Transcript Soil Nutrients and Fertilizers

Soil Nutrients and
Fertilizers
Essential Standard 6.00- Explain the role
of nutrients and fertilizers.
Objective 6.01
• Discuss macro and micro nutrients and
the role they play in plant deficiencies.
Macro vs Micro Nutrients
• Macronutrients (aka primary nutrients) –
nutrients that plants need in large
amounts
• Micronutrients (aka trace elements) –
nutrients that plants need in small
amounts
Macronutrients
• Non-mineral
elements
– carbon (C)
– hydrogen (H)
– oxygen (O)
Macronutrients
• Primary Nutrients
– Nitrogen (N)
– Phosphorus (P)
– Potassium (K)
Nitrogen (N)
Functions:
• Promotes growth of leaves and stems
• Gives dark green color and improves
quality of foliage
• Necessary to develop cell proteins and
chlorophyll
Nitrogen (N)
Deficiency symptoms
• sick, yellow-green leaves
• short stems, small leaves, pale colored
leaves and flowers
• slow and dwarfed plant growth
Nitrogen deficiency
Phosphorus (P)
Functions
• Stimulates early formation and growth of
roots
• Provides for fast and vigorous growth and
speeds maturity
• Stimulates flowering and seed
development
Phosphorus (P)
Deficiency symptoms
• decrease in growth
• slow to maturity
• older leaves are purplish color
Phosphorus Deficiency
Potassium (K)
Functions
• Used to form carbohydrates and proteins
• Formation and transfer of starches, sugars
and oils
• Increases disease resistance, vigor and
hardiness
Potassium (K)
Deficiency symptoms
• mottled, spotted, streaked or curled
leaves
• scorched, burned, dead leaf tips and
margins
Potassium Deficiency
Macronutrients
• Secondary Nutrients
– calcium (Ca)
– magnesium (Mg)
– sulfur (S)
Calcium (C)
Functions
• Improves plant vigor
• Influences intake and synthesis of other
plant nutrients or elements
• Important part of cell walls
Calcium (C)
Deficiency symptoms
• small developing leaves
• wrinkled older leaves
• dead stem tips
Calcium Deficiency
Magnesium (Mg)
Functions
• Influences the intake of other
essential nutrients
• Helps make fats
• Assists in translocation of
phosphorus and fats
Magnesium (Mg)
Deficiency symptoms
• Interveinal chlorosis - yellowing of
leaves between green veins
• leaf tips curl or cup upward
• slender, weak stalks
Magnesium Deficiency
Sulfur (S)
Function
• Promotes root growth and vigorous
vegetative growth
• Essential to protein formation
Sulfur (S)
Deficiency symptoms
• young leaves are light green with lighter
color veins
• yellow leaves and stunted growth
Sulfur Deficiency
Micro nutrients
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Iron (Fe)
Copper (Cu)
Zinc (Zn)
Boron (B)
Molybdenum (Mo)
Manganese (Mn)
Chlorine (Cl)
Iron (Fe)
• Functions of Iron
– Essential for chlorophyll production
– Helps carry electrons to mix oxygen with
other elements
• Deficiency symptoms
– mottled and interveinal chlorosis in young
leaves
– stunted growth and slender, short stems
Iron Deficiency
Copper (Cu)
• Functions
– Helps in the use of Iron
– Helps respiration
• Deficiency symptoms
– young leaves are small and permanently
wilt
– multiple buds at stem tip
Copper Deficiency
Zinc (Z)
• Functions
– plant metabolism
– helps form growth hormones
– reproduction
• Deficiency symptoms
– slows growth between nodes (rosetted)
– new leaves are thick and small
– spotted between veins, discolored veins
Zinc Deficiency
Boron (B)
• Functions
– affects water absorption by roots
– translocation of sugars
• Deficiency Symptoms
– short, thick stem tips
– young leaves of terminal buds are light
green at base
– leaves become twisted and die
Boron Deficiency
Molybdenum (Mo)
• Functions
– plant development
– reproduction
• Deficiency symptoms
– stunted growth
– yellow leaves, upward curling leaves, leaf
margins burn
Molybdenum Deficiency
Manganese (Mn)
• Functions
– plant metabolism
– nitrogen transformation
• Deficiency symptoms
– interveinal chlorosis
– young leaves die
Manganese Deficiency
Chlorine (Cl)
• Functions
– essential to some plant processes
– acts in enzyme systems
• Deficiency symptoms
– usually more problems with too much
chlorine or toxicity than with deficiency
Chlorine Deficiency
Super Hero Nutrient Posters
Working in groups of three, you will make a poster that will
highlight one of the nutrients we discussed in our notes.
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Pick a nutrient
Make a super hero name for your nutrient (ex – Zorro Zinc)
Draw and color your super hero (use your imagination!)
Include the following:
- Name of the nutrient
- What is does for the plant
- Signs of a deficiency
- Colored drawing of a leaf showing the deficiency
symptoms
Fertilizers
Objective 6.02
• Discuss the advantages and
disadvantages of various fertilizers.
Types of Fertilizers
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Complete
Incomplete
Organic
Inorganic
Soluble
Insoluble
Complete vs. Incomplete
• Complete has all three primary
nutrients-nitrogen phosphorous &
potassium
– Examples: 10-10-10, 15-30-15, 20-5-20
• Incomplete DOES NOT have all three
primary nutrients
– Examples: 20-0-0, 0-20-0, 12-0-44
Organic Fertilizers
• Comes from plant or animal matter and
contains carbon compounds
• Examples: urea, sludge and animal
tankage
Advantages of Organic
• Slow release of nutrients
• Not easily leached from the soil
• Add organic components to growing
media
Disadvantages of Organic
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Hard to get
Not sterile
Low nutrient content
Expensive
Inorganic Fertilizers
• Comes from sources other than animals
or plants
• Chemical products
Advantages of Inorganic
• Can make the desired ratio of nutrients
• easy to get
• lower cost
Disadvantages of Inorganic
• No organic material
• possible chemical building up in growing
media
Soluble Fertilizer
• Dissolve in water and are applied as a
liquid solution
• Fertigation
– fertilizing through irrigation water
– big advantage
Insoluble Fertilizer
• Includes granular and slow release
applied to the growing media
Granular vs. Slow Release
• Granular
– relatively inexpensive
– easy to find
• Slow Release
– more expensive because it is coated
– more uniform release of nutrients over time
period
Fertilizer Analysis
• Fertilizer analysis expresses weight as
a percent of nitrogen, phosphorus and
potassium
20-10-20
Fertilizer Analysis
• For Example
– A 100 pound bag of fertilizer has an
analysis of 15-5-15. How many pounds of
nitrogen, phosphorus and potassium are in
the bag?
• Nitrogen: 100lbs X 15%=15lbs
• Phosphorus: 100lbs X 5%=5lbs
• Potassium: 100lbs X 15%=15lbs
Fertilizer Ratios
• A fertilizer with a 10-10-10 analysis
would have a 1:1:1 ratio
• A fertilizer with a 24-8-16 analysis would
have a 3:1:2 ratio
• What would be the ratio for a fertilizer
with an analysis of 36-18-27?
4:2:3
Application Procedures
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Banding
Sidedressing
Topdressing
Perforating
Broadcasting
Foliar spraying
Fertigation
• Assignment:
– Work with your group to
define the fertilizer
application method you
are assigned
– Draw a picture of the
method
– Give me a pro and a con
Banding
• Placing a band of fertilizer about two
inches to the sides and about two
inches below seed depth.
• DO NOT place below the seeds
because fertilizer will burn the roots.
Sidedressing
• Placing a band of fertilizer near the soil
surface and to the sides after seedlings
emerge from the soil.
Topdressing
• Mixing fertilizer uniformly into the top
one to two inches of growing media
around the plant.
Perforating
• Placing fertilizer in 12”-18” holes drilled
18” to 24” around the canopy drip line of
fruit trees. Cover the holes and fertilizer
slowly dissolves.
Broadcasting
• Spreading fertilizer to cover the entire
production area
Foliar Spraying
• Spraying micronutrients in a solution
directly on plant leaves.
• Quickly corrects nutrient deficiencies
• Fertilizer concentration should not be
too high or leaf burning will occur.
Fertigation
• Incorporating water-soluble fertilizer into
the irrigation system of greenhouse and
nursery crops.
• Concentrated solutions usually pass
through proportioners or injectors to
dilute to the correct ratio.
– Venturi-type
– Positive-displacement
Venturi-type
• Simple and inexpensive
• less accurate
• depends on water pressure in the hose
and in the smaller tube to proportion
• Example: Hozon
Positive-displacement
• More expensive
• very accurate
• physically inject and mix specific
amounts of concentrated solution and
water
• Examples: commander proportioners,
and Smith injectors
Rules for applying fertilizers
• Method used should be practical,
effective and cost efficient
• Method used affects nutrient availability
for plant use
• Fertilizer must be dissolved and reach
plant roots