ARCHIVE: Fertiliser Manual (RB209)

Root Vegetables

 

SNS, P, K or Mg Index

 
 

0

1

2

3

4

5

 

 

kg/ha

 
Beetroot 

Nitrogen (N) - all soil types

290

260

240

220

190

120

60

Phosphate (P2O5)

200

150

100

50

0

0

0

Potash (K2O)

300

250

200 (2-)
150 (2+)

60

0

0

0

Swedes

Nitrogen (N) - all soil types

135

100

70

30

0a

0a

0a

Phosphate (P2O5)

200

150

100

50

0

0

0

Potash (K2O)

300

250

200 (2-)
150 (2+)

60

0

0

0

Turnips, Parsnips     

Nitrogen (N) - all soil types

170

130

100

70

20

0a

0a

Phosphate (P2O5)

200

150

100

50

0

0

0

Potash (K2O)

300

250

200 (2-)
150 (2+)

0

0

0

0

Carrots

Nitrogen (N) - all soil types

100

70

40

0a

0a

0a

0a

Phosphate (P2O5)

200

150

100

50

0

0

0

Potash (K2O)

275

225

175 (2-)
125 (2+)

35

0

0

0

All Crops 
Magnesium (MgO)

150

100

0

0

0

0

0

a. A small amount of nitrogen may be needed if soil nitrogen levels are low in the 0-30 cm of soil (see ‘Fertiliser use for vegetables’ above).

Nitrogen – all crops

Apply no more than 100 kg N/ha in the seedbed. The remainder should be applied as a topdressing when the crop is fully established.

Phosphate and potash – all crops

High yielding root crops can take up large amounts of phosphate and potash. The amounts removed can be calculated from the known yield and the amount of phosphate and potash per tonne fresh produce shown in Appendix 5. It is important to do this to maintain the target Index for both phosphate and potash. Where straw is used to protect carrots and is subsequently incorporated into the soil, it contributes approximately 1 and 8 kg phosphate and potash, respectively, per tonne of straw (see Appendix 5). These amounts should be considered
when calculating the phosphate and potash requirements of following crops.

Carrots – sodium

On sandy soils apply 200 kg Na2O/ha as salt and deeply cultivate the application into the soil before drilling.

Don’t forget to:

  • make allowance for nutrients applied in organic manures (see Section 2)
  • ensure the phosphate and potash offtake is balanced by application on Index 2 soils and check that the soil is maintained at Index 2 by soil sampling every 3 – 5 years
ADLib logo Content provided by the Agricultural Document Library
© University of Hertfordshire, 2011