When most gardeners think of a biodiverse garden their thoughts tend towards a garden teeming with birds, butterflies, beneficial insects and other wildlife. Following are several ways you can increase wildlife in your garden and thereby increase its biodiversity. There are also ideas on how you can add to the genetic diversity of the plants in your garden.  By creating a biodiverse garden you are adding to its beauty as well as helping to heal the planet and preserve it for future generations.

Following each discussion are links to resources, such as factsheets and other websites that will help you delve deeper to achieve your objectives. Have fun adding to the biodiversity of your garden and enjoy nature's bounty and diversity.  
 1. Attract birds to your garden

For birds to visit or live in your garden they need food and shelter, so plant trees and shrubs that provide these. Native plants are excellent choices. And, remember, leaving the seed heads on herbaceous perennials, such as coneflowers, for the winter is a good thing. Put off your final cleanup until late winter or early spring.

Start with these Plants

Aquilegia canadensis

Loved by hummingbirds.

Helianthus annus

Many birds will visit to eat the seeds.
Echinacea purpurea
Purple coneflower
Leave spent flowers standing and birds will visit for seeds.
Amelanchier arborea

The fruit is loved by many birds.
Malus cvs.
The fruit will be eaten by robins, cardinals and cedar waxwings.
Juniperus virginiana
Red cedar

Don't forget plants for nesting and cover!
The following resources provide excellent information to go further:
How do I Attract Hummingbirds?
Bird Gardening
 2. Add a butterfly garden

Butterflies add color and movement to a garden. If you want the colorful adults that feed on nectar flowers, you also need plants the larvae can feed on. The Kemper factsheet linked below lists excellent larval and nectar plants. Also, don’t use chemical pesticides in your garden or the organic pesticide Bt, which can damage or kill butterfly larvae.

Plant these nectar plants - Perennials

Rudbeckia fulgida
Black-eyed Susan 

Easy to grow with a long flowering period.
Liatris pycnostachya
Prairie blazing star

Another long-blooming plant with a dramatic spike of flowers.
Coreopsis lanceolata
Lanceleaf coreopsis

Most plants in the aster family are very good for birds.
Echinacea purpurea
Purple coneflower

A tough native plant that will readily re-seed.
Buddleja davidii 'Black Knight'
Butterfly bush

A butterfly magnet!
Asclepias tuberosa
Butterfly weed

A lovely plant essential for monarch butterflies.
Monarda bradburiana
Eastern beebalm

Attracts many pollinators including butterflies.
Vernonia baldwinii
Western ironweed
Late flowering and loved by butterflies.
Symphyotrichum novae-angliae
New England aster

Aster family plants are very attractive to butterflies.
Cephalanthus occidentalis

Thrives in wet locations.

Plant these nectar plants - Annuals

Pentas lanceolata
Egyptian star flower

Flowers all summer and an easy annual to grow.
Lantana camara

Easy to grow with lots of flowers all summer long.
Rudbeckia hirta
Black-eyed Susan

Easily grown as an annual and will perennialize.

Quick to grow from seed. Cut a few flowers to enjoy indoors as well.

Plant these larval plants 

(Fennel pictured)

Petroselinum crispum (Parsley), Anethum graveolens (Dill) and/or Foeniculum vulgare (Parsley)
Plant lots so you also have foliage to feed some caterpillars!

Asclepia syriaca
Common milkweed
Milkweeds are essential for monarch butterfly caterpillars.
Lindera benzoin

Plant for the spicebush swallowtail butterflies.
Quercus alba
White oak

An oak tree can support thousands of caterpillars!
Aristolochia tomentosa
Dutchman's pipe

Plant to enjoy the pipe vine swallowtail butterfly.
Ptelea trifoliata
Hop tree

Plant to enjoy the giant swallowtail butterfly.
Betula nigra
River birch

Plant for the mourning cloak butterfly.
Viola × wittrockiana

Plant pansies or let violets grow in your garden for the fritillary butterflies.
To go further, explore these sources for more information and plant recommendations:

Butterfly Gardening
How do I Plant a Butterfly Garden? 
St. Louis Milkweed for Monarchs Program
 3. Add a pollinator garden

There are many more pollinators other than honeybees but attracting honeybees is a good place to start. The Kemper factsheet (linked to below) will give the basics of bees. It also lists many plants that attract and support bees. How about becoming a beekeeper and raising bees? Also, why not expand your range and learn about the whole host of other pollinators? Explore the Pollinators.org website (linked to below) to learn more about pollinators and how to attract them. Beware of using pesticides in your garden. Honeybees and other pollinators are very sensitive to many insecticides. 

Start by adding these plants, which are very popular with honeybees and other pollinators

Helianthus annus

Long-flowering and frequented by bees.
Liatris pychostachya
Prairie blazing star

Visited by many Missouri native pollinators.
Tilia americana
Linden tree or basswood

When in flower the tree will be a buzz with pollinators!
Malus cvs.

Loved by bees.
Solidago rugosa 'Fireworks' 

A fall magnet for pollinators.
Vernonia baldwinii
Western ironweed

Great for fall flowering.
Pycnanthemum tenuifolium
Slender mountain mint

Plants can be covered with pollinators!
Physocarpus opulifolius Ninebark

A great shrub and attractive to pollinators.
To go further, explore these resources:

Pollinator.org website
 4. Add water to your garden

Adding water to your garden makes it very attractive to birds and other wildlife. Add a birdbath or a pond or stream. Running or bubbling water is particularly attractive to birds. A water garden can provide a habitat for a whole new palate of plants that will also attract a whole range of aquatic wildlife, such as frogs, dragonflies and fish. Consider a rain garden. It may be just the solution you need for a location where water accumulates.
For more information:

Rain Gardens
5. Add a log, build a rock pile or preserve a snag

A pile of logs or rocks can provide a home for wildlife. It can encourage beneficial snakes and toads to set up home or it could be a home for a family of chipmunks. When not in danger of causing harm to buildings or humans, a dead tree (called a snag) can be retained and preserved as a home for woodpeckers and other creatures that live in dead and dying trees. It is also a good perch for hawks and owls. Don’t just cut down a tree because it is dead, evaluate its potential use or danger first. If it is far from causing any damage to buildings or people, why not leave it standing for wildlife.

6. Add a birdhouse, bat house or native pollinator house

You can help attract birds, bats and pollinators to your garden by providing them good homes. Below are links to more information and plans for making homes for them. These can be fun projects to do with the kids or grandkids!
For more information:
Missouri Department of Conservation Woodworking Projects
Birdhouse and Birdfeeder Plans
Gourd Birdhouses
Build your Own Bat House
Garden for Wildlife: Build a Bat House
Nests for Native Bees (pdf)
 7. Decide how to deal with invasive plants

No matter how you feel about “invasive” plants, removing some or all of them from your garden will provide space for a wider range of plants. One of the most aggressive of the exotic, invasive plants are the bush honeysuckles. Two other aggressive, vining plants in the St. Louis area are Japanese honeysuckle and wintercreeper euonymus. Click on the links below for information on how to control these invasive plants.

Curse of the Bush Honeysuckle
Japanese Honeysuckle
Wintercreeper Euonymus

 8. Add more native plants to your garden

Plants native to Missouri are good choices for Missouri gardens. They are well adapted to the soil and climate. Many are very attractive and  provide excellent food and shelter for native wildlife, beneficial insects and pollinators.

Consider these exceptional natives for your garden 

Amsonia tabernaemontana

Sky blue flowers with lovely deer-resistant foliage.
Iris fulva
Copper iris A real dazzler and great for damp and wet areas.
Nyssa sylvatica
Black gum

Lovely tree with unsurpassed fall color
Spigelia marilandica
Indian pink

Striking flowers with attractive foliage.
Silphium laciniatum
Compass plant

Tall growing but a striking plant with bright yellow flowers.
Sassafras albidum 

Another small tree with gorgeous fall color. Will form a clump.
Quercus alba
White oak

One of the best trees for supporting beneficial insects.
Echinacea purpurea
Purple coneflower

The bright pink flowers are loved by all gardeners.

Follow these links to explore recommended native plants for Missouri gardens.

Shaw Nature Reserve Top Performing Native Plants
Native Plants in our Plant Finder

 9. Limit the use of pesticides and avoid preventative spraying

A biodiverse garden can have fewer problems with pests as it is also very welcoming to beneficial birds and insects that keep pest insects under control. Don’t jeopardize their activity by using pesticides in ways that can harm these beneficial helpers. Become an organic gardener or, at the very least, only use chemical pesticides when they are necessary in small localized areas and at times when beneficial insects are not present or active. Also select a pesticide that is least harmful to beneficial insects. Some good choices are insecticidal soap sprays as well as horticultural oils. Use these as your first choice when pest insect populations grow beyond the tolerable level. Organic pesticide alternatives:

A Guide to Beneficials in the Home Landscape 

 10. Enjoy your garden.
Yes, the last way to add biodiversity to your garden is to enjoy it. By taking the time to enjoy your garden you will notice more of nature around you and you will discover more ways you can enhance your garden. Adding biodiversity to your garden should be ongoing.