Plant Nutrition & Fertilizers WMAMG 1/31/17 By Dawn Pettinelli UConn Soil Nutrient Analysis Lab dawn.pettinelli@uconn.edu
SOIL-PLANT SYSTEM From: Extension.org Relationships between plants & soils evolved over billions of years. For plant life to endure, needs nutrients. Micro-organisms evolved with plants to break down organic matter symbiotic relationships. Closed system. From: rmsiblog.wordpress.com
SOIL FERTILITY Soil Fertility is defined in terms of both soil nutrient levels and the ability of the plant to recover those nutrients. Soil conditions and cultivation can either favor or adversely affect nutrient release and uptake by the plant.
PLANT NUTRITION INORGANIC SIDE - Includes inorganic elements like Ca +2, NO 3-, Fe +3, etc. ORGANIC SIDE Includes enzymes, hormones, chelated elements, antibiotics, and other substances. Not as much known but doesn t mean less important.
IDEAL SOIL PROVIDES PLANT ROOTS WITH: Evenly distributed water Oxygen for root respiration Oxygen for microbial activity Good pore structure so roots can grow freely and deeply Nutrient supply
SOIL ph & SCALE Soil ph is the measurement of acidity or alkalinity of the soil Graphic by R. Zito, UConn MG 2010
Chart showing a range of ph from 1 to 12 and the approximate ph of produces commonly used in our society every day. From: The Nature and Properties of Soils, 11 th edition by Nyle C. Brady and Ray R. Weil
WHY NEW ENGLAND S SOILS ARE ACIDIC PARENT MATERIAL IS LOW IN BASE CATIONS CARBON DIOXIDE (ROOT/MICROBE RESPIRATION) AND WATER PRODUCES CARBONIC ACID ORGANIC MATTER DECOMPOSITION PRODUCES ORGANIC ACIDS ACID RAIN
A SOIL S ph AFFECTS: NUTRIENT AVAILABILITY ELEMENT TOXICITY MICROBIAL ACTIVITY FATE OF MANY SOIL POLLUTANTS ROOT GROWTH AGGREGATE STABILITY
ph VS NUTRIENT AVAILABILITY WIDTH OF BAR SHOWS THE RELATIVE AVAILABILITY OF EACH NUTRIENT ELEMENT WITH A CHANGE OF SOIL ph. YELLOW AREA OF CHART (6.0 to 7.0) IS A GOOD RANGE FOR MOST GARDEN PLANTS. FROM GARDENS ALIVE CATALOG, 2000
POTATO SCAB CORKY SCABS OR BROWN SUNKEN SPOTS POTATOES DO NOT STORE WELL THOUGH TASTE IS NOT AFFECTED SOILBORNE AFFECTS POTATOES, BEETS, CARROTS, TURNIPS, PARSNIPS MAINTAIN A SOIL ph OF 5.2 OR BELOW
INTERVEINAL CHLOROSIS INTERVEINAL CHLOROSIS IN RHODODENDRON TYPICALLY CAUSED BY IRON DEFICIENCY. THIS MAY ALSO INDICATE OTHER MICRONUTRIENT DEFICIENCIES LIKE ZINC OR MANGANESE AS WELL AS DEFICIENCIES IN MACRO NUTRIENTS. Photo by Carol Lambiase, MG
CHANGING SOIL ph To Lower ph: To Raise ph: Apply Sulfur Apply Acidic Salts of Iron, Aluminum or Ammonium Peat Moss Apply Limestones or Hydrated Lime Soluble Calcium Products Apply Woodashes Compost
AMOUNT OF LIME NEEDED DEPENDS UPON: NECESSARY CHANGE IN SOIL ph CHEMICAL COMPOSITION OF LIMING MATERIAL BUFFERING CAPACITY OF SOIL
FERTILIZER EFFECTS ON SOIL REACTION Ammonium-N based fertilizers are ACIDIC They lower ph Nitrate-N based fertilizers are BASIC They raise ph The soil ph change is temporary!
ESSENTIAL ELEMENTS C HOPKNS CaFe Mg B Mn CuZn Mo and Cl NiCo
MACRONUTRIENTS - GROUP I SUPPLIED BY AIR AND WATER: CARBON HYDROGEN OXYGEN ARE THE BUILDING BLOCKS OF PLANT LIFE CO 2 + H 2 0 = C 6 H 12 O 6 + O 2 Illustration from Botany for Gardeners by Brian Capon, 1990
MACRONUTRIENTS - GROUP II NITROGEN PHOSPHORUS POTASSIUM THESE THREE ELEMENTS OCCUR NATURALLY IN THE SOIL BUT OFTEN IN LIMITED AMOUNTS. WE COMMONLY ADD THESE NUTRIENTS BY FERTILIZING.
MACRONUTRIENTS - GROUP III CALCIUM MAGNESIUM SULFUR THEY OCCUR IN SOILS NATURALLY BUT IN VARYING AMOUNTS. WE SUPPLY Ca AND Mg WITH LIMESTONE OR OTHER AMENDMENTS LIKE SUPERPHOSPHATE. S IS USUALLY SUPPLIED BY ACID RAIN IN OUR PART OF THE COUNTRY.
MICRONUTRIENTS - GROUP IV BORON COPPER IRON MANGANESE MOLYBDENUM ZINC CHLORINE POSSIBLY Si, Co, Ni Micronutrients or trace elements are needed in very small amounts, ie. an acre of corn only uses 1/2 ounce boron!!!! Naturally supplied by soil but ph affects availability. Often added to synthetic fertilizers, generally present in natural organic fertilizers
HEAVY METALS - 5 METALLIC IONS THAT TO A GREATER OR LESSER DEGREE ARE TOXIC TO HUMANS AND OTHER ANIMALS. SOME ARE REQUIRED BY PLANTS IN TINY AMOUNTS. THEY INCLUDE ARSENIC, CADMIUM, CHROMIUM, COPPER, LEAD, MERCURY, NICKEL AND ZINC
HOW NUTRIENTS BECOME AVAILABLE Weathering of Minerals Soil Chemical Reactions Dissolve Larger Compounds Rain Carries Nutrients From Atmosphere Microbial Decomposition of Organic Matter Fertilizer/Limestone Application
HOW NUTRIENTS TAKEN UP ROOT INTERCEPTION - Absorbed from soil solution at root surfaces MASS FLOW - As plants transpire, water is lost through leaves and then replaced through roots DIFFUSION - Nutrients move from areas of greater to lesser concentrations
Plant Growth Vs. Nutrient Concentration Graphics by R. Zito, MG 2010
FACTORS CONTROLLING NUTRIENT SUPPLY AND UPTAKE Soil Moisture Soil Air Soil ph Soil Organisms Soil Compaction Soil Temperatures Nutrient Interactions Amount of Organic Matter
NITROGEN PART OF ALL LIVING CELLS STIMULATES GREEN LEAFY GROWTH PLANTS TAKE UP MOSTLY AS NO 3 AND SOMETIMES NH 4 DEFICIENCY SYMPTOMS INCLUDE SMALL LEAVES, YELLOWING OR SHORT, THIN GROWTH
NITROGEN CYCLE
PHOSPHORUS NECESSARY FOR PHOTOSYNTHESIS, FLOWERING, FRUITING AND MATURATION ENCOURAGES ROOT GROWTH COMPONENT OF DNA DEFICIENT PLANTS MAY BE STUNTED OR SPINDLY, DARK GREEN, PURPLISH OR YELLOW COLOR
PHOSPHORUS EFFICIENCY VS ph 100 90 80 70 60 50 40 30 20 10 0 ph 5.0 ph 6.0 Ph 6.5-7.0 Relative Efficiency
POTASSIUM REMAINS IN IONIC FORM IN PLANT CELL, ACTS AS AN ACTIVATOR FOR CELLULAR ENZYMES HELPS REDUCE WATER LOSS FROM STOMATES AND INCREASES ROOT CELLS ABILITY TO TAKE UP WATER HELPS PLANTS ADAPT TO ENVIRONMENTAL STRESS IMPROVES FLAVOR, COLOR AND STEM STRENGTH
AVAILABILITY OF NUTRIENTS REDUCED BY: REMOVAL OF BIOMASS (HARVEST AND WEEDING) LEACHING PRECIPITATION INTO INSOLUBLE COMPOUNDS
SOIL TESTING Consider your soil a storehouse for plant nutrients, a pantry of sorts. A soil test is a means to take a chemical inventory of the available nutrients in your soil. Can tell if you need more nutrients or if the shelves are overstocked.
WHICH ONE TO CHOOSE? Graphic by R. Zito, MG 2010
FERTILIZERS AND AMENDMENTS A FERTILIZER is any material added to soil in order to supply plant nutrients. Comes with a guaranteed analysis. An AMENDMENT improves aeration, drainage, structure, fertility and the ability of the soil to hold water and nutrients (and it may or may not supply nutrients)
FERTILIZER GRADES THE 3 NUMBERS ON THE FRONT OF THE LABEL ARE REFERRED TO AS THE GRADE OR GUARANTEED ANALYSIS. THEY STAND FOR THE MINIMAL AMOUNTS OF TOTAL NITROGEN (N), AVAILABLE PHOSPHATE (P 2 O 5 ) AND WATER SOLUBLE POTASH (K 2 O) BY PERCENT DRY WEIGHT
FERTILIZER RATIOS GRADE 20-20-20 5-10-5 13-24-12 12-4-8 20-4-8 0-45-0 RATIO 1:1:1 1:2:1 1:2:1 3:1:2 5:1:2 0:1:0
GUARANTEED ANALYSIS THIS FERTILIZER CONTAINS ALL WATER SOLUBLE NITROGEN(WSN). IT ALSO CONTAINS MAGNESIUM, SULFUR, IRON AND MANGANESE. ALL THESE NUTRIENTS ARE FROM INORGANIC SOURCES.
BEST FERTILIZER TO USE DEPENDS ON: NUTRIENTS NEEDED SOIL TEXTURE AMOUNT OF SOIL ORGANIC MATTER METHODS OF APPLYING FERTILIZER YOUR TIME AND EFFORTS
TYPES OF FERTILIZERS NATURAL/ORGANIC includes fertilizers derived from the remains or a by-product of a plant or animal (manures, composts, seaweed, bonemeal) as well as untreated mined materials (rock minerals) SYNTHETIC FERTILIZERS are materials that have been chemically altered, manufactured and/or synthesized.
COMPARISON OF FERTILIZERS CONVENTIONAL FERTILIZERS ADVANTAGES FAST ACTING LOW COST HIGHER NUTRIENT CONTENT SO LESS IS NEEDED SOME ARE ACID-FORMING DISADVANTAGES GREATER BURN POTENTIAL MAY REQUIRE MORE FREQUENT APPLICATIONS NUTRIENTS READILY LEACH ENERGY USED FOR PRODUCTION NATURAL/ORGANIC FERTILIZERS ADVANTAGES LOW BURN POTENTIAL RELATIVELY SLOW RELEASE CONTAINS MICRONUTRIENTS IMPROVES SOIL CONDITIONS ENCOURAGES SOIL ORGANISMS INCREASES ORGANIC MATTER DISADVANTAGES EXPENSIVE PER LB NUTRIENT BULKY ODOR SLOW NUTRIENT RELEASE WEED SEEDS/HEAVY METALS
HARVESTING ROCK MINERALS NEARLY 90 YEARS OF MINING HAVE TURNED 80% OF NAURU INTO A LUNAR LANDSCAPE OF BARE CORAL PINNACLES NATIONAL GEOGRAPHIC MINING FOR PHOSPHATE, A RICH FERTILIZER BASE
FORMS OF FERTILIZER WATER SOLUBLE POWDERS GRANULAR SOLIDS SLOW RELEASE PELLETS LIQUIDS SPIKES/TABLETS PLANT/ANIMAL MEALS
SPECIALTY FERTILIZERS GARDEN FERTILIZER 5-10-5 ROSE FOOD 5-9-6 FLOWER FOOD 7-7-7 AZALEA AND EVERGREEN FOOD 10-4-6 TOMATO FOOD 5-10-10 BULB FOOD 3-10-6 CITRUS FOOD 12-6-8 PALM FOOD 10-6-6
GROWTH ENHANCING SUBSTANCES CHELATING AGENTS ENZYMES HUMIC ACID PLANT HORMONES
APPLICATION METHODS BROADCASTING BANDING STARTER SOLUTIONS FOLIAR FEEDING FERTILIZER SPIKES OR STAKES LIQUID SOIL INJECTION DRILL OR PUNCH BAR HOLES IN SOIL LIQUID SURFACE APPLICATION
TIMING OF FERTILIZER APPLICATIONS INFLUENCED BY TYPE OF CROP MOST LANDSCAPE PLANTS AND PERENNIALS FERTILIZED IN SPRING BULBS FERTILIZED IN FALL FERTILIZE LAWNS SPRING AND FALL INCORPORATE FERTILIZER INTO ANNUAL AND VEGETABLE BEDS BEFORE PLANTING, SIDEDRESS IF NECESSARY USE A 6 MONTH SLOW RELEASE FOR CONTAINERS OR A WATER SOLUBLE AS DIRECTED (USUALLY EVERY 7 TO 10 DAYS)