FAQ

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DR. EARTH® GARDENING GUIDE
30
K
S
B
O
Cl
Mn
P
Mg
Cu
H
Fe
Mo
N
Ca
Z
C
Sixteen basic nutrients are required for crop
development (plus hundreds more we know
are needed in minute amounts). Commercial
agriculture tends not to address these trace
nutrients. The oversimplied commercial
approach is like taking a multivitamin with
only an emphasis on vitamin C or calcium.
Conventional agriculture tells us that 16 basic
nutrients are all that is needed for plant growth.
It is best to use well-rounded organic
fertilizers, soil amendments, aged manures
and composts for healthy plants and soil on
a regular basis. You never know how much
of any one nutrient is needed at a certain
time of year, or time of day, for that matter.
For example, nitrogen requirements can vary
hourly depending on the time of day, soil
temperature or the amount of photosynthesis
a leaf is producing at the height of the solar
index, which is from 10 A.M. to 4 P.M.
Long-lasting organic materials are great
sources of nutrients and are a safe way to
ensure that all nutrients are available anytime
a plant needs them. We favor ocean-based
fertilizers, because they are loaded with
nutrients, well beyond the basic sixteen
needed for crop development. All the
nutrients plants use are equally important,
yet each is required in vastly dierent
amounts. These dierences have led to
the grouping of essential nutrients by the
relative quantities in which plants require
them, namely, primary or macronutrients,
secondary nutrients, and micronutrients.
Micronutrients or Trace Elements
Secondary Nutrients
Macronutrients
16 BASIC NUTRIENTS
REQUIRED FOR CROP DEVELOPMENT
DID YOU
KNOW?
NPK rating (or N-P-K) is used to label fertilizer based on the relative content of the elements
nitrogen (N), phosphorus (P), and potassium (K) that are commonly used in fertilizers. These elements
promote plant growth in three dierent ways. Nitrogen promotes the growth of leaves and vegetation.
Phosphorus promotes root and shoot growth. Potassium regulates water and nutrient movement.
I6 NUTRIENTS
PLANTS MUST HAVE
The macronutrients, required in
the largest amounts, are nitrogen,
phosphorus and potassium (referred to
by the chemical shorthand N-P-K). Many
of these nutrients may never make it to
your plants if the pH is out of balance.
Needed to produce amino acids..
Essential for plant cell division,
vital for plant growth, directly
involved in photosynthesis,
necessary component of vitamins,
aids in production and use of
carbohydrates and affects energy
reactions in the plant. Helps trap
energy from sunlight.
Deciency causes thin stems,
yellow leaves, slowed growth and
yellowing where plants should
be green.
Helps regulate access to plant
cells. Used for continuous cell
division and formation. Involved
in nitrogen metabolism. Required
for enzyme activation and cell
reproduction. Reduces plant
respiration, aids translocation of
photosynthesis.. Increases fruit set
and stimulates microbial activity.
Deciency halts growing tips, curls
leaves, and causes cell membranes
to disintegrate, producing thin cell
walls and blossom end rot.
Essential component of various
enzyme systems for energy
production, protein synthesis and
growth regulation. Needed to
produce plant growth hormones.
Greatly benefits seed and grain
production and maturation.
Deciency displays yellowing and
mottling of leaves. Plants also
show delayed maturity.
Important for nitrogen fixation,
chlorophyll synthesis and used
in other enzymes and proteins.
Deciency more likely in alkaline
soil. Causes yellowing between
enlarged veins and short, skinny
stems.
Important for nitrogen
metabolism and protein synthesis.
Needed to convert inorganic
phosphates to organic forms.
Deciency occurs mainly in acid
soils. Can cause pale, deformed,
thin leaves.
Needed for genetic material, cell
membranes, root development,
seed number and size. Facilitates
the use of energy, involved in
photosynthesis, respiration, energy
storage and transfer, cell division
and enlargement. Promotes early
root formation. Improves quality of
fruits, vegetables and grains.
Deciency causes purple leaves
beginning underneath, halted
roots, slow growth, poor fruit and
vegetable production.
Needed for the chlorophyll
molecules that put the green
in plants. Also used for enzyme
activation. Improves utilization and
mobility of phosphorus. Increases
iron utilization in plants and
influences earliness and uniformity
of maturity.
Deciency causes yellowing of lower
leaves and, in some cases, lower
crop yield.
Important for reproductive
growth. A catalyst for enzyme and
chlorophyll synthesis. Aids root
metabolism and helps in using
proteins.
Deciency symptoms generally
appear on young plants. First
symptoms are yellowing of youngest
leaves with slightly stunted growth.
In extreme cases, leaves die after
becoming shriveled, twisted, broken
and ragged.
Most soils have enough chloride for
adequate plant nutrition. However,
chloride deficiencies are reported.
Deciency in sandy soils in high
rainfall areas or those derived from
low-chloride parent materials.
There are few areas of chloride-
deciency, so this micronutrient is
not considered in fertilizer programs.
Needed for synthesis of chlorophyll,
assists in vitamin, carbohydrate and
nitrogen metabolism.
Deciency more likely in alkaline
soil. Stops new leaf growth and pale
color, mostly between veins.
Needed for carbohydrate
metabolism. Influences the uptake
of calcium, sodium and nitrogen.
Increases photosynthesis. Essential
to protein synthesis. Important in
fruit formation. Activates enzymes
and controls their reaction rates.
Improves quality of seeds and
fruit, improves winter hardiness,
increases disease resistance.
Deciency leads to abby stems,
halted growth, burnt leaf edges
and vulnerability to disease.
An integral part of amino acids
needed to build proteins.
Contributes to the development
of several enzymes and vitamins.
Aids in seed production and
promotes nodule formation on
legumes. Needed in chlorophyll
formation.
Deciency causes younger leaves
to yellow.
Important for all growing tissues.
Exists in cell membranes. Needed
for nitrogen fixation, protein
synthesis, starch and sugar
transport, root growth, water
uptake and transport.
Deciency more likely in alkaline
soils. May lead to growing points
dying and cells being disrupted.
The secondary nutrients are calcium,
magnesium and sulphur. Most crops
need these three secondary nutrients
in lesser amounts than the primary
nutrients. People are giving them more
prominence in crop fertilization programs
as they learn that N-P-K fertilizers alone
cannot fulfill plant requirements.
NITROGEN (N)
CALCIUM (Ca)
ZINC (Z)
CARBON (C)
IRON (Fe)
MOLYBDENUM (Mo)
PHOSPHORUS (P)
MAGNESIUM (Mg)
COPPER (Cu)
HYDROGEN (H)
CHLORIDE (Cl)
MANGANESE (Mn)
POTASSIUM (K)
SULPHUR (S)
BORON (B)
OXYGEN (O)
In addition to the 13 nutrients above, plants also require carbon,
hydrogen and oxygen. Plants extract these elements from air
and water to make up the bulk of their weight.
UNDERSTANDING
GARDEN
BIOLOGY
30