Organic Gardening For Dummies^®, 2nd Edition

Introduction

This book is for people who want to grow food and maintain their landscape without using synthetic chemical pesticides and fertilizers. Organic gardening is more than just safe food, however, and it’s bigger than nontoxic lawns. Organic gardening is also about making conscious decisions and taking responsibility for actions that affect the world outside your back door, past the end of your driveway, and beyond the boundaries of your hometown.

Most people proudly admit to being environmentalists, but not everyone knows how to be a good steward of his or her own yard, let alone the entire planet. This book gets you started on the path to making healthier choices for your own garden and landscape.

About This Book

Organic gardening covers a lot of ground, so to speak — from maintaining a lawn and growing roses to harvesting fresh fruits and vegetables. If you’ve read this far, you must be curious about how to garden organically in your own yard. This book takes you step by step through building and maintaining healthy soil, encouraging helpful insects and other organisms, choosing problem-free plants, and getting your plants off to the right start. In addition to the basic concepts of organic gardening, it also includes information about how to grow vegetables, herbs, flowers, trees and shrubs, fruits and nuts, roses, and lawns — without harmful pesticides or synthetic chemical fertilizers.

Conventions Used in This Book

When I refer to plant hardiness — a plant’s ability to survive the winter extremes — I use the U.S. Department of Agriculture’s Plant Hardiness Zone Map, which you can find in Chapter 3. All temperatures are given in degrees Fahrenheit and measurements in feet or inches.

A lowercase x in a species name indicates a hybrid cross. C. x lavellei, for example, indicates the Lavalle hawthorn, a variety of Hawthorn (Crataegus species).

When I refer to a local extension office, I’m referring to government- or university-sponsored services that offer helpful information on gardening. Look under “Extension office” or “Cooperative extension service” in the phone book. The name of the extension office may also be preceded by the name of your local land-grant college, such as “Ohio State University.”

Following are a few more conventions, designed to help you navigate your way through the content:

Italic is used for emphasis and to highlight new words or terms that are defined.

Boldfaced text is used to indicate the action part of numbered steps.

Monofont is used for Web addresses.

What You’re Not to Read

Although we’d like to believe that you want to pore over every word between the two yellow covers, we know that you may be in a hurry or just want the basic information. To help you out, we’ve made the “skippable” information easy to recognize: It appears in sidebars or is marked by a Technical Stuff icon. While interesting and related to the topic at hand, this information isn’t essential for you to know to have success as an organic gardener.

Foolish Assumptions

In writing this book, I made some assumptions about you:

You want to create a safe, beautiful, and healthful place for your family to work and play.

You want to harvest the freshest, tastiest, and most nutritious fruits and vegetables possible.

You care about the environment and are looking for information that helps you care for your landscape in an ecologically sound way.

You’ve heard about organic gardening but you need more specifics and ‘perhaps some convincing that it’s right for you.

Whether you come to this book in total gardening ignorance or have some experience under your fingernails, you’ll find plenty of hands-on, how-to information to make your organic garden and landscape the best ever.

How This Book Is Organized

To make navigating through this book easier, it’s divided into parts. Each part contains chapters related to the part’s general topic.

Part I: Understanding the Basics of Organic Gardening

If you think you may want to become an organic gardener but aren’t sure what that entails, start with Chapter 1. I’ve provided enough scary statistics there to start you running down the path toward Chapters 2 and 3, which explain the basic concepts of organic gardening, from soil health to planning low-maintenance landscapes.

Part II: Soil and Fertilizers

Healthy plants and gardens start with the soil. Turn to this part to get started on testing soil; making compost; and buying and using natural, organic fertilizers.

Part III: Managing Pests

Turn to this part whenever you spot trouble in paradise and need to know what it is and what to do about it. Here you can find everything you need to know about insects, diseases, animal pests, and weeds, including specific control measures and products.

Part IV: Growing Organically in Your Yard and Garden

The chapters in this part describe how to grow the most popular vegetables, herbs, fruits and nuts, trees and shrubs, roses, flowers, bulbs, and lawns. In each chapter, I offer advice about how to get the best plants, how to plant and maintain them, and where to obtain more information.

Part V: The Part of Tens

Use the handy lists in this part to impress your friends at parties and win them over to an organic lifestyle. I’ve listed best organic practices and ten ways to have an eco-friendly home and landscape. Go spread the word!

Color photo section

The color photo section near the center of this book shows you some organic gardening techniques you can apply right away. Flip to the photo section for colorful inspiration, examples of organic controls, and details that would be difficult to spot in black-and-white photos.

Icons Used in This Book

This book uses a variety of icons to highlight really neat tips, common pitfalls, and other interesting and helpful information. Here’s what they mean:

If I think of something that saves you time or money or that helps you make a better decision, I flag it with this icon. This icon also appears by sources that help you find particular plants, equipment, or help.

This icon alerts you to actions that may be dangerous to you, your plants, or the environment. Proceed with caution!

If it’s good for the environment, I’ve flagged it with this icon. For earth-friendly methods, look here.

This icon flags principles and practices key to organic gardening.

This icon marks more in-depth information for readers who want to dig a little deeper into the subject. If you just want to know the basics, feel free to ignore the info you find here.

Where to Go from Here

This book is designed so that you can jump into any chapter that grabs your attention. New to organic gardening? You probably want to start in Chapter 1. Interested in planting a vegetable garden? Go to Chapter 13. If you don’t know where to start, thumb through until something catches your eye, head to the Table of Content for general topics, or go to the index for specific topics.

Part I

Understanding the Basics of Organic Gardening

In this part . . .

Not sure what organic gardening is all about? Jump right into this part for an overview of what organic means. Chapter 1 introduces the foundations of organic gardening, along with basic techniques you’ll use whether you’re growing edibles, flowers, or lawn and landscape plants. Chapter 2 describes the benefits of gardening organically, as well as the risks to you and to the environment of using synthetic pesticides. If you need to justify your organic preferences to naysayers, you’ll have plenty to say after reading this chapter.

Evaluate your landscape conditions, such as sun exposure and soil moisture, with help from Chapter 3. And if you’ve ever wondered about microclimates and plant hardiness, this chapter is the place to turn. After gathering this information, you can begin planning your organic oasis; Chapter 3 also explains how to create a landscape map.

Chapter 1

Basic Techniques in Organic Gardening

In This Chapter

Understanding the philosophy behind organic gardening

Nurturing the soil

Diversifying your garden

Managing pests

Practicing conservation

Everyone agrees that organic gardening means avoiding synthetic fertilizers and pesticides. But the philosophy and practice of organic gardening go far beyond that simple concept. Growing organic food, flowers, and landscapes represents a commitment to a sustainable system of living in harmony with nature. For many people, organic gardening is a way of life. This chapter deals with the fundamentals of organic growing, including the philosophy behind organic gardening and the specific techniques that lead to success.

Defining Organic Gardening

The ways that people use — and misuse — soil, water, and air affect the lives and habitats of plants, insects, birds, fish, and animals, as well as humans. Organic gardening is all about preventing and treating problems in the least obtrusive, most nontoxic ways. Dedicated organic gardeners adopt methods that use cultural and natural biological processes to do the following:

Improve soil health and fertility: Organic gardeners nurture the soil ecosystem by adding organic matter, such as compost, and avoiding pesticides that can harm soil life. In turn, soil organisms consume and break down the organic matter, making the nutrients it contains available to plants.

Decrease erosion: Exposed soil is vulnerable to erosion by rain and wind. By covering soil with mulch, cover crops, or other protective materials, organic gardeners preserve the integrity of this precious resource.

Reduce pests and diseases: Organic gardeners minimize pest problems and reduce the need for pesticides by relying on cultural techniques, such as proper pruning, removing unhealthy plant material, and using row covers.

Encourage plant and animal diversity: Through diverse plantings and judicious use of pesticides — even organic ones — organic gardeners promote healthy ecosystems that invite beneficial organisms, including pollinators and predators of garden pests, to take up residence.

Organic gardeners take their cues from nature. Instead of relying on the spray schedules promoted by pesticide manufacturers, organic gardeners observe what’s going on in their gardens and intervene to prevent pest problems. When you see white butterflies fluttering around your garden, for example, you know it’s time to protect your cabbages, broccoli, and cauliflower from cabbage worm. Instead of sprinkling on a pesticide after the caterpillars hatch, you can cover the plants with a special fabric to prevent the butterflies from laying eggs in the first place.

Organic growers view their gardens as living ecosystems and work with nature to produce beautiful landscapes and healthy foods. No matter what plants you’re growing — vegetables, fruits, herbs, trees, flowers, grasses — the same basic techniques apply, as the following sections show.

Depleting soil fertility, damaging and polluting ecosystems, and consuming excess water threaten the future of Earth’s safe and abundant food supply. The ways that farmers and individual gardeners and homeowners choose to farm, garden, and maintain their landscapes make a difference in whether the land can continue to house, feed, and clothe us. Gardeners around the globe have adopted organic gardening techniques to help nurture the health of the Earth and all its inhabitants. (If you need more convincing that organic is the way to go, turn to Chapter 2.)

Building Soil

Just as a durable house needs a strong foundation, healthy plants require soil that can provide their roots with nutrients, water, and air. Few gardeners are blessed with perfect soil, and even if they were, keeping soil healthy and able to support plants is an ongoing process. Building and maintaining healthy soil is the single most important thing you can do to ensure the success of your garden and landscape plants.

Building soil means providing soil life — microbes, worms, fungi — with the materials and environment they need to do their jobs. Taking from the soil without giving anything back breaks the natural cycle. Harvesting crops, bagging lawn clippings, and raking fallen leaves removes organic material that’s ordinarily destined for the soil on which it falls. If the organic material isn’t replenished, soil health declines. Substituting synthetic chemical fertilizers for naturally occurring nutrients may feed plants, but it starves the soil.

Adding organic matter is the most common — and most important — part of building soil. Compost is a perfect source of organic matter; other sources include aged manures and crop residues. Maintaining proper soil pH (a measure of acidity/alkalinity) is also vital, because it affects soil life and the ability of plants to use nutrients.

Avoiding things that damage soil is just as important. Compaction from heavy foot or vehicle traffic and misapplied fertilizer and pesticides, for example, can harm the soil’s ability to support plant life. Part II tells you everything you need to know about your soil and how to improve it in an organically sound way.

Planting Wisely

Organic gardens strive to maintain healthy, balanced ecosystems. Because plants evolved over millennia to adapt to specific growing conditions, they thrive when those conditions are met. By choosing plants that match a garden site’s sun, shade, climate, soil type, and soil moisture, you’ll be well on your way to creating a healthy, thriving, pest-free landscape.

The first step in planting wisely is understanding your region’s climate, as well as your landscape’s particular attributes. Then you can effectively match plants to planting sites. You can find out more about evaluating your landscape in Chapter 3. For specific planting information and the lowdown on growing a wide variety of plants organically — vegetables, fruits, nuts, herbs, and flowers — go to the chapters in Part IV. You can also find information in that part on applying organic principles to lawn care.

The second step is ensuring that your garden cultivates stable plant and animal communities. In nature, plants and animals live in ecosystems — communities in which each part contributes to and affects the lives of the other parts. In a balanced ecosystem (see Figure 1-1), each plant and animal species has enough food, water, and habitat (place to live).

In a balanced ecosystem, the predators have enough prey, and the prey have enough predators. When one part of an ecosystem dies out or becomes too scarce, the plants and animals that depend on its function in the environment get out of balance, too. If honeybees disappear, for example, the plants that need bees for flower pollination won’t be able to produce seeds. If predators such as ladybugs become scarce, the insects they normally prey on — aphids — will become so numerous that they will seriously injure or even kill the plants on which they feed.

Ensuring diversity of plant types

Organic gardeners mimic nature by encouraging diversity in their landscapes. Natural plant communities contain many species of trees, shrubs, and perennial and annual plants. This rich diversity helps each plant species survive in many ways:

Mixed populations avoid insect and disease devastation because all the plants of a particular species aren’t located next to one another. While pests damage or kill some plants, they overlook others.

Deep-rooted plants often bring soil nutrients to the surface, where they are released by decomposition, benefiting more shallow-rooted species.

Nitrogen-fixing plants, which can take nitrogen from the air and deposit it in the soil, benefit other species nearby.

Tall, sun-loving species provide shade, shelter, and support for lower-growing, shade-preferring species.

When plants grow artificially in monocultures, which are large colonies of a single species, they lose the benefits of a diverse plant community. Pests and diseases spread easily from one plant to the next, and plants rapidly deplete the soil of nutrients. A good example of the risks of monoculture is the American elm, which was planted as a shade tree along streets across the country. When Dutch elm disease was inadvertently introduced in the late 1920s, its carrier, the elm bark beetle, flew from tree to tree spreading the disease.

Many farmers and gardeners recognize and take advantage of the benefits of polyculture — growing more than one crop in a field. Growing plants that mutually benefit one another makes sense and is simple to do in home gardens and landscapes. You can add clover to your lawn, for example, because clover takes nitrogen from the air and adds it to the soil. Also, you can plant shade-loving, ground-covering plants under leafy trees to protect soil and tree roots from erosion.

Encouraging animal and insect diversity

A variety of plants naturally invites a variety of wildlife and insects. Berry-producing trees and shrubs attract birds; nectar-rich flowers draw butterflies and hummingbirds. Why, you may ask, do you want to encourage wildlife and insects in your garden? Answer: Your garden needs them. Beneficial insects and other creatures prey on plant pests and pollinate plants. Some of gardeners’ best friends include ladybugs; syrphid flies; and tiny, nonstinging parasitic wasps.

Encourage beneficial creatures by providing a variety of habitats. Plant a variety of flowers so that something is in bloom all season long. Particularly good choices are herbs, such as basil and cilantro; plants with tiny flowers, such as alyssum and thyme; and plants whose small blooms are arranged in flat-topped flower heads, including yarrow and dill. Avoid spraying insecticides, because most of them will harm beneficial creatures too; see Chapter 7 for more information.

Here are some other ways to encourage diversity:

Provide specific foods for the organisms you want to attract. Plant parsley for the larvae of swallowtail butterflies or milkweed for monarchs, for example.

Build shelters designed for birds, butterflies, native bees, and toads.

Mimic nature by creating a layered garden with tall trees, medium shrubs, and lower-growing perennials and annuals.

Include a variety of different plants, including some evergreens, to provide winter habitat and food.

Provide a source of fresh water.

Leave a section of your yard wild, or at least minimally cultivated.

In most natural ecosystems, pests and predators are in a balanced but dynamic relationship. Coyotes and bobcats keep rabbits and rodents in check; without these predators, the rapidly reproducing prey would soon overpopulate, leading to death by starvation. Pests also have a place in your garden because they provide food for beneficial organisms — if food is scarce, the beneficials will starve or leave. The tiny, nonstinging braconid wasp, for example, is a beneficial insect that helps control pest caterpillars called hornworms. The wasp reproduces by laying its eggs on a hornworm. The eggs hatch and the developing wasps slowly devour the caterpillar as they mature. If you kill every hornworm, including the parasitized ones (as evidenced by the white cocoons along its back), you’re killing the next generation of beneficial braconid wasps. Tolerating some pests will assure predators that your garden is a good place to hang around.

Using Integrated Pest Management

When faced with pest problems, many gardeners automatically reach for a can or jar of poison. Using pesticides to kill insects deprives the pests’ natural predators of food, which causes the predators to decline, necessitating more pesticides to achieve pest control (refer to the preceding section for details). It’s a vicious cycle. In addition, pesticides often kill more than just their intended targets. Beneficial insects and spiders that prey on plant pests and pollinate flowers die, too. And if pesticides drift on the wind or water away from their target, fish and birds may be poisoned as well.

Organic gardeners choose a different approach. Instead of fighting pests and disease with chemical warfare, organic gardeners strive to create healthy, balanced ecosystems. If pest problems arise, the gardeners look first for the least toxic, least environmentally disruptive solutions.

Integrated pest management (IPM) combines biological, cultural, physical, and chemical strategies to control pests. In plain English, that means using the easiest, least environmentally harmful, cheapest methods first and using the more expensive, toxic methods only as a last resort.

Managing pests through IPM involves the following steps:

1. Prevention.

Keeping pests and diseases out of the garden in the first place is more than half the battle won. Inspecting new plants, cleaning your tools, eliminating weeds, and using best watering practices help prevent the spread of potential problems.

2. Crop monitoring.

You have to know exactly what pest you’re dealing with, when it appears, how many individuals you have, and on what plants.

3. Cultural controls.

Strategies such as rotating crops to avoid planting related plants in the same spot each year and choosing pest-resistant varieties will minimize problems.

4. Mechanical controls.

You can prevent pests from getting on your plants in the first place. Examples include covering plants with special fabrics or using hot water, air, fire, and the heat of the sun to kill pests without poisons. Simply knocking pests into a can of soapy water does the trick too.

5. Biological controls.

Take advantage of nature’s law that every organism has a natural control. You can buy and release many of these control organisms, such as ladybugs and beneficial nematodes, or encourage the ones that already exist around your garden.

6. Chemical controls.

Chemicals are the last resort. Start with the least toxic pesticides, choosing kinds that target only the pest and don’t affect innocent bystanders, such as bees and spiders.

Part III is devoted to pest management.

Managing Nutrients

Plants need nutrients to grow; flourish; and fend off pests, diseases, and environmental stresses. Giving them what they need is a key to successful organic gardening, but as with humans, overdoing poor food choices spells trouble. The best way to feed plants is to feed the soil. Vast numbers of beneficial organisms call the soil home; nourish them, and you nourish the plants. Adding organic matter, such as compost, provides fungi, bacteria, earthworms, and other soil dwellers both food and a hospitable environment. In turn, they break down this organic matter into nutrients that plants can use.

In some cases, you may need to apply extra nutrients to keep plants healthy. Using organic slow-release fertilizers encourages strong, steady, healthy plant growth. Most organic fertilizers provide a broad range of nutrients, and they won’t harm soil life or hurt plant roots.

The synthetic fertilizers that conventional gardeners use provide a few specific nutrients in a form that plants take up immediately. They make plants grow quickly but don’t necessarily make them grow strong and healthy because fast-growing leaves and stems are soft and juicy — and very inviting to pests. Plus, any applied nutrients that the plants can’t use are wasted, sometimes running off to pollute waterways. Synthetic fertilizers usually come in concentrated liquids or granules that you must dilute in water, and improperly diluted solutions can burn plant roots.

Turn to Chapter 5 for information on soil-building, and see Chapter 6 for information on organic fertilizers.

Conserving Inputs

Most organic gardeners are conservative — in the true sense of the word. We reduce, recycle, reuse, and in general try to limit what we buy. In the garden, conservation means reusing the nutrients contained in plant matter by composting kitchen scraps and garden trimmings. It also means taking care not to waste water and making sure that the products you use in your garden don’t put an undue burden on the environment.

Water

Communities across the country are experiencing record drought, and some municipalities are enacting watering restrictions. A well-designed, organic landscape adapts better to restricted watering because the soil has been nurtured and plants are well adapted. Still, even organic gardeners must water once in a while.

The ideal watering system applies moisture directly to the place where it’s needed: the roots. Soaker hoses and drip irrigation are best; they apply water slowly, right to the soil, where it can soak in rather than run off. Overhead sprinklers are worst, especially if they’re used on a hot, sunny day. Up to one third of the water applied is lost to evaporation, and water inadvertently applied to driveways and sidewalks runs off into storm drains, carrying pollutants with it.

Consider the source

Look at where the products you use in your garden originate. You may be surprised. Is using bagged bark mulch shipped thousands of miles good for the environment, especially if local mulch is available? Does it make sense to buy bat guano from distant caves when a local farm can supply aged cow manure?

As the price of fuel rises, the cost of shipping goods thousands of miles will force consumers to look for products that originate closer to home. You may be surprised by what you can find just down the road: wood shavings from furniture factories; grounds from nearby coffee shops; brewery waste; mulch from municipal Christmas-tree-recycling programs and tree-trimming companies; and small-scale composting operations.

Think creatively! I buy the ends of newsprint rolls from the printer of our daily paper. Instead of laying down individual sheets of newspaper under mulch to prevent weeds — a daunting task on a breezy day — I simply unroll the newsprint and spread mulch as I go. Shredded paper is a good addition to the compost pile.