2015 MG Fertilizers1
Soils
Claudia Groth
Master Gardener Program Instructor
2015 Master Gardener Training
Deserts, swamps, mountains, N/S poles
Too hot
Too wet
Too rocky
Oceans
Can be developed Available
soil Our Soil Where do soils come from?
• Parent material
• Climate
• Topography
• Living things
• Time
Soil Profile
1998 Michael Hofmockel
PNW Soil
Groups
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Physics
Chemistry Biology
Soil
Soil Components
(CA Fertilizer Association)
Soil Texture
How coarse or fine a soil is
The proportion of sand, silt, and clay
The arrangement of sand, silt, and clay
Soil Structure
Relative Sizes of Soil Particles
(University of Nebraska, Lincoln)
Soil Triangle
% Clay % Silt
% Sand
Soil Texture
Sandy
Clay-like
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Particle Size and Surface Area
volume = 64
surface area = 384
volume = 64
surface area = 96
4 1
Water-holding Capacity of Different Soils
(inches of water per foot depth of soil)
Sandy soil = .75 to 1 inches/ft
Loam soil = 1.5 to 1.75 inches/ft
Clay soil = 2.0 to 2.5 inches/ft
Soil Texture and Water
(Adapted from Cooney and Peterson, 1955)
Water Movement in Soils
sandy loam
clay loam
Impacts of Texture
Water-holding capacity high low
Drainage and permeability slow fast
Spring warming slow fast
Crusts and packs, restricts root growth yes no
Nutrient-holding capacity high low
Clay-like Sandy
Determining Soil Texture
• Soil surveys (Web Soil Survey) – Silt loam predominates in Metro area
• Professional soil test – Laboratory analysis ~ $16 (w/o nutrient test)*
• Ribbon test – Messy, but interesting
• Home jar test or “shake method” – Pretty accurate – easy and fun
*EM 8677 Laboratories Serving Oregon: Soil, Water, Plant Tissue, and Feed Analysis
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Soil Survey – St. Helens
45
19E
69
1A
14D 45
19E
69
1A
14D
Silt loams
Rocky Shallow to bedrock
Determining Soil Texture
• Soil surveys (Web Soil Survey) – Silt loam predominates in Metro area
• Professional soil test – Laboratory analysis ~ $16 (w/o nutrient test)*
• Ribbon test – Messy, but interesting
• Home jar test or “shake method” – Pretty accurate – easy and fun
*EM 8677 Laboratories Serving Oregon: Soil, Water, Plant Tissue, and Feed Analysis
Taking a Soil Sample Soil Test Results
Ribbon Method sand
silt
clay
Texture via “Soil Shake”
• 1/3 to 1/2 soil
• Fill with water
• Shake 5 minutes
• Measure
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Mark/Measure Each Depth
• Sand:
40 seconds
• Silt:
30 minutes
• Clay:
24 hours
Soil Textures in Jar Test
Calculate % of Each Particle
The math:
Height of the layer
Height of all layers
e.g.: (0.5 / 2.00) X 100 = 25%
X 100
Using the
Soil Triangle
Sand: 40%
Silt: 40%
Clay: 20%
Loam
40% sand
40% silt
20% clay
Using the
Soil Triangle
Sand: 33%
Silt: 33%
Clay: 33%
Clay Loam
33% sand
33% silt
33% clay
Just Add Sand??
particle in. percent Sand 2.2 20% Silt 6.6 60% Clay 2.2 20% 11.0
10’ x 10’ = 100 sq ft.
particle in. percent Sand 3.2 27% Silt 6.6 55% Clay 2.2 18% 12.0
Add 1 in. sand (830 lbs.)
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Guideline for Using Sand
If you mix sand into clay,
mix in 30% by volume of coarse sand
• Mix in 2 inches of organic matter
• Mix in 3 inches of sand
• Mix in 2 inches of organic matter
What About Gypsum?
Calcium Sulfate
Gypsum won’t improve drainage
in Pacific NW clay-based soils
Gypsum doesn’t change soil pH
We Can’t Change Soil Texture
But that’s not the end of the story
Changing Soil Structure
Soil Structure Aggregation
• Increases aggregation of particles – Reduces wind and water erosion
– Increases infiltration of surface water
• Increases drainage (clay soils)
• Increases water-holding (sandy soils) – Reduces water losses through soil
• Increases nutrient-holding – Improves nutrient availability
– Reduces leaching losses
Add Organic Matter!
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Soil Habitat
S. Rose and E.T. Elliott
In One Gram of Soil – ¼ tsp.
• Bacteria 100 million – 1 billion
• Actinobacteria 10 million – 100 million
• Fungi 100,000 – 1 million
• Algae 10,000 – 100,000
• Protozoa 10,000 – 100,000
• Nematodes 10 - 100
Soil Organism Diversity
• Changes with – Soil type
– Soil management methods
– Crops grown
• Impacts disease organisms – Suppression
• Difficult to study and characterize – Culture vs DNA methods vs ???
Mycorrhizae3
Actinobacteria1
Rhizobia2
1No. 14 from Soil Microbiology and Biochemistry Slide Set. 1976. J.P. Martin, et al., eds. SSSA, Madison, WI 2Stephen Temple, New Mexico State University 3Mycorrhizal Applications, Inc., Grants Pass, Oregon
• Plant Roots • Archea • Bacteria • Fungi • Algae • Protozoa • Nematodes • Insects • Earthworms • Vertebrates
Exudates Enzymes Hyphae Organic acids
Nutrients Glomalin Humus
Biology Helps Create Structure Improving Soil Structure
Fine Soil
Coarse Soil
Well-aggregated Soil
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Functions of Soil Biology
• Water uptake
• Worms/microarthopods grind up organic matter
• Microbes decompose organic matter to humus
• Cycling nutrients – Changing forms of nutrients
– Fix nitrogen
– Control nutrient quantity/availability
• Degrade chemicals
• Disease control
Organic Matter Amendments (soil conditioners)
• Composts – Garden waste/manure/mushroom/etc.
• Manures – Fresh/composted
• Cover crops (green manure)
• Sphagnum peat moss
• Grass clippings
• Biosolids
• Coir
• Straw
One Year Later . . .
What’s happened to your compost?
CO2
Soil-living critters
Non-humic compounds
Humus
One Good Strategy
• Annuals/Vegetables – The first time you prepare the soil
• Mix in 4 inches organic matter
– Each planting season • Mix in 2 inches more
• Perennials/Shrubs – Maintain 1 to 3 inches organic mulch
Inorganic Amendments (also soil conditioners)
• Hardened clay and diatomaceous earth – Turface/Profile
– Amturf Ultra Soil Conditioner
– AXIS
• Gravel – Quarter-ten (1/4 -10)
• “sand” – you know how I feel about this
Beware These Materials • Bark dust/sawdust/wood chips
– unless you also add nitrogen
• Perlite or vermiculite – Potting mix/Planter mix
• Top soil – Source???
• Cat litter • Sand • Biochar
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Now you know “what” – How?? • Tilling
• Hand digging
• Lasagna or layering
• Broadfork
And when?? • Spring • Summer • Fall
Broadfork
Soil and Air Spaces Compaction Destroys Structure
•Beware foot and equipment traffic
•Don’t dig in soggy soil
•Establish permanent paths
•Protect surface
•Avoid excessive tilling
Change in Structure = Interface
Layering impedes water movement
and root growth
Judging Compaction
• Hard
• Average
• Easy
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Drainage - Infiltration
How fast water goes into the soil
• Push a can into the soil
• Mark a line 1 inch above the soil and another at 2 inches above the soil
• Fill the can to the 2-inch line
• Record the water level several times over an hour
• Calculate the number of inches per hour
2 to 8 inches is good
less than 0.4 inches/hour is quite slow
Drainage - Percolation
How fast water drains out of the soil
• Dig a 12” by 12” wide/deep hole
• Fill with water and allow it to drain out
• And, again. Soil should be thoroughly wet
• Fill again with water; mark
• Measure depth after 15 minutes
(x 4 = inches of outflow/hour)
4 to 8 inches per hour is good
Prevent Compaction with Permanent Paths
University of Maryland Extension
University of Missouri Extension
Ways to Improve Drainage
• Use raised beds
• Install drain lines
• Install a berm (mound)
Drainage in Raised Beds with sides
Saturation zone Saturation zone
Premium Soil Mix
Native soil
Organic Mulches
Adding organic matter without digging
• Food for many soil dwellers
• Form aggregates during decomposition
• Plus: – Maintain soil temperature for microbe activity
– Aid in water penetration (less run-off erosion)
– Conserve moisture by reducing evaporation
– Add (small amounts of) nutrients to the soil
– Minimize compaction
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Soil Texture Soil
Structure Soil
Profile
1998 Michael Hofmockel
Know your soil - make it work for your garden!
Resources • Oregon State Extension Service publications:
– Improving Garden Soils with Organic Matter (EC 1561) – Mulching Woody Ornamentals with Organic Materials (EC 1629)
• Web Soil Survey – google: web soil survey
• Soil Biology Primer – Soil and Water Conservation Society www.swcs.org or
google: soil biology primer
• Books – The Soul of Soil: A Soil-Building Guide for Master Gardeners
and Farmers (4th edition) by Grace Gershuny – Elements of the Nature and Properties of Soils (3rd Edition) by Nyle C. Brady and Ray R. Weil
Container Soils
Natural vs. Container Soils
Solids (incl org mat)
Air
Water
Organic Matter
Water
Solids
Air
Soil Compaction in Containers
Compressed Soil
18 inches
Water Movement in Containers
Soil
Saturated zone
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Here’s what happens
Actual soil volume for plant roots is reduced
Impact of pot size on re-potting
Soil:Container Relationship
Greenhouse container
Color bowl Seedling tray
Soils
Claudia Groth
Master Gardener Program Instructor
2014 Master Gardener Training
Fertilizers
Claudia Groth Master Gardener Program Instructor
2015 MG Fertilizers13
Why Do We Feed Plants,
Anyway? Essential Elements
• From air and water carbon (C) hydrogen (H) oxygen (O)
• Macroelements nitrogen (N) phosphorus (P) potassium (K)
• Secondary elements sulfur (S) calcium (Ca) magnesium (Mg)
• Micronutrients boron (B) chlorine (Cl) copper (Cu) iron (Fe) manganese (Mn) molybdenum (Mo) zinc (Zn)
Essential for Growth Nutrient Deficiency
Iron Deficient
Phosphorus Deficient Ph
oto:
Ala
ndm
anso
n PD
Phot
o: F
rank
Vin
cent
z C
CA
-SA
3.0
Nutrients, Roots, and Soil
_ _
_
_
_
_
_
_
_ _
_
Ca++
Mg++
K+
H+
Organic
Matter
Particle
Most local soils - high CEC (>10 meq/100g)
Any CEC value is not good or bad • Affects lime/fertilizer needed • Used in soil test recommendations
CEC is low in very sandy soils • Poor capacity to hold nutrients • Added fertilizer nutrients leach easily • Multiple small applications • Slow release fertilizers
Cation Exchange Capacity
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Influencing Nutrient Availability
• Soil texture
• Amount of organic matter
• Competition/impact of other nutrients – taking up all the space on soil particles
– forming insoluble compounds
• Microbes alter the form of nutrients
• Temperature of soil
• Acidity of soil
Why does pH matter?
Acid? Alkaline? Neutral?
(CA Fertilizer Assoc)
Soil pH and Nutrient Availability pH is measured in log scale
What does “log scale” mean ?
100 times increase in acidity
10 times increase
pH=6 pH=5
pH=4
Changing Soil pH
• Raising pH – Lime (max. 5 lb. per 100 sq.ft.)
– Wood ashes ( 1.5 lb. per 100 sq.ft. per year)
• Lowering pH – Ammonium sulfate
– Sulfur-coated urea
– Aluminum sulfate
– Sulfur (max. 5 lb. per 100 sq.ft.)
Ensuring Plant Nutrition • What’s there already?
– Soil testing
• Conserve what we have – Optimum pH (keeps nutrients in available form) – Reduce erosion (nutrients leave with soil) – Reduce leaching (nutrients move below roots) – Recycle them (composting and mulching)
• Add nutrients – Packaged – organic material - cover crops
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Taking a Soil Sample Soil Testing
Soil Test Results Ensuring Plant Nutrition • What’s there already?
– Soil testing
• Conserve what we have – Reduce erosion (nutrients leave with soil) – Reduce leaching (nutrients move below roots) – Recycle them (composting and mulching) – Optimum pH (keeps nutrients in available form)
• Adding what we need – Packaged – organic material – cover crops
The Phosphorus Issue
Excess phosphorus degrades waterways
• Limit the use of phosphorus fertilizers – Soil testing
• Minimize water runoff – Reduce erosion
– Increase cover
– Improve irrigation efficiency
Ensuring Plant Nutrition • What’s there already?
– Soil testing
• Conserve what we have – Reduce erosion (nutrients leave with soil) – Reduce leaching (nutrients move below roots) – Recycle them (composting and mulching) – Optimum pH (keeps nutrients in available form)
• Adding what we need – Packaged – organic material – cover crops
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What’s it all mean?
• Rose and flower foods – 9-18-9, 18-24-16, 4-6-2
• African violet foods – 8-14-9, 7-7-7
• Japanese maple fertilizer – 4-8-5
• Citrus and fruit tree food – 7-3-3
• Orchid foods – 30-10-10, 19-31-17, 20-20-20, 3-12-6, 7-9-5
Reading the Label
• The analysis is the percentage of N-P-K
• In this package, the analysis is 12-12-12
• The ratio is 1-1-1
Analysis versus Ratio
The analysis is
21-7-14
The ratio is
3-1-2*
*OSU recommended lawn food ratio
Choosing a Fertilizer
What are you using it on?
• Ornamental trees – lower requirement – Wide-ranging root system – Not an intensive crop
• Vegetable garden – higher requirement – Maximum crop desired – Short season of growth
Natural – Organic – Synthetic
What does it really mean?
– Consumers
– State fertilizer regulations
– US Department of Agriculture
– Environmental Protection Agency
– Private certifying agencies
Humic acids Amino acids Environmentally-friendly
And what about . . .
Probiotic Vitamins
Balanced Complete Healthy Enhanced
Added Microbes • Mycorrhizae
• Bacteria
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Fertilizer Side Panel
Total Nitrogen (N) …………………………………… 5.0% 2.0% Ammoniacal Nitrogen 0.6% Water Soluble Nitrogen 2.4% Water Insoluble Nitrogen Available Phosphate (P2O5) ….…………………… 8.0% Soluble Potash (K2O) …………….………………… 4.0% Derived from: dried poultry waste; alfalfa meal;
ammonium sulfate; ammonium phosphate; sulfate of potash magnesia; calcium and sodium borate; ferrous, manganese, and zinc oxides; sodium molybdate.
Choices, choices, choices
Choose by form of nutrients S l o w – r e l e a s e vs.
Choose by source of nutrients
Synthetic
vs.
Natural
»» Fast-acting
Sources • Ammonium sulfate • Ammonium phosphate • Urea • Some naturals - Bat guano - Blood meal - Fish meal
Fast-acting • Water soluble nitrogen • Other water soluble nitrogen • Water soluble organic nitrogen • Ammoniacal nitrogen • Urea nitrogen • Nitrate nitrogen
Long-lasting • Water insoluble organic nitrogen
• Water insoluble nitrogen
• Sulfur-coated urea
• Polymer-coated urea
• Coated slow release
Sources • Ureaformaldehyde
• Methylene urea
• Nitroform
• Most naturals, such as:
dried poultry waste
alfalfa meal
blood meal
Reading the Label Total Nitrogen (N)………………………………… 7.0% 5.92% Water Insoluble Nitrogen 1.08% Water Soluble Organic Nitrogen Available Phosphate (P2O5)………………… 7.0% Soluble Potash (K2O)…………………………… 2.0% Calcium (Ca)…………………………………………… 7.0%
Derived from: Fish meal, fish bone meal, sunflower hull ash, alfalfa meal, feather meal, and blood meal.
85% slow-release nitrogen
all-natural
Reading the Label
Total Nitrogen (N)……………………………. 5.0% 0.50% Ammoniacal Nitrogen 3.75% Other Water Soluble Nitrogen 0.75% Water Insoluble Nitrogen Available Phosphate (P2O5)………….. 1.0% Soluble Potash (K2O)………………………. 1.0% Derived from: Seagoing Fish Emulsion.
85% quick-release nitrogen
all-natural
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Reading the Label
Total Nitrogen (N)………………………………. 21.0% 13.2% Ammoniacal Nitrogen 7.8% Urea Nitrogen* Available Phosphate (P2O5)………………… 2.0% Soluble Potash (K2O)…………………………… 4.0% Sulfur (S)………………………………………………… 16.0% Iron (Fe)……………………………………………………1.0% *5.2% Slowly available urea nitrogen from sulfur-
coated urea Derived from: Ammonium Sulfate, Urea, Sulfur-
Coated Urea, Ammonium Phosphate, Muriate of Potash, Ferrous Sulfate.
Let’s look at some of those ingredients?
Synthetic Nitrogen Sources
• Ammonium sulfate
• Urea
• Ureaformaldehyde
• Coated ureas
• Coated slow release
Osmocote™
Polymer coating
Urea
Urea
Sealer
Sulfur coating
NH2 H2N
O ( (NH4)2SO4
Bat Guano (10-3-1)
– A source of fast-acting nutrients, particularly nitrogen, for use when quick plant growth is desired.
– Can be used for all types of gardening, even containers.
Bat Guano (3-10-1) – An excellent source of phosphorus
Blood Meal (13-0-0)
– A high nitrogen organic plant food.
– If all you need is nitrogen, use once a year.
– Nitrogen-hungry crops, such as citrus, corn, and lawns, may need another application in mid-season.
**Also effective as a compost activator and as a deer and squirrel repellent.
Alfalfa Meal (2-0.5-2)
– Good general source of nitrogen, phosphorus, and potassium.
– Good carbon-to-nitrogen ratio, which helps speed its availability in the soil.
**Recommended by rosarians for roses, to strengthen cane production and promote blooming.
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Organic Material as Fertilizer
• Low in overall nutrients – Contains many micronutrients
• Long-lasting, gentle-feeding
• Compost – homemade or purchased – Rich smell, uniform texture
• Sawdust, bark dust, pine needles, straw – Can tie up nitrogen, if uncomposted
Animal Manures as Fertilizers
• Added salts
• Weed seeds
• Smell
• Inconsistent
• Unknown analysis
• Availability of nutrients
Synthetics and Organics • Advantages
– Compact
– Tailored
• Disadvantages – Use oil/natural gas
– Mined/processed
• Advantages – Use wastes
– Nutrient-rich
– Add OM to soil
– Feed microbes
• Disadvantages – Bulky
– Mined/crushed
– Weed seeds
– Variable
– Odor
What about cover crops? Vetch supplies:
1.2# plant available nitrogen/1,000 sqft
It’s a crop that needs to be
managed
Tomato crop needs 2.9# N
Lettuce crop needs 2.0# N
smallfarms.oregonstate.edu
Fertilizer Formulations Spikes, tabs and sticks Soluble powders Slow release Dry granules Liquid
Applying Fertilizer
• Broadcast (liquid/dry)
• Incorporate
• Band
• Sidedress
• Foliar
Never fertilize dry soil
Never fertilize dry potting mix
Follow label directions
Dripline
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Application Error Problems with Excess Fertilizer
• Runoff into surface water
• Leaching into groundwater
• Increased insect pests
• Weak growth
• “Burn”
The “Best” Fertilizer
What’s your (or your client’s) objective?
• Food crop – Can they tolerate loss?
• Ornamental – Selling a home
– Neighborly competition
Observe/Ask questions – Then act
Resources OSU/WSU Extension publications:
– Fertilizing Your Garden: Vegetables, Fruits and Ornamentals (EC 1503)
– Fertilizing Shade and Ornamental Trees (FS 103) – Cover Crops for Home Gardens in
Western Washington and Oregon (EB 1824) – Values of Organic Fertilizers (Douglas Cty) (LC 437) – Nutrient Disorders in Tree Fruits (PNW 121-E) – Fertilizing Lawns (LC 1278 )
google: Oregon extension publications
Claudia Groth
Master Gardener Program Instructor
Fertilizers
Composting
2015 MG Fertilizers21
Many Ways to Compost
•Hot pile
•Cold pile
•Trenches
•Sheet (Lasagna)
•Worm bins
•Anerobic
Hot Composting •As fast as 30 days
•Kills weed seeds
•Kills plant diseases
Cold-Pile, No-Fuss Composting
• Food scraps/lighter materials
• Plenty of bulking materials
• Add side/bottom screen
• 9 to 12 months
Earth Machine
Wire Systems
Three-bin System Composting Specs
• 3’ x 3’ x 3’ volume minimum
• 110 to 160 °F – Can loose nitrogen as ammonia
• Cover from rain and sun
• Aeration is critical
• Moist, but not wet
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Surface : Volume Ratio
• Smaller size particles
• Increases rate of decomposition
Raw Materials • Energy Materials “Greens” (High nutrient)
– High moisture, low porosity, high nitrogen
– Grass clippings, cow/rabbit/chicken manure, food waste, garden trimmings
• Bulking Agents “Browns” (High carbon) – Low moisture, high porosity, low nitrogen
– Wood chips, sawdust, grass hay, straw
• Balanced Materials (Nutrient = Carbon) – Low to medium moisture, porosity, and nitrogen
– Tree/shrub trimmings, horse manure/bedding, deciduous leaves, clover/alfalfa hay
~
Avoid
• Meat (and fish) and dairy products – Decompose slowly
– Attract rats, raccoons, other “pests”
– Egg shells okay
• Grease and cooking oil
• Invasive weeds – morning glory, quackgrass
• Diseased plants
• Weed seeds and seed heads
• Dog and cat waste
Manures and Bedding
• Great source of nutrient-rich material
• Cow, horse, goat, rabbit, poultry – okay – Pig - questionable
• May spread plant diseases and weed seeds – Ensure hot composting
• Human Manure – From composting toilets
• Not for food gardens
Composting in the Garden
• Trench
• Post-hole
• Sheet
• Lasagna
Anaerobic Composting • Without oxygen
• Lots of nutrients without carbon source – Food wastes, manures
• May produces odors
Bokashi
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Worm Composting
• Use worms to recycle organic materials (food scraps)
• Complex organic materials converted nutrient rich compost
• Vermicompost, or worm compost
What Worms Need
• Very low maintenance
• Understanding basic needs is key – Bedding
– Moisture
– Air
– Organic materials, food scraps
– Moderate temperature
Worm Bins
• www.oregonmetro.gov • search: OSU extension
publications
Claudia Groth
Master Gardener Program Instructor
Fertilizers
Composting
2015 MG Fertilizers24
Surface charges on humus Binds pesticide residues, pollutants Soil acts as a natural filter, keeps water bodies clean
Soil texture Structure Soil Profile
Know your soil, make it work for your garden and for the environment !
What is Soil pH/Acidity
Improved Soil Structure
Fine Soil Good structure
Coarse Soil Poorly aggregated
Particle size and surface area
2015 MG Fertilizers25
Iron def
• Mg def
Drainage - Percolation
How fast water drains out of the soil
•
• Dig a 12-inch by 12-inch wide deep hole
• Fill with water and allow it to drain out
• Fill with water and allow it to drain out, again. Soil should be thoroughly wet.
• Fill again with water; mark depth on a yardstick
• Measure depth after 15 minutes
• x 4 = inches of outflow per hour
• 4 to 8 inches per hour is good
Drainage - Infiltration
• How fast water goes into the soil
•
• Push a can into the soil
• Mark a line 1 inch above the soil and another at 2 inches above the soil
• Fill the can to the 2-inch line
• Record the water level several times over an hour
• Calculate the number of inches per hour
• 2 to 8 inches is good; less than 0.4 inches per hour is quite slow
