2. Nutrient Requirements of Plants
Plants can grow in soil or soilless mediums
But, nutrients must be readily available
There are 16 essential plant nutrients
Carbon, hydrogen and oxygen are the most important
Macronutrients: Nutrients which are needed in large quantities for good plant growth
Micronutrients: Essential for plant growth but in smaller quantities

3. Primary Macronutrients
Nitrogen (N) – Largest quantities, most noticeable and quickest effect on plants
Leaf growth and dark green leaves
Phosphorus (P) – Required in less amount than N and K
Strong root systems, brighter and more beautiful flowers, and rapid growth
Potassium (K) – Third primary macronutrient
Produces and matures the seed, improves fruit keeping quality, and decreases the water requirement

4. Secondary Macronutrients
Needed in smaller quantities than primary macronutrients but larger quantities than micronutrients
Calcium (Ca) – Promotes root formation
Sulfur (S) – Promotes root growth
Magnesium (Mg) – Affects the intake of plant nutrients

5. Micronutrients
Essential for plant growth but needed in very small quantities
If they are not available plants cannot absorb and use the other available nutrients to complete their biological functions
Available as a granular fertilizer and in FRITTED FORM which means elements are released slowly into the soil or potting medium
Iron (Fe)
Boron (B)
Manganese (Mn)
Molybdenum (Mo)
Zinc (Zn)
Chloride (Cl)
Copper (Cu)

6. Commercial Fertilizers
Fertilizer is a soil supplement which is used to provide essential nutrients to plants
Organic Fertilizer: Naturally occurring fertilizer
Inorganic Fertilizer: Manufactured with chemicals
Traditionally there are three fertilizer forms:
Dry – Usually granular form
Liquid – Soluble fertilizer
Controlled Release – Release over an extended period of time
Water-soluble is mixed with water and dissolved before being applied

7. Application Methods Water hose and water breakers
Small droplets for general watering
Smaller droplets for watering seedlings
Tiny droplets for misting
A wand attachment is used for hard to reach areas
Hose end sprayers
Fertilizer is mixed with water in a container attached to the hose

8. Application Methods
Fertilizer Injectors: Add water soluble fertilizers to the main water line
Or, incorporate or mix fertilizer into potting mix
Timed-release fertilizers incorporated into seedling and potting mix provide nutrients for 3-4 months
Trees, shrubs, and large vegetable plants:
Bury fertilizer pills, capsules, or spikes in the ground
Top dressing requires solid or spray fertilizers to be hand worked into large pots, around individual plant base, or into garden soil

9. Fertilizer Storage and Handling
Keep fertilizer dry at ALL times!!
Store away from concrete floors
Keep bags sealed to keep out moisture
Keep in a locked room away from children
High nitrogen-content fertilizers can explode so do not explore them for long periods of time

10. The Fertilizer Bag
The brand name and/or the chemical compound will be listed on the label
Fertilizer type: pelleted, prill, granular
Guaranteed analysis: The known amount of nutrients within the product
Name and address of manufacturer

11. Guaranteed Analysis of Fertilizers
Complete fertilizers proved nitrogen, phosphorus, and potassium in varying quantities
Example: 10 – 20 – 10
Incomplete fertilizers contain percentages of one or two of the three primary macronutrients
Example: Urea (46 – 0 – 0)
The remaining ingredients are not contributing to nutritional value
Invert ingredients