale       110 200
Forage rye/triticale       40 120
 
Grass establishment 400 48 48 50 50
Grazed grass 250 30 30 20 0
First cut silage 350 42 42 40 0/90
Second cut silage       25 90