|
SOIL NUTRIENT |
NEEDED BY: |
REQUIREMENTS |
|
Nitrogen (N) |
All
plants, especially leafy vegetables and grasses |
For
leaf and stem growth. Soon washed out of the soil by rain,
especially on sandy soils. Replenish every year. |
Phosphorus (P)
(as phosphate) |
Root
crops and all young plants; also flowering, fruiting, and
seeding plants |
For
root growth and the production of flowers and seeds. Remains
fixed in the soil for 2 or 3 years after application; less so in
sandy soils. |
Potassium (K)
(as potash) |
Flowering and fruiting plants |
For
flower and fruit formation, maintaining general growth and
providing resistance to disease. Remains in the soil for 2 or 3
years after application; less so in sandy soil. |
|
Calcium (Ca) |
All
plants |
For
general plant growth; encourages the growth of soil bacteria
that are responsible for producing certain plant foods.
Deficient in acid and potassium-rich soils. |
|
Magnesium (Mg) |
All
plants, especially tomatoes and roses |
For
the production of the green pigment chlorophyll. Deficient in
well drained or potassium-rich soils. |
|
Trace elements: Iron (Fe), Boron (B), Cobalt (Co), Copper (Cu),
Sulfur (S), Manganese (Mn), Zinc (Zn), Molybdenum (Mo) |
All
plants |
For
general plant growth. Rarely dificient in well-tended soils.
Certain plants have higher demands for trace elements, which can
be supplied by specially formulated fertilizers, such as
rhododendron feed that has added iron and manganese. Sulfur is
more likely to be deficient in rural areas than in urban ones.
Soil type may affect the availability of certain elements - the
calcium in lime may render iron and maganese unusable by plants,
for instance. |
