organic gardening - american college of healthcare...

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1 www.SherwoodLavender.com www.achs.edu

Organic Gardening

Erika Yigzaw B.Com, LL.B (Hons), Master Gardener


DIY?

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No! GIY!


What does the term “Organic Gardening” Mean to you?

Natural (what does that mean?)

Pesticide free (not necessarily?)

Respects natural patterns?

Remember that organic chemistry does not = organic

agriculture!

Question?

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Between the National Organic Program (NOP) run by the US

Department of Agriculture and the term as used in home

gardening….

Organic Agriculture Federally Defined USDA National Organic

Standards Board 1995: “Organic agriculture is an ecological

production management system that promotes and

enhances biodiversity, biological cycles and soil biological

activity. It is based on minimal use of off-farm inputs and on

management practices that restore, maintain and enhance

ecological harmony.”

Distinguish


Farming that mimics natural ecosystems and maintains and

replenishes the fertility of the soil.

No use of synthetic chemical pesticides and fertilizers

Organic Foods –Grown and handled according to NOP standards

–Minimally processed to maintain the integrity of the food without artificial preservatives or irradiation

Based on ecological principles –Ecology: Nature’s household • Study of the environment and the relations of organisms to each

other and their surrounding "An organic farm, properly speaking, is

not one that uses certain methods and substances and avoids others; it is a farm whose structure is formed in imitation of the

structure of a natural system that has the integrity, the independence and the benign dependence of an organism"

—Wendell Berry, "The Gift of Good Land"

Organic Agriculture

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Use of synthetic chemicals tied to history of chemicals and

genetics in agriculture – put us on a chemical treadmill with

high inputs (energy, water, fertilizer) and expectations (green

lawn in middle of summer, no insects)

Home gardening: Relates to source of products used and

how they are derived

NOP program defines organic extensively, but there is still

confusion

My emphasis is on Low Input Organic Gardening – not just

replacing synthetics with organic alternatives (although that

is a good start!) but by building the ecosystem in your

garden to a self sustaining level…

Organic Home Gardening


Synthetic

Faster but non specific (kills everything, victims may develop resistance, unintended

victims)

Easily available (but now, so are organic alternatives)

Use by Home Gardeners:

http://www.ext.vt.edu/pubs/plantdiseasefs

/450-725/450-725.html: 100 million pounds –71 million pounds herbicide –17 million pounds insecticide/miticide –12 million pounds

fungicides. Does Not include use by landscape companies)

Health risks, risks to wildlife (leaches into waterways), cost, energy … huge implications for sustainability…

Why Go Organic?

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Self education required for organic – requires a different

mindset and aesthetic – e.g. a green lawn has been a sign of

prosperity for centuries, its tough to let it go brown mid

summer!

In 2005 5% of households used organic methods only, 31%

used hybrids – these numbers are expected to double

(National Gardening Association. (2005). Environmental Lawn and

Garden Survey. South Burlington: National Gardening Association.

Retrieved May 12, 2008 at http://www.gardenresearch.com/index.php?q=show&id=2896.)

Organic agriculture movement started in 1940s with Rodale. Rachel Carson’s Silent Spring in 1962 highlighted pesticide damage,

Organic Food Organic Foods Production Act, Farm Bill 1990 -uniform

national standards National Organic Standards 2002 -standards adopted for “organic" labeling

US Gardening is Going Organic…


Ecology •Study of the environment and the relations of

organisms to each other and their surrounding

Ecosystems •Collection of interacting organisms and non

-biotic components in the physical environment

Look at the ecosystem in your garden…

Key Concepts:

•Soil Building

•Conservation

•Biological Pest Management

Ecological Approach

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What is Tilth?

Tilth • the state of aggregation of a soil especially in relation to its

suitability for crop growth –http://www.m-w.com/dictionary

Our job as gardeners is to maintain and enhance tilth in soil through

addition of composted organic material (balanced) and regimented care

Very important to avoid COMPACTION, which prevents air getting to plant roots.

Soil Building and Tilth


See http://soils.usda.gov/SQI/concepts/soil_biology/soil_food_web.html

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What is Soil?

Source: http://www.hort.purdue.edu/


Provide food for soil biology

Feed the soil with organic matter, which:

•Provides long term fertility

•Improves quality of most soils

•Breaks down to form humus (natural glue)

•Strengthens aggregates

•Improves water holding capacity

•Releases plant nutrients

•Provides food for beneficial organisms

•“Feed plants by feeding the soil”

How Do We Build Soil?

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Low C/N ratio, high nutrient value:

raw manure, blood meal, feather meal, less

contribution to organic matter, use sparingly,

do not exceed N and P requirements

Medium C/N ratio, lower nutrient value:

compost, leaf mulch and cover crops, add in

large quantities

High C/N ratio, can immobilize N:

straw, bark & sawdust

What is “Organic Matter”?


Plants need food to grow. The Sun provides energy through

photosynthesis. But plants also need:

• Macronutrients (Large amounts):

Nitrogen, phosphorous, potassium, calcium, magnesium, sulfur •

• Micronutrients (small amounts)

Boron, manganese, zinc

Law of the Minimum

Whatever nutrient is in short supply will limit

growth

Soil test… nitrogen an issue in OR because of rain levels….

Fertilizer?

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Nitrogen cycle important to understand. Atmosphere contains 78%

N but it is unavailable to plants. Some plants e.g. rhizomes (peas etc) fix atmospheric nitrogen.

Always must provide nitrogen sources:

•Previous compost and manure applications

•Crop residues

•Cover crops (legumes fix nitrogen, grasses reduce losses)

•Soil organic matter (0.23# -0.69# / 1000 sq. ft. for each 1% organic

matter)

•Supplemental fertilizers (i.e.. blood, feather, corn, fish meal)

Organic nitrogen sources do accumulate, but still add new each

year

Nitrogen: How to Get It


The following use up or leach nitrogen from the soil. Avoid

unnecessary reductions in your garden’s nitrogen

Rain and over-irrigation = leaching. Always water just

enough. Use drip irrigation rather than overhead watering.

Cultivation: avoid tilling, no till or raised beds retain more

nitrogen

Evaporation –incorporate amendments, mulch to reduce

Crop removal –incorporate residues through compost,

digging in residues

Goal = Minimize leaks in the nitrogen bucket

Nitrogen: How to Keep It

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Soil organisms break down the remains of plants and other

organisms.

This process releases energy, nutrients, and carbon dioxide,

and creates soil organic matter.

Organic gardening keeps soil organisms at optimal levels.

Monocultures, synthetic fertilizers and pesticides destroy soil

organisms.

Soil Organisms


Cover Crops

Compost

Deep cultivation

Fertilizing

Weed control

Mulch

Organic Fungicides

Organic Herbicides

Organic Gardening Methods

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•Reduce erosion

•Protect soil structure

•Fix Nitrogen and improve nutrient

availability

•Supply N without increasing soil P

•Reduce nitrate leaching

•Increase soil organic matter

•Improve mycorrhizal winter

survival

•Reduce weed pressure

•Provide nectar & pollen for

beneficial insects

Cover Crops


Compost meets many needs in

the garden:

- Improves soil structure by

adding organic matter

- Conserves nitrogen

- Feeds soil microorganisms

- Provides macro and some

micronutrients

- Saves money

Compost

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Can be easy or complicated. Few gardeners could make enough to meet all needs. Add 2 inches per crop season.

Easy:

Make a pile of organic materials – pruned branches, weeds (without seeds), leaves, manures. Leave it for approx 1 year. Use the compost that is

underneath.

A bit more work:

Put the same organic materials into some kind of bin and turn every month or so

Easier but more expensive:

Put materials into a compost tumbler

Make Your Own Compost


See videos at www.youtube.com/achstv

Make Your Own Compost

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Double digging –Broad fork

–Raised beds

For landscapes-mix composted

organic material 18”deep

–Mechanical digger

Deep Cultivation


USDA List of Approved Fertilizers

Always check cost ratio – some are very expensive for NPK

levels

Organic Fertilizers (OSU Master Gardener Materials) Material % N % P % K

Fertilizing

•Cotton seed meal 6-7 2 1

•Blood meal 12-15 1 1

•Alfalfa 2 0.5 2

•Bat guano 10 3 1

•Fish meal 10 4 0

•Fish emulsion 10 4 0

•Bone meal 1-4 12-24 0

•Rock phosphate 0 25-30 0

•Greensand 0 0 3-7

•Kelp meal 1 .1 2-5

•Organic fertilizer calculator at http://smallfarms.oregonstate.edu

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Old fashioned weeding is the cheapest and most effective

method: Weed after watering or rain, don’t let weeds set

seed (up to 100k seeds that can last 100 years!), hoe in hot

weather and weeds will die, hoe when weeds are small.

Other methods:

Weed Control

•Plant transplants so they have

a head start on weeds

• Use Cover crops

• Crop rotation

• Avoid bringing new weeds to

the garden in manure, straw

•Stale seedbed

•Collect edible weeds

•Use weeds in compost (not

once seeded)

•Plant closely together


Landscape fabric

• Plastic mulch –Black plastic

–Purchase, disposal &

irrigation

• Straw mulch –Weed seeds

–Irrigation & nitrogen

• Sheet Mulch –Newspaper

/cardboard

Mulch

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Cut existing material to ground –Add nutrients –Water –Thick

newspaper –Thick mulch

Don’t try with perennial weeds

Sheet Mulch


Vinegar (acetic acid)

Clove/citric acid based

Herbicidal Soap: Contact herbicide and is non-selective. OK

for annuals but not very effective for perennials

Corn gluten: Pre-emergent (i.e. supposed to stop weed seeds

germinating) Not effective – Good N fertilizer

Organic Herbicides

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1. Plough or spade

2. Prepare seedbed

3. Irrigation or rain then wait 1-2 weeks

4. Flame, vinegar or herbicides, or very light cultivation

5. Repeat if possible

6. Plant or sow seed

Stale Seedbed Method


Are organic alternatives to synthetic insecticides

Can still be toxic, so still take precautions when using

Other alternatives are to diversify plantings, use right plant for

right place, choose adapted varieties, choose resistant

varieties, build the soil (cover crops, compost, don’t cultivate

when too wet or dry), water correctly (adequate, in morning,

drip not overhead to avoid spreading fungal diseases), feed

adequately (compost or organic fertilizer), plants and

habitats for beneficial insects, plant to allow some airflow,

tolerate some damage, hand pick insects, rotate crops, use

chickens!

Healthy plants resists pests and recover quickly & healthy

landscapes prevent pest outbreaks

Managing Pests

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Principles of IPM

• Prevention

• Monitor the plants

• Identify the pest organism –learn

life cycle (e.g. codling moth

larvae emerge in March/April)

• Establish an acceptable injury

level

• Manage the situation –Cultural

–Biological –Chemical (organic

and synthesized)

• Evaluation

Integrated Pest Management


Horticultural oils • Copper based • Sulfur • Serenade (Bacillus

subtilus) • Baking soda (K) This is a peach tree grafted with

two curl resistant cultivars. Cultivar 'Q 1-8' on the left and the

cultivar 'Mary Jane' (with lots of curl) on the right.

See Materials Allowed for Organic Disease Management at

http://ipmnet.org/plant-disease/articles.cfm?article_id=44

Organic Fungicides

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• Azadirachtin-Neem • Bt-biological • Beauveria-biological

• Horticultural oils • Insecticidal soap • Iron phosphate-slugs

• Kaolin clay • Lime Sulfur • Pyrethrins • Rotenone •

Spinosad-biological • Sulfur

With All Products • Label is the law • Identify plant and pest

and confirm on label for allowed uses of products • Read

and follow the directions! • Wear proper eye protection,

mask, clothing, gloves, etc.

Organic Pesticides


Diverse plantings encourage beneficial

insects

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Choose the right plants – ones you like and ones that like

your climate

Take care of your soil – don’t plant directly into unworked

ground, add lots of compost, befriend someone with a

horse…

Allow for a diverse range of plantings – mix flowers and herbs

in with your vegetables

Don’t plant things when its too cold out

Don’t work the soil when its too cold and wet

Have a sense of humor –

Keys to Successful Organic Gardening


Hardiness

Different species and varieties have varying hardiness and

each requires different treatment. Find out your zone and

choose plants that grow in that zone.

Choose the right plants

This January 2008 snow falls

on our one year old plants

tested their hardiness. We will see how many plants

were affected once the

plants put on their new

growth.

Photograph by Erika Yigzaw

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Attract beneficial insects

Lavender is one of many plants that attracts many beneficial

insects, including bees, hoverflies, and butterflies.

In fact, bee keepers love putting their hives at lavender farms, as the

lavender honey is delicious!

Bees on lavandin at the ACHS

garden in John’s Landing.


It is great fun to grow your own food organically

Get kids and spouses involved – even the most hardened heart

warms when picking the first spring peas!

Gardens can be easy to

look after Grow what you like to eat. Don’t

waste time growing things that your

family wont eat anyway.

Weed regularly, right after watering,

and before weeds go to seed.

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Helpful Links

Photographs

by Erika

Yigzaw at Hood River

Lavender

Farm.

Australasian College of Health Sciences www.achs.edu

Apothecary Shoppe www.apothecary-shoppe.com

Erika’s blog: http://confessionsofamastergardener.blogspot.com/

Oregon Master Gardener Program http://extension.oregonstate.edu/mg/

Find the last frost date in your area and estimated times to plant based on your zip code from the Farmer’s Almanac

http://www.almanac.com/garden/plantingtable

/index.php

Master Gardener Hotline for any questions: 503 725 2300

Metro Events (including Gardens of Natural Delights):

http://www.oregonmetro.gov/index.cfm/go/by.web/id=576

Tour De Coops:

http://growing-gardens.org/portland-gardening-resources/chickens.php


Essential Oil Production:

This microscope photograph enables you to see the essential oil sac

on the leaf of a lavender plant.

organic gardening - american college of healthcare...

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