Creating A Healthy Garden Ecosystem

Pineapple Sage (Salvia elegans) is a favorite of hummingbirds and bees

In a previous post I wrote that by adopting certain gardening practices you can take advantage of “ecosystem services”, which provide pest control, healthy soil, thriving pollinators, and more.  The goal is to strive for a balanced system where natural processes are encouraged and thrive.

Why bother? In a healthy garden diseases and pests are minimized and you are contributing to the health of our environment overall. Here are my favorite tips for creating a thriving ecosystem in your garden.

The Basics: Food, Shelter, Water

To keep it simple think of it this way: an ecosystem is made up of living things and all living things need the basics: food, shelter (a home, i.e., habitat) and water.  In my garden a combination of California natives, ornamental plants (non-natives), and edibles make up a triad that buzzes with life. The native plants encourage wild pollinators and provide habitat and food. A careful selection of water-wise ornamental plants (a must in California) do the same. Edible plants are a diverse group that includes trees, herbs, perennials of many types, and annuals, which include many of our vegetables. In an ecosystem these plants have multiple roles. 

Scarlet Runner Beans have edible flowers that bees love 

Traditional Lawn Centered Gardens are Low on Diversity

Most traditionally designed gardens in urban areas do not have all of the three components above. The typical lawn-centered garden that is overly manicured with nary a leaf out of place is generally not very biologically diverse. Urban and suburban gardens are often designed to minimize leaf litter and emphasize a significant monoculture of lawn space. All lawns are not necessarily bad, it's the practice of using weedkillers and synthetic fertilizers that do the most harm to the ecosystem, in addition to wasting copious amounts of precious water. 

Furthermore, the flowering plants in these traditional gardens are usually not allowed to form seeds, and they aren't selected for their value as food for wildlife. In fact, some hybridized flowers don't produce pollen (sterile hybrids), which is considered a messy drawback for cut flowers brought into the house! 

In short, the traditionally landscaped garden is low on diversity, and a healthy ecosystem is just the opposite.

Transforming Your Garden 

The Big Three: Edibles, Natives and Ornamentals

In my garden, a combination of California natives, ornamental plants (non-natives), and edibles make up a triad that buzzes with life. I didn’t follow a formula to arrive at this combination- it happened naturally during the process of redesigning our yards. The native plants encourage wild pollinators and other beneficial insects, and provide habitat and food. A careful selection of water-wise ornamental plants (a must in California) do the same, as do edible plants.   

 Chamomile is a lovely ground cover with a delicate apple scent

Among my edible plants I’ve included a variety of perennial culinary herbs that insects love. These herbs have low water requirements: oregano, sweet marjoram, sage, rosemary, winter savory, lovage and different thymes. Allowing them to flower is critical. Not only do they attract pollinators, they are essential for cooking (the flowers are edible too), and can be cut back periodically after flowering to renew their foliage.  With these attributes they are popular in gardens for Mediterranean climates like ours in the San Francisco Bay Area.

Herbs are planted around my raised vegetable beds as permanent companions to seasonal vegetables to maximize pollination and bring in beneficial insects.

Flowering herbs and edibles ensure that my front yard is buzzing with life

Trees and Shrubs
A mature tree is extremely valuable and not readily replaceable. They provide us with numerous benefits that we take for granted at our peril.  A mature tree is an entire ecosystem that contributes (at a minimum) habitat for wildlife, shade, food, organic matter through leaf litter that feeds the soil as it decomposes, they transpire moisture into the surrounding air to regulate the local temperature, and their extensive root systems are part of the ecology of the soil food web. 

In keeping with my strategy of using natives, ornamentals and edibles, here are the trees in my garden: avocado, Meyer Lemon, a Blood Orange, Pomegranate, Santa Rosa Plum, a Pluot, a multigrafted apple, California Buckeye (Aesculus californica), Flannel Bush (Fremontodendron californicum), Coast Live Oak (Quercus agrifolia), and Crepe Myrtle (Lagerstroemia indica). 

Our shrubs provide a dense screen along our backyard fence and they are a favorite nesting place for local birds. They enjoy foraging on the ground where wood chips have replaced the lawns, and I provide water in two birdbaths for them.

A Morro Blood Orange

You can build your ecosystem over time as you learn more about the best plants to include for your climate zone.  It’s a lifestyle choice and gradual process of discovery. Select plants that have flowers and seeds attractive to the local wildlife.  

Birds enjoy hunting for bugs in my lush artichoke berm 

Remember that a healthy garden is lively with activity!

Related posts you might enjoy:
Maximize Free Ecosystem Services in Your Garden
The Rewards of a Seedy Garden
Your Garden as Wildlife Habitat
An Inspiring Talk by Toby Hemenway (author of Gaia's Garden)

Photos: Patricia Larenas, Urban Artichoke

Maximize Free Ecosystem Services in Your Garden

Carpenter bees are one of our local pollinators

By adopting certain practices you can maximize numerous free “services” to create a healthy and thriving garden, courtesy of Mother Nature. All you have to do is to make a safe home for her critters. A healthy garden doesn’t need extensive and expensive inputs such as pesticides, herbicides or even large amounts of fertilizers. In fact, you have to avoid using these toxic products.

I’m referring to ecosystem services, and what I mean is this: 

If your garden is a healthy ecosystem it is easier and less expensive to maintain, and it's healthier for you and the environment.

What are Ecosystem Services?

In a nutshell they are things that nature provides when the right conditions exist. The ecosystem services most important for home gardeners include: pollination, pest control, fertility through decomposition of organic matter, healthy soil leading to healthy plants, ambient climate control, food production, and even remediation (breakdown) of harmful contaminants.

Silver thyme in flower is much loved by bees

Here’s more on these points:

Pollination

Some edibles depend entirely on pollination to produce any crop at all, while others produce a better crop when pollinated. For example, include flowering plants that attract pollinators when you plant your vegetable garden and they will pollinate your crops for an optimal harvest. This is especially important for squashes and cucumbers which rely on pollination. Many fruit and nut trees require pollination, including certain varieties of apples, most plums, pluots, pears, cherries (except sour cherry) and nuts. To read more about attracting pollinators go to this Xerces Society page.

Pest Control

Birds, wasps, and other predatory insects will keep the “bad” bugs under control. They will also kill a certain amount of ”good bugs”, but a balance will eventually be established.  Efficient predators such as wasps prey on many insects and their larvae that feed on plants. It's critical that you don't use any toxic chemicals if you want to establish beneficial insects in your garden. Birds forage on the ground for insects and they also pick them off of foliage. Set out bird baths with water to attract them, and make sure they have shrubs and trees for their nests. To learn more about biological pest control go to this UC Davis page.

Crimson clover is another bee magnet

Decomposition and Healthy Soil

A healthy garden ecosystem is supported by healthy soil. A key process at work in the soil food web is the decomposition and recycling of organic matter. We typically remove valuable sources of organic matter when we rake up leaves, grass clippings, and other trimmings from our garden. We can return these to the soil in the form of compost, use a chipper to make mulch, or use wood chips as mulch. Mulch added around your plants to cover any bare soil, will be a source of organic material that will breakdown over time while it helps retain moisture. Composting your yard and kitchen waste is one of the most valuable practices you can do at home. There are many methods and you can find one that suits your lifestyle.

Soil is alive and teeming with microorganisms as well as larger creatures such as nematodes and earthworms, and many others. If you take time to build up your soil with good compost and provide proper amounts of moisture, your plants will thrive and be better able to access nutrients, resist diseases and insect damage. Read more about the soil food web.

A lovely flowering dogwood tree

Climate Control

Trees are essential for providing many much needed ecosystem services in suburban and urban areas. Not only do they shade our homes and offices but they also transpire water vapor, which cools the local environment around them. This added moisture creates favorable conditions for both plants and animals. Trees mitigate the "heat island" effect caused by overdeveloped areas that are low on vegetation. In dry climates like California, trees are an essential natural resource. And of course they also provide important habitat and food for birds, insects, and mammals. It’s true that when you cut down a tree you are destroying an entire ecosystem.  

Organically grown home-garden harvest- it's dinner time!

Food Production

Our food producing plants are fascinating - watching luscious tomatoes, strawberries and lettuce grow and transform into delicious food is magical. You can maximize your pleasure and quality of life by growing an endless variety of herbs, fruits, and vegetables to enjoy with your family, neighbors, and friends. Why not use your precious resources of land and water to grow at least some amount of food?
But besides food, edible plants contribute to a healthy garden ecosystem. For example, by letting herbs flower they attract scores of beneficial insects in addition to providing fresh herbs for your meal. Try oregano, thyme, rosemary, mint, basil, and parsley for starters.

Flowering parsley attracts beneficial insects

Bioremediation of Soil Contaminants

Through the process of decomposition some soil contaminants are eventually broken down. This process is a feature that can be leveraged through the use of compost (through the microorganisms). It has been used in clean ups for PCB, diesel fuel, and other petroleum type contaminated soils, to name a few. However, if you suspect that your soil is contaminated, you need to have it tested. I'm not suggesting that you should attempt to clean up serious or dangerous contamination on your own. I mention it here to show the power of natural processes.
To read more go here.

In my next post: Tips and strategies for creating a garden ecosystem.

Photo credits: Patricia Larenas, Urban Artichoke

What is Sustainable Gardening? My Test Case with Surprising Results

Replacing an old juniper hedge with a beautiful flowering, edible rosemary hedge that bees love is a good thing, right? In my sustainability analysis I'm surprised at my conclusions, but at peace with my decision.

Sustainability: What it is

What is meant by sustainable practices? At its core, it means taking into account the impacts of our actions on the environment, on people, and on economic concerns, so that we don't compromise the future. Deciding on whether to replace my standard- issue suburban juniper hedge with a rosemary hedge turned out to be a good test case. Here's why:

Sustainable gardening puts to use the principles of sustainability, and there is actually a document to point to for these so called Hannover Principles, also known as, a "Bill of Rights for the Planet", which are used as guidelines. They are credited to William McDonnell Architects and were developed for an  EXPO held in Hannover, Germany.

Recently I had a chance to apply these principles to my hedge replacement plan. I took a short course on  sustainable practices  through my horticultural program this summer and it was a good eye-opener that got me thinking deeper about my own approach to gardening. I have to give credit to instructor Frank Niccoli, a sustainable landscaper who teaches in my Environmental Horticulture and Design program.

My Test Case

We inherited the junipers when we bought our suburban home, and I've never found them attractive, in fact they irritate me.  They don't flower, they are prickly, and I don't like their odor. They are leftovers of gardening practices popular in the 50's and came with our house.  In contrast, rosemary is an attractive shrub with lovely sky blue to purple flowers that attract bees, has a wonderful fragrance, is useful in the kitchen and can be pruned into a hedge. It's also drought tolerant. On the surface it seems like an obvious decision to go ahead with my replacement scheme.

But I applied sustainable principles in analyzing my plan and I was surprised at my conclusions. See if you agree.

My Analysis

To remove the juniper hedge I would have to:

1. Pay someone to take out a row several feet long of these shrubs.

2. Pay to have the roots removed so that I could plant something in their place; leaving any roots means they might grow back.

3. Pay to have the waste from the shrubs be disposed of at the dump, because they cannot be used for mulch.

Additionally,

4. The energy use involved in removal and transportation to the dump are costs to the environment (pollution and use of petroleum based non-renewal energy).

5. The truckload of yard waste is needlessly adding to the landfill, which is a societal cost, since garbage keeps coming, but landfill space is limited.

The Benefits of Doing Nothing

Sometimes the best thing to do is nothing; here are the arguments for keeping the junipers:

1. The juniper shrubs have the advantage of being drought tolerant which is very important in my dry California climate.

2. There are currently no monetary or environmental costs to keeping the juniper hedge as is (I've been hand-pruning for the past several years).

My Conclusion

Sadly for my rosemary hedge fantasy, the resources required to replace the junipers with something I happen to like better far out weigh the benefits. Part of the equation is that I already have several rosemary bushes that provide herbs for my kitchen and flowers for bees. I also grow a profusion of other herbs and flowering plants that benefit my garden ecosystem.

Thinking in a New Way

“Sustainable design is not a reworking of conventional approaches, and technologies, but a fundamental change in thinking and in ways of operating–you cannot put spots on an elephant and call it a cheetah.”

- Carol Franklin, Andropogan Associates LTD.

A sustainable approach to gardening and to our lifestyles in general, means that we take a global approach to everything we do by weighing the impacts. For the gardener this means that we consider the inputs and the outputs of our home gardening practices. This simply means  that a minimum, we think carefully about the types of plants that we grow and landscape with, fertilizers we use, and what we do with garden waste.

In my test case the arguments in favor of replacing the juniper hedge with pollinator-attracting rosemary are weak when considered in the context of my particular garden.

Therefore, the junipers will live to see another day and having realized the real costs, it's a decision I can live with.

Photo: Patricia Larenas, Urban Artichoke