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Notes regarding fertilisers and their uses 

SOME NOTES THAT MAY BE HELPFUL IN SELECTING FERTILISERS, ETC.

 

Manures and composts are excellent soil conditioners but are relatively low in nutrients.

 

Plants take 3 major elements from the soil for growth:

  1. nitrogen (N) for leaves
  2. phosphorus (P), for roots, and
  3. potassium (K), for fruit and flowers

 

The following chart indicates the approximate percentage of these elements in the various fertilisers.

 

Organic

                                               %N             %P             %K

Animal manure                       0.6              0.1              0.5

Garden compost                    0.5              0.3              0.8

Bone meal                              3.5              20               -

Dried blood                             21               -                  -

Fish, blood and bone              6                 6                 6

Hoof and horn                        13               -                  -

Rock potash                           5                 8                 10

Rock phosphate                     -                  26               12

Wood ash                               0.1              0.3              1

 

Inorganic

 

Growmore                              7                 7                 7

Potassium sulphate                -                  -                  49

Potato fertiliser                       12               11               18

Rose food                               5                 7                 10

Sulphate of ammonia             21               -                  -

Sulphate of potash                 -                  -                  48

Superphosphate                                        16               17

Tomato fertiliser                     5                 4                 11

Vitax Q4                                 5.3              7.5              10