9Functions of Phosphorus Stimulates early formation and growth of rootsProvides for fast and vigorous growth and speeds maturityStimulates flowering and seed developmentNecessary for the enzyme action of many plant processes
10Phosphorus P Deficiency symptoms decrease in growth slow maturity older leaves are purplish colorP
25Micro Nutrients Also called “trace” elements Needed by plants in small amounts
26Iron (Fe) Functions of Iron Deficiency symptoms Essential for chlorophyll productionHelps carry electrons to mix oxygen with other elementsDeficiency symptomsmottled and interveinal chlorosis in young leavesstunted growth and slender, short stems
30Zinc (Z) Functions Deficiency symptoms plant metabolism helps form growth hormonesreproductionDeficiency symptomsretarded growth between nodes (rosetted)new leaves are thick and smallspotted between veins, discolored veins
32Boron (B) Functions Deficiency Symptoms affects water absorption by rootstranslocation of sugarsDeficiency Symptomsshort, thick stem tipsyoung leaves of terminal buds are light green at baseleaves become twisted and die
41Objective 6.02Discuss the advantages and disadvantages of various fertilizers.
42Types of Fertilizers Complete Incomplete Organic Inorganic Soluble Insoluble
43Complete vs. Incomplete Complete has all three primary nutrients-nitrogen phosphorous & potassiumExamples: , ,Incomplete DOES NOT have all three primary nutrientsExamples: , ,
44Organic FertilizersComes from plant or animal matter and contains carbon compoundsExamples: urea, sludge and animal tankage
45Advantages of Organic Slow release of nutrients Not easily leached from the soilAdd organic components to growing media
46Disadvantages of Organic Hard to getNot sterileLow nutrient contentExpensive
47Inorganic Fertilizers Comes from sources other than animals or plantsChemical products
48Advantages of Inorganic Can make the desired ratio of nutrientseasy to getlower cost
49Disadvantages of Inorganic No organic materialpossible chemical building up in growing media
50Soluble FertilizerDissolve in water and are applied as a liquid solutionFertigationfertilizing through irrigation waterbig advantage
51Insoluble FertilizerIncludes granular and slow release applied to the growing media
52Granular vs. Slow Release relatively inexpensiveeasy to findSlow Releasemore expensive because it is coatedmore uniform release of nutrients over time period
5320-10-20 Fertilizer Analysis N P K Fertilizer analysis expresses weight as a percent of nitrogen, phosphorus and potassiumNPK
54Fertilizer Analysis For Example A 100 pound bag of fertilizer has an analysis of How many pounds of nitrogen, phosphorus and potassium are in the bag?Nitrogen: 100lbs X 15%=15lbsPhosphorus: 100lbs X 5%=5lbsPotassium: 100lbs X 15%=15lbs
55Fertilizer RatiosA fertilizer with a analysis would have a 1:1:1 ratioA fertilizer with a analysis would have a 3:1:2 ratioWhat would be the ratio for a fertilizer with an analysis of ?4:2:3
57BandingPlacing 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.
58SidedressingPlacing a band of fertilizer near the soil surface and to the sides after seedlings emerge from the soil.
59TopdressingMixing fertilizer uniformly into the top one to two inches of growing media around the plant.
60PerforatingPlacing fertilizer in 12”-18” holes drilled 18” to 24” around the canopy drip line of fruit trees. Cover the holes and fertilizer slowly dissolves.
61BroadcastingSpreading fertilizer to cover the entire production area
62Foliar SprayingSpraying micronutrients in a solution directly on plant leaves.Quickly corrects nutrient deficienciesFertilizer concentration should not be too high or leaf burning will occur.
63FertigationIncorporating 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-typePositive-displacement
64Venturi-type Simple and inexpensive less accurate depends on water pressure in the hose and in the smaller tube to proportionExample: Hozon
65Positive-displacement More expensivevery accuratephysically inject and mix specific amounts of concentrated solution and waterExamples: commander proportioners, and Smith injectors
66Rules for applying fertilizers Method used should be practical, effective and cost efficientMethod used affects nutrient availability for plant useFertilizer must be dissolved and reach plant roots