Sustainable Organic Vegetable Gardening

2008 Basic Training for Master Gardener Interns

Jon Traunfeld- jont@umd.edu

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A world of colors and good eating awaits you…

Vegetable gardening: Back to the future

• New wave of interest fueled by– rising food prices– rising energy prices– buy/grow local movement

• Seed sales and media stories on vegetable gardening are way up in 2008

• Backyard and community gardeners are a critical link in any local food system

Master gardener roles• Get more people to grow food.• Work on MG food projects- youth,

community, and demo gardens.• Educate new and veteran gardeners

through classes and workshops; teach basic MG training.

• Diagnose problems and answer questions at plant clinics.

Promote organic/sustainable approach

Increasing food production one vacant lot at time

School gardens rock

Why do people grow vegetables?

• Flavor, freshness, pesticide-free• Health benefits

exercise, nutrition, phytochemicals• Connection to mother earth, family traditions• Introduce youth to gardening• Save money; learn new skills

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What is organic gardening??

• Twin cornerstones:– build soil health (feeding the soil food web and recycling nutrients)– increase biological diversity above and below

ground- plants, insects, microbial life• Organic doesn’t mean simply substituting

purchased organic pesticides and fertilizers for synthetic products

What is a sustainable garden?

• Sustains itself through reliance on inherent resources; mimics natural eco-system.

• Needs a minimum of purchased “inputs” and relies on locally-available materials.

• Does not pollute; strengthens the community eco-system.

• Requires knowledge, planning, and timing.

Maryland’s growing conditions

• Growing season days- 150 to 225.• Four distinct seasons; quick changes in weather.• Wide range of soils- (many urban and suburban soils

are greatly changed from native soils.) A wide range of warm and cool season crops can be

grown (with planning and care.)

Global warming• Stronger storms and persistent drought.• Increasing average temperatures.• Higher CO2 levels- “super weeds.”

• Gardener response: – reduce the use of fossil fuels (gasoline, plastic, fertilizer)– keep soils covered with plants or mulch– conserve water; use drip irrigation– provide afternoon shade for crops; select heat-tolerant

crops and cultivars– opportunity for season extension (spring and fall)

Vegetable crops

• 5-10 plant families may be represented in the average garden (none are native to MD and few are native to North America!)

• Most are annuals with a life cycle somewhere between 25 days (radish, baby greens) to 110 days (big pumpkins.)

• Require good growing conditions to produce high yields.

• Can be incorporated into ornamental landscape.

Ingredients for success

• Good, deep soil.• Adequate nutrients, water and sunlight.• Freedom from weed competition.• Knowledge/planning.• Attention/timing.

Site selection• Level ground; close to water source.• Southern exposure; tallest plants on North

side.• Protection from critters.

Digging and aerating tools

You need “good soil”

• Urban/suburban soils are usually of poor quality• pH- 6.0-6.8 is preferred range.• Friable- deep, crumbly; allows for maximum root

growth.• Regular additions of organic matter will improves soil

structure and water drainage and create a reservoir of slow-release nutrients.

Ways to add organic matter

• Farmyard manure• Compost• Shredded leaves and grass clippings• Organic mulches• Plant roots• Cover crops

• Large amounts of organic matter may be needed for several years.

• Thereafter, 1 in. of compost will help maintain high yields.

Using animal manures

• Should be thoroughly composted or well-decomposed (> 6 months.)

• Till manures under in fall when possible.• Wash all produce thoroughly after harvest.• Never use pet manures in the vegetable

garden.

Cover crops improve and protect soils

• Increase soil organic matter. • Mine the soil for nutrients. • Protect soil from erosion.

Buckwheat Winter wheat/hairy vetch

Crimson clover: adds nitrogen and beauty

• Plant spring/summer– buckwhea

t, white, red, or

crimson clover,

alfalfa, oats

Rhizobium nodules on clover

Pick a cover crop you can handle• Winter wheat and rye grow rapidly in

spring- turning under by hand is hard work.• Oats are winter-killed and easy

to turn under.

Most commonly available commercial organic fertilizers

• Fish emulsion: 6-2-2• Seaweed extract: 1-.5-2• Bloodmeal: 15-1-0• Cottonseed meal: 6-2.5-1.5• Guano: 8 to 13-8-2• Bone meal: 4-21-0• Rock phosphate: 0-22-0• Alfalfa meal: 3-1-2

Organic fertilizing tips

• Nitrogen is nutrient most often in short supply. Use one of the “meals” (kelp, fish, cottonseed, alfalfa) to supplement N from organic matter.

• Follow label directions.• Organic fertilizers can be over-applied and burn

plants or stimulate excessive leaf growth at the expense of fruit.

• Add 1 inch of compost each year to contribute to long-term nutrient reservoir.

Starting a GardenKill sod and control weeds • Cover area with black plastic or cardboard,

leaves, and compost OR• Dig up the area by hand or with a tiller

To till or not to till• Benefits of a roto-tiller:

– great for turning under cover crops, residues, and manure.

– makes soil loose and weed-free for planting.– can disrupt pest populations in the soil.

• Potential problems:– damaged soil structure if you till wet soil.– soil compaction if machine is over-used.– fresh tilled soil is more erodable.– “burns up” organic matter if over-used.

Raised bedssome advantages… • Warm up quickly in spring.• Drain well; less compaction and erosion.• Increase available rooting area. • Can produce greater food production per

square foot.and some disadvantages…• Up-front labor and expense.• Dry out quickly if weather is hot and dry.• Don’t work on slopes, unless terraced.

Raised bed basics2-4 ft. wide; usually 6”-8” above grade; can be bordered with wood, stone, brick

“Instant” raised bed filled with a purchased soil/compost mix

Read the label!

Growing healthy transplants

Plant protectionFloating row cover

over beansShade cloth over

lettuce

Intensive gardening: getting the most per square foot

• Close planting• Vertical growth• Inter-planting• Succession/relay

planting

How close is too close??Correct spacing for big onions

Okra plants are too tight

Interplant to maximize production purslane is

edible!

Mustard Green on North Side of Tomatoes

Succession planting

• Requires planning• Transplants fill the

space quickly• Special attention to

water and nutrient needs

• Floating row cover for protection

Succession planting examples• Garlic (11/1)-cucumbers (7/1)-oats/clover (9/20)• Peas/favas (3/1)-squash (6/1)-kale (9/1)• Lettuce (3/20)-green beans (5/15)-broccoli (8/1)• Radish (3/1)-Asian greens (4/15)-eggplant (6/1)-

rye (9/15)• Cucumber (4/15)- green bean (7/1)-spinach

(9/20)

Weed management

• Weeds are plants that thrive in disturbed soil.• Best control methods:

– crop cover– hand-pull– sharp hoe– mulch

• Other methods: vinegar, flame weeder, commercial herbicidal soap.

Organic mulches • Prevent weed growth.• Moderate soil temperatures.• Conserve soil moisture.• Add to soil organic matter.• Should be spread after soil warms up.• Can provide habitat for pests along with

beneficial critters.

Examples: grass clippings, newspaper covered with straw, shredded leaves, compost

Synthetic mulches• Black plastic mulch warms the soil for

earlier, higher yields of warm-season crops.

• Red plastic mulch may produce higher yields of tomato than black plastic.

• Landscape fabric warms soil and allows water and air into soil. Can be re-used.

Drip irrigation: saves time and water

Growing up: using vertical space• Increase yields per sq. ft. • Fewer fruit problems; easier to pick, water,

and spray.• Adds complex texture to garden; enhances

ecosystem (shading, micro-climates.)

Fence out the critters

Container vegetables 8 cu. ft. of growing media

Whiskey barrel- 1-2 plant capacity

EarthBox- “self-watering” container

“Salad Table” Demonstration at Central Maryland Research and Education Center

“Salad Box”

MG advanced training workshops

Mixed greens cut at 1” above soil line

‘Contender’ snap beans

Preliminary results

• Average salad greens yield- 24 oz. per cutting per table

• Average snap bean yield- 7.5 lb. per table• Crop yields exceed those of in-ground

gardens.• Multiple tables or locations necessary to

maximize growth potential.• Pepper, cucumber, squash, and tomato need

frame depth >9 in.

Resources• Home and Garden Information Center (HGIC)

– 800-342-2507– http://extension.umd.edu/hgic

• Grow-It-Eat-It website– http://extension.umd.edu/growit

• Master Gardener state website– http://extension.umd.edu/mg

This program was brought to you by

Maryland Master Gardener Program

Howard County

University of Maryland Extension