1. Training and Fruit Trees 2. Nutrition and Fertilizers

Chuck Ingels UC Cooperative Extension, Sacramento County

Advanced Master Gardener Training – Riverside April 4, 2014 Pruning Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Reasons for Training Young Fruit Trees

 Create light penetration in lower tree  Support load  Create access for ladder work, fruit thinning, harvesting, etc. Ornamental vs. Fruit & Nut Trees Differences

Landscape Trees Fruit & Nut Trees  Taller trees  Shorter trees  Central leader training  Many training methods  First branch higher  First branch lower  Mostly winter pruning  Winter, summer pruning  Few if any heading cuts  Some heading cuts  Branch spreaders rarely  Branch spreaders used common Ornamental vs. Fruit & Nut Trees Similarities

 Branches carry heavy load »Length vs. fruit load  No narrow branch (crotch) angles  Proper pruning cuts for wound closure  May require support »Cabling vs. rope or stake Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Post-Planting Care

• Head tree at 18-36 in. (bare root only) • Cut back well-placed laterals to 3-8 in., remove all others • Paint trunk white Interior latex paint & water, 50:50 Entire trunk & 2 in. below Prevents sunburn & borers

Pruning a Bare-Root Tree

Branches thinner Branches thicker than 3/16 than 3/16 New on Branches of Newly Planted Tree Paint Trunks White (Hot Climates, Afternoon Sun on Trunk)

To prevent this Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Semi-Dwarf vs. Genetic Dwarf

• Standard: 20-25+ ft. • Semi-dwarf (dwarfing rootstock): 12-20 ft. Variable dwarfing • Genetic dwarf (std. rootstock): 8-12 ft. Available in apricot, , olive, peach, nectarine, pomegranate Selection of varieties is limited Not available in citrus, fig, , persimmon, / pluot Genetic Dwarf Peach/Nect. INTERNODE LENGTH Standard Peach Genetic Dwarf Peach Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

More Fruit Tree Terms

• Scaffold branch: main structural limb • Spur: short fruiting twig • : current season elongated growth • Water sprout: vigorous shoot from branch • Sucker: shoot from rootstock or roots Apricot Spurs

Cherry

A. pear Eur. pear Peach Fruiting Branches

Flower

Veg. Heading Cut

• Removal of part of branch or shoot • Used to promote branch development, especially on young trees • Stimulates growth just below cuts • Can reduce sunlight penetration Thinning Cut

• Removal of entire branch or shoot, or back to a branch >1/3 the thickness of cut branch • Used to prevent crowding and improve sunlight penetration • Defines main branches Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Summer Pruning of Young Trees

• Purpose: promote scaffold branches • Head unwanted shoots to 4-6 in. • Pinch 2 ft. long shoots to promote side branching if necessary • Reduces training time, shortens time to first fruit production Summer Pruning for Training (Open Center)

Before After Summer Pruning of Mature Trees

• Purpose: To increase sunlight & productivity of lower fruiting • Remove unwanted vigorous, upright shoots 1-2 times during season • Bring down tree height • Large branches may sunburn if pruning is excessive Summer Pruning (Plum)

Before

After Prune Apricots and Cherries in August to Avoid Branch Diseases Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Tree Shape Determines Light Interception

Sunlight > ~ 1.5 X Sunlight 1 X

Shade

Shade Sunlight Sunlight Shade Improving Light Management

Sunlight > ~ 2 X •More fruit color Sunlight •Strong buds Sunlight Sunlight •Strong •Larger fruit Shade

Shade Specific Fruit & Nut Tree Training Methods

• Open center • Central leader • Modified central leader • Perpendicular “V” • Fruit bush • Espalier Open Center

• Most common method • Stone fruits and ; can also use for , , figs • Select scaffolds during first 2 growing seasons, touch up in dormant season • Keep center open during summer from the start Pruning a One-Year-Old Peach Pruning a Two-Year-Old Peach Pruned Three-Year-Old Peach Pruning a Mature Peach Mature Peach/Nectarine Tying Open Center Peach Tree Removing Old Fruiting Wood

Cut back 2-year- old branches to healthy 1-year- old branches Prune Apricots in August to Avoid Eutypa Dieback Specific Fruit & Nut Tree Training Methods

• Open center • Central leader • Modified central leader • Perpendicular “V” • Fruit bush • Espalier Central Leader Apple (Genetic Dwarf, planted 2000)

2004 2013 Central Leader Training

• Used for apples, pears, Asian pears • Maintain leader, remove at certain height • Tie or stake lateral branches outward • Create 3-4 whorls of branches • Branches offset from those below Central Leader Training Spread Shoots When Young Spread branches, keep leader dominant Persimmon (FOHC) Central Leader Persimmon

 Bears laterally on current season’s growth  Terminal & first few lateral buds on 1- year-old branches are mixed »Both male & female flowers Persimmon Bearing Habit Persimmon Fruitful Shoots at Tips of 1-Year-Old Branches Training Young Persimmons

 Modified central leader  3 - 5 main scaffolds » 1 foot intervals » 1st & 2nd year can pinch shoots to promote branching. » Head branch ends you want to keep growing into scaffolds. Unheaded Branches on Young Trees – Lost Scaffold Branches, Sunburn Pruning Mature Persimmons

 Dormant, annual pruning  Primarily small cuts  Thin out to invigorate and increase fruit size Before Mature Tree – Mod. Central Leader

After Specific Fruit & Nut Tree Training Methods

• Open center • Central leader • Modified central leader • Perpendicular “V” • Fruit bush • Espalier Fruit Bushes Kept at Desired Height

Fruit Bushes Pruning – Years 1 & 2

• At planting, head trees to 18-24 in. • Mid-spring – cut back new growth by half • Mid-summer – cut subsequent growth back by half • Thinning cuts for sunlight penetration • May need to prune 1-2 more times Cutting New Shoots in Half Mid-Summer Fruit Bushes Pruning Mature Trees

• Cut back new growth above selected tree height 2-3 times during growing season • Thinning cuts for sunlight penetration Mature Fruit Bush Maintaining Tree Height

Before After Cherry, Pome Fruits Ideal for Fruit Bush Apricot, Plum/Pluot Fruit Bushes Vigorous Growth – Extra Work Apricot, Plum/Pluot Fruit Bushes Vigorous Growth

Before After Fruit Bushes

• Advantages Tree maintenance without ladder Trees for small spaces Sequential ripening • Disadvantages Less fruit No shade Timing of pruning critical Key Summer Pruning Missed Excess Shading Loss of lower branches Specific Fruit & Nut Tree Training Methods

• Open center • Central leader • Modified central leader • Perpendicular “V” • Fruit bush • Espalier Espalier Angle Shoots Upward Initially Espalier Pruning Growing Season

Source: Pruning and Training (Amer. Hort. Soc.) Dormant Pruning

Before

After Espalier Menorah Shape Citrus Espalier (Mandarin) Espalier Ensure Adequate Sunlight Espalier Peach

Peach Cherry Espalier Peach Row cover (Agribon)

Spring Pruning of Mature Peach Tree Prune to 1 bud all but 2 shoots per branch

After harvest cut branch back to lower shoot Peach Espalier April 3, 2014 Peach Espalier April 3, 2014 Topics to be Covered

 Pruning Ornamental vs. Fruit Trees  Post-Planting Pruning  Dwarfing  Fruiting Structures and Cut Types  Summer Pruning  Specific Training Methods  Odd and Overgrown Trees

Peach Apple Fruit bent branches Pear Persimmon Before

Poor scaffold branch structure Persimmon Before After

Stake upright Methods of Reducing Height of Large Trees

1. Cut to desired height in thirds over 3 years  Thin upright shoots in summer to provide light for lower fruiting wood Pruning Overgrown Apple

What else can be done? Sunburn from First Topping Methods of Reducing Height of Large Trees

1. Cut to desired height in thirds over 3 years  Thin upright shoots in summer to provide light for lower fruiting wood 2. Bring down height in one year  Saw off limbs well below desired height  Leave one “nurse” limb to feed roots  Thin new shoots, train tree as desired  Paint exposed limbs white Pruning Overgrown Apple – One Year

1999 1999 2012

2012 Fertilization Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Cation Exchange Capacity (CEC)

 A measure of soil fertility  Clay and humus particles have neg. charge  Varies by soil type and % organic matter

+ NH4 Typical CECs Based on Soil Texture

Soil Texture Typical CEC Range meq/100g Sand 2 – 6 Sandy Loam 3 – 8 Loam 7 – 15 Silt Loam 10 – 18 Clay & Clay Loam 15 – 30 Low vs. High CEC

CEC 1-10 CEC 11-50  High sand content  High clay or OM content  N & K leaching more  Greater capacity to hold likely nutrients  Less lime or sulfur  More lime or sulfur needed to adjust pH needed to adjust pH  Low water-holding  High water-holding capacity capacity Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Essential Plant Nutrients

Major Major (Macro) Minor (Micro) Nutrients from Nutrients Nutrients Air & Water from Soil from Soil Carbon Nitrogen Iron Hydrogen Phosphorus Zinc Oxygen Potassium Manganese Calcium Copper Magnesium Chlorine Sulfur Boron Molybdenum Mobility of Nutrients

Ionic Form Soil Mobility Plant Mobility + N NH4 Immobile Immobile - N NO3 Mobile Mobile - P H2PHO4 Immobile Immobile K K+ Immobile Mobile Ca Ca++ Immobile Immobile Mg Mg++ Immobile Mobile Zn Zn++ Immobile Immobile Mn Mn++ Immobile Immobile Roles of Nitrogen (N)

 Converts to amino acids in plant »Building blocks for proteins »Essential for cell division & plant growth  Necessary for enzyme reactions  Constituent of chlorophyll (photosynthesis)  Promotes vigorous vegetative growth “Simplified” Nitrogen Cycle

Biol. N Fix. Organics,manure, Inorganic fertilizers (legumes) compost

Inorganic nutrients Example -Nitrate

Soil organic matter Plant residues, microbes, humus, microbial by- products, etc. leaching harvest Movement of Nitrogen

-  Taken up by plants primarily as nitrate (NO3 ) + » Plant roots can absorb ammonium (NH4 ) but it is often bound to soil and cannot move as easily to roots  Leaching from root zone occurs easily  Deficiency appears on older first because N is mobile Roles of Phosphorus (P)

 Plays role in photosynthesis, respiration, energy storage & transfer, cell division & enlargement  Stimulates early growth & root formation  Promotes and fruit development  Promotes seedling root growth  Contributes to disease resistance  Does not easily leach Roles of Potassium (K)

 Essential for photosynthesis  Used for protein synthesis & sugar translocation  Important in membrane permeability  Opening & closing of stomates  Helps plant use water more efficiently by promoting turgidity  Increases disease resistance Nutrient Analysis Soil Sampling

 Doesn’t always tell what plants take up  Good for baseline info and detecting deficiencies  Sample in rooting zone from different areas  Include at least 1 pint per sample in a quart plastic zip-lock bag, take to lab » See http://cagardenweb.ucdavis.edu  Include: Total N, NO3-N, P, K, Ca, Mg, soil texture, pH, OM, CEC, salts(?) Nutrient Analysis Plant Tissue Sampling

 Tells what plant actually took up  Standards only available for crop plants  Best timing » Annual – during active growth » Tree crops – July » Grapes – at bloom (petioles)  Include 30+ leaves/sample  into small paper bag, refrigerate, take to lab ASAP  Include: N, P, K, Fe, Mn, Zn, salts(?) Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Should I Use Fertilizers?

rarely contain all required nutrients

 Equally rare for garden soil to be deficient in several nutrients

 Add only the nutrients that are deficient Making of Chemical Nitrogen Fertilizers

 Natural gas = 98% methane (CH4)

 Chemical reactions  hydrogen gas (H2)

 Air = 78% N2  Haber-Bosch Process:

 High pressure & heat  Makes ammonia (NH3)

Anhydrous ammonia Conversions of Ammonia to Various N Fertilizers Examples of Chemical Nitrogen Fertilizers

 Ammonium sulfate (21-0-0-24S)  Ammonium nitrate (34-0-0)  Urea (46-0-0)  Highest %N; protein substitute in

animal feeds Slow-Release N Fertilizers

 Synthetic  UF (urea formaldehyde), MU (methylene urea), IBDU (isobutylidenediurea) (uncoated; short & long-chain polymers)  Polymer-coated (e.g., Osmocote)  Longer lasting, not readily leached  Label says “Slow Release Nitrogen”  Water Insoluble Nitrogen (W.I.N.)  Natural (e.g., compost, feather meal) Polymer-Coated Fertilizer Potassium Fertilizers

 Mined, not manufactured  KCl = Muriate of potash

 KSO4 = Sulfate of potash

 KCO3 = Potassium carbonate

 Mining and potash history to be discussed later Fertilizer Analysis

N - P - K - S

21 - 0 - 0 - 24

Ammonium Sulfate Fertilizer Content

 By law, guaranteed content of fertilizer must be stated on bag

 Expressed as % of each plant nutrient applied

 N - P - K ‘Complete’ Fertilizers

Contain at least: Nitrogen (N)  % nitrogen (N) Phosphorus (P)

 % phosphoric acid P2O5 Potassium (K)

 % potash K2O

Examples of Fertilizer Blend Ratios

Ratio 1-1-1 (e.g., 16-16-16): General purpose 2-1-1: Orn. & fruit trees, estab. lawns, leafy veggies 1-2-2: New lawns 1-2-1: Vegetables, seedlings, flowers, bulbs 0-1-1: Woody plants in fall Fertilizer Blends

 N-P-K numbers not always the same

 “Complete” fertilizer = Contains N, P, & K

 “Balanced” fertilizer = Equal amounts of N-P-K

 Examples: 16-16-16 (multi-purpose), 12-4-8 (fruit tree & vine), 5-10-10 (tomato & veg.), 4-8- 5 (camellia/azalea), 25-6-4 (lawns)

 Blends are not standardized! Chelating Agents (Chelates)

 Synthetic organic substances that maintain Fe, Cu, Mn, and Zn in water-soluble form  Makes them readily absorbed by plants  Can be used to correct chlorosis (yellowing) of leaves  But best to lower soil pH Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Vegetable Fertilization Veg. Basics, UC Pub. 8059

 Preplant: N-P or N-P-K  Use 1/3 lb. N per 100 sq. ft.  Dry steer manure: 100 lb. per 100 sq. ft.  Chicken manure: 20 lb. per 100 sq. ft.  Side dressing when plants 3-4” high  0.4 lb. N per 100 sq. ft.  Banded application Fruit & Nut Tree Fertilization The Home , UC Pub. 3485

 Pounds per year of N to correct a deficiency:  Large fruit trees: 1 lb.  Small fruit trees: 0.5 lb.  Large nut trees: 2 lbs.  Small nut trees: 1 lb. Landscape Tree Fertilization Planting Landscape Trees, UC Pub. 8046

“Adding fertilizer, soil amendments, or root stimulants to the planting hole or backfill soil is not recommended. Most nursery-grown trees are well fertilized during production and seldom respond to fertilizing at planting except in the most infertile soils.” Tree Fertilization Points to Remember

 Trees adapted to low soil N levels!  Routine N-P-K fertilization unjustified unless deficiency exists  High N wasteful, polluting, and may increase pest problems  Trees in turf may not require fertilization  Use compost, wood chip mulch  Use slow release fertilizers FERTILIZING “Adding fertilizer, soil amendments, or root stimulants to the planting hole or backfill soil is not recommended. Most nursery-grown trees are well fertilized during production and seldom respond to fertilizing at planting except in the most infertile soils.”

Nutrient Deficiencies are Rare in Woody Ornamentals

 N – Sandy, overwatered, or sub soils  P – Deficient in foothills  Ca, Mg – Acidic or sandy soils  Fe, Mn, Zn, B – High-pH or waterlogged soils Lawn Fertilization Practical Lawn Fertilization, UC Pub. 8065

 Cool-season grass: 4 lbs. actual N/year  Low N & water using species (buffalograss, Zoysiagrass): 2 lbs. actual N/year  Slightly less where grasscycling is used  Up to 1 lb. N/application  Organic and slow-release fertilizers: Can use higher rate & fewer applications

Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Soil Organic Matter

 Serves as energy source (food) for microorganisms, which promote stable aggregation of the soil particles  Essential nutrients are obtained by plants as organic matter decomposes  Enhanced by OM additions but destroyed by cultivation Humus

 What’s left over after organic matter decomposes  Cannot be seen by naked eye  Very reactive (CEC)  In equilibrium with organic matter additions Animal-Based Organic Fertilizers

 By-product of  Manures animal slaughter  Bat guano  Blood meal  Livestock manure  Bone meal  Feather meal  Fish products

Blood Meal 13-1-0.6 (80% protein)

 Bovine blood collected from processing plants, agitated, dried, granulated  Quick N release – ammonia can burn plants Bone Meal 1-13-0 to 4-12-0, + 22% Ca

 Uses  Blooming bulbs (P)  May help prevent blossom-end rot (Ca)  Also useful for root growth of transplants (P)  Bone meal is alkaline, so apply to soils of pH < 7  Need acidic soil to convert to plant-available P Feather Meal Usually 12-0-0

 Made from feathers of slaughtered poultry by hydrolyzing under high heat and pressure and then grinding  Slow release of plant-available N Fish Products

 Many forms, have some P, K, & micronutrients  Fish emulsion, liquid fish (4-5% N)  Derived from fermented remains of fish  Has a fishy smell  Hydrolyzed fish powder (11% N)  Mixed with water and sprayed on plants  Fish meal (powder) (10% N)  Applied to soil Bat/Seabird Guano

 Poop from bats and seabirds – Islands in Pacific & other oceans  From caves – loss of bats & biodiversity  Bat guano: 3-10% N, up to 12% P, 1% K  Seabird guano: Up to 12% N & P, 0-2% K  More expensive than land-animal manures Manures Characteristics and Uses

 Poultry, dairy, feedlot, steer, rabbit, sheep/goat  May contain salts that harm plant growth, and weed seeds  Poultry may have >3%N (ammonia smell)  Aged feedlot manure may have <1% N

Nutrient Content of Manures & Composts Org. Soil Amendments & Fertilizers, 1992

N P205 K20 Fresh broiler / rice hulls 3.9 2.6 2.7 Fresh layer 4.0 6.3 3.4 Aged layer 2.2 8.2 4.0 Fresh dairy corral 2.4 1.3 7.1 Aged steer corral 1.3 1.6 3.3 Broiler / rice hulls compost 1.9 4.3 2.5 Dairy compost 1.4 1.4 2.9 Dairy / steer compost 1.7 0.8 2.6

Compost Characteristics and Uses

 Contains most nutrients required by plants  May contain weeds & plant pathogens  N content usually about 1-1.5%, very slow release  Considered a soil amendment, not fertilizer

Available N from Manures, Compost Decay Series

 UC research, 1970s  Average plant-available N over 3 years (years 1, 2, and 3):  Chicken (90%, 10%, 5%)  Dairy (75%, 15%, 10%)  Feedlot (35%, 15%, 10%)  Compost (~10% in year 1)

Plant-Based Organic Fertilizers

 Alfalfa meal  Cottonseed meal  Soybean based  Kelp/seaweed  Humic acid and humate products Alfalfa Meal (About 2-1-2)

 From alfalfa plants, pressed into pellets  Also contains micronutrients  Especially good for roses, also vegetables  Fairly quick N release Cottonseed Meal (About 6-2-1)

 Derived from the seed in cotton bolls  Some people have concerns about heavy use on cotton and remaining in the seed oils, so they choose organic  Very slow N release Kelp/Seaweed

 Derived from sea plants off Norway, N. Calif.  Available as liquid, powder, or pellet  Applied to the soil or as a foliar spray  Little N-P-K, mainly used for micronutrients, hormones, vitamins, and enzymes  “Can help increase yields, reduce plant stress from drought, and increase frost tolerance” Humic Acid and Humate Products

 Complex organic compounds  Touted to enhance soil microbial life  Enables plants to extract nutrients from soil  Improves soil structure  Enhances root development  Helps plants withstand stresses  May receive same benefits from adding compost Mined Organic Fertilizers

 Rock phosphate  Potassium  Muriate of potash  Sulfate of potash  Greensand Mining of Rock Phosphate

 Source : Natural deposits in N. America, China, Morocco, & former Soviet Union  N. America – Florida, Idaho/Mont./Utah/ Wyoming, N. Carolina, Tennessee Rock Phosphate

 Hard-rock phosphate  20% P and 48% Ca – can raise pH  Breaks down very slowly  Soft-rock phosphate  16% P and 19% Ca, many micronutrients  Form that plants can use more easily  Breaks down very slowly Mining of Potassium Fertilizers

 World reserves deposited when water from ancient inland oceans evaporated  K salts crystallized into beds of potash ore  Covered by thousands of feet of soil

 Most deposits chloride (KCl), some sulfate (K2SO4)  From Canada (#1), Russia, Belarus, US (#7)  New Mexico, Utah, Canada Potash

 K compounds and K-bearing materials (esp. KCl)

 Historically – KCO3 – Bleaching textiles, making glass, making soap (lye)  Made by leaching ashes and evaporating the solution in large iron pots, leaving a white residue called "pot ash“  Term later used for K fertilizer  KCl = Muriate of potash

 KSO4 = Sulfate of potash

Potash Banding

 K attaches to soil particles  K concentrated, so extra K leaches down

 Broadcasting K (or P) on ground has little effect – nutrients are locked up in top 1-2” of soil  Must be banded or incorporated

Topics to be Covered

 Cation Exchange Capacity  Plant Nutrients  Fertilizers  Fertilizing Specific Plant Types  Organic Matter and Organic Fertilizers  Synthetic vs. Organic Fertilizers Chemical (Inorganic) Fertilizers

 No C-H linkage, so not used as energy source by soil microbes  Most are quick-release  Because of the lack of carbon, fertilizers “feed the plant but not the soil.” Chemical vs. Organic Fertilization

 Plants take up nutrients from organic and chemical sources (no preference)  Organic fertilizers feed soil microbes and require them for breakdown (“Feed the soil”)  Microbes (and roots) release compounds like organic acids, enzymes, and chelates  convert nutrients from organic form into a plant-available (soluble) form Advantages of Chemical Fertilizers

 Nutrients available to plants immediately  Produce exact ratio of nutrients desired  Ratios and chemical sources easy to understand  Inexpensive

Disadvantages of Chemical Fertilizers

 Made from nonrenewable sources (fossil fuels)  May not promote soil health  No decaying matter for improving soil structure  Most do not replace micronutrients  Nutrients readily available  chance of overfert.  Tend to leach faster than organic  Long-term use can change soil pH, harm soil microbes, increase pests Advantages of Organic Fertilizers

 May also improve soil structure  Most are slow-release; not easy to overfertilize  Renewable and biodegradable  Can make your own from waste (compost, worm castings) or obtain locally (manure)

Disadvantages of Organic Fertilizers

 May not release nutrients as they are needed  Nutrient content of manure & compost often unknown  % nutrients usually lower than chemical fertilizers  Tend to be bulkier, requiring more fossil fuels; more expensive How Does Fertilizer N Affect Soil Organisms?

 Synthetic fertilizers are salts (not sodium chloride). Salts affect microorganisms, but at what quantities?  Some fertilizers lower pH, hurts some earthworm species, maybe some microorgs. How Much Does it Cost?

 2-lb. box with 12% nitrogen = ?

 2-lb. box with 12% nitrogen = 0.24 lbs. N

 $6 a box / 0.24 lb. N = ?

 $6 a box / 0.24 lb. N = $25.00/lb. N

Nutrient Costs of Selected Fertilizers Local Nurseries, Jan. 2011 $/Lb. of N-P-K Product Analysis (3-5 lb. bag/box) CHEMICAL Azalea/Camellia 4-8-5 $6.46 Rose 5-10-5 $5.49 Mult-Purpose 16-16-16 $2.29 Citrus 12-8-4 $4.58 “NATURAL” BRAND Azalea/Camellia 4-5-4 $17.31 Rose 5-7-2 $16.07 Mult-Purpose 4-4-4 $18.75 Citrus 7-3-3 $11.25 Nutrient Costs of Selected Fertilizers Local Nursery vs. Peaceful Valley Farm Supply Product Analysis $/Lb. N-P-K LOCAL (3.0 to 3.5 lb.) Alfalfa meal 4-8-5 $40.00 Blood meal 13-0-0 $16.81 Cottonseed meal 5-2-1 $21.43 Bat guano (1.5 lb.) 10-3-1 $38.10 PVFS (50 lb.) Alfalfa meal 2.4-0-0 $18.33 Blood meal 13-0-0 $9.23 Cottonseed meal 6-2.5-1 $7.37 Bat guano (25 lb.) 10-6-2 $16.66 Nutri-Rich 4-3-3 $2.80 Organic Fertilization of FOHC Garden Early Years Fertilization of FOHC Garden Currently

Pelleted composted chicken manure Cover Crop + Compost Questions? https://cesacramento.ucanr.edu