The first of the four elements to provide for your wild visitors is food. While our first impulse is often to put out lots of bird feeders, the backbone of any wildlife feeding project should be food-bearing plants, preferably native plants.
Assess your yard as it is. Do you have plants that provide berries, nuts, or seeds? Do you provide plants that caterpillars can munch on? Are there plenty of nectar-producing flowers? If your yard is a little short on wild food, consider adding shrubs, trees, or herbaceous plants to create a wildlife cafeteria.
Here are some specifics to consider:
If you want butterflies, plant flowers, shrubs, and trees that will feed both adults and their larvae. Adult butterflies feed on nectar, but their larvae need the leaves of specific plants. Of course, that means that you will have to allow the larvae to feed on your plants, and not allow anyone to talk you into spraying for the voracious little things. Use the internet to find out which butterflies are common in you area, and the plants that they feed on. The Foremost Insurance Group has a nice list of the larval food plants and butterfly nectar plants in their butterfly garden. The Butterfly Site has great information on creating a butterfly garden.
In addition to flowers as nectar sources, you can also hang butterfly feeders in the garden. Here are instructions from All Free Crafts on how to make a butterfly feeder. Be aware, though, that open sources of sugary foods may attract hornets as well as butterflies.
Seed-eating birds will flock to bird feeders that are kept full. Don't fill them with cheap bird seed which contains filler seeds that birds don't like. Black sunflowers seeds are a good choice for most feeder birds throughout the year. Suet cakes are favored by many winter birds. Thistle or niger seeds will attract finches, especially goldfinches, and are a good summer food. Thistle should be offered in special thistle seed feeders. Be sure that feeders drain well to prevent the seeds from molding. Drill extra drainage holes in the bottom if you need to.
Be sure to provide lots of natural forage as well. Let your annuals go to seed, especially sunflowers, cosmos, and marigolds. If you have room, plant red-hot pokers, which attract hummingbirds and finches with their abundant nectar. Berries will attract fruit-eating birds, as anyone who has grown strawberries or blueberries can tell you! Try planting elderberry near your berry patch. Many fruit-eating birds favor the smaller elderberries over strawberries, and feel safer feeding from the taller elderberry shrubs instead foraging for strawberries on the ground. Serviceberry, rowan, Japanese aralia, and madrone all bear fruits that birds will feed on. The Japanese aralia, which grows well in full shade, provides winter fruit, and will be picked clean before winter is over. A wide variety of shrubs and plants will also attract an array of small insects, which provide forage for insect-eating birds.
For hummingbirds, provide plenty of nectar-rich flowers, such as honeysuckle, hardy fuchsia, red salvia, and hummingbird mint. Supplemental feeders should be filled with a syrup made of one part table sugar to four parts water. Sucrose -- table sugar -- is the same sugar found in natural flower nectar. Do not use honey, which can cause liver problems, and of course don't use artificial sweeteners which have no food value at all. Be sure the feeder is sparkling clean at all times to prevent fungal infections.
But think carefully...
There are some animals that you don't really want to attract. In our neighborhood I've seen raccoons, opossums, rats, and skunks. Raccoons are adorable and fun to watch -- until they break into your house and raid your cupboards. They're intelligent animals with dexterous paws and can learn to turn doorknobs. Besides the potential for raccoon break-ins, raccoons can harbor rabies, roundworms, and distemper. They also kill kittens may kill adult cats -- though I watched a big orange tabby tree a young 'coon once. 'Possums can break into sheds and houses, and can get into fights with cats. Rats are great for spreading disease, and can find all sorts of ways to get into houses. As for skunks, I think we all know why we don't really want them in the back yard!
To make your home less attractive to pesky sorts of wildlife, the number one rule is don't feed them! Don't leave pet food out at night, and be sure to secure all garbage cans. Don't even store pet food outside in one of those fancy containers with the screw-on lid. Raccoons can figure out how to get them open. I put our kitchen waste into an Earth Machine composter which has a fairly secure lid. This helps reduce the amount of food available to pests. Only weeds and other garden waste go in the open bins.
The entire Gardening for Wildlife series:
Gardening for Wildlife: The 4 Element
Gardening for Wildlife: Food
Gardening for Wildlife: Water
Gardening for Wildlife: Cover
Gardening for Wildlife: Nesting Sites