Plan garden enhancements that will attract birds

Late winter is a good time to plan enhancements to your garden with plants that will attract birds all year long. It takes more than feeders, bird houses and a bird bath, along with some flowers, for a truly bird-friendly garden.

Birds need a complete habitat that includes food, shelter, nesting areas and perching spots. A good bird garden tends to have more of a natural look to it. Use natural areas that have different vertical levels, each attracting and providing something important to different bird species as a guide for your garden.

Some birds prefer the canopy of tall trees while others perch in the understory trees and shrubs. Different species of birds will have varying requirements and preferences for nesting, eating and shelter. Try to create as many of these levels as possible in your backyard bird refuge to attract a larger variety of birds. Even open areas of soil can be beneficial by providing an area for birds to take a dust bath.

Select plants to provide food for birds at different times of year. Fruits of different plants will ripen in different seasons. For example, serviceberries provide spring-ripening fruit, red-twig dogwood provide fruit in summer, while hawthorns and crabapples provide fruit in fall and winter.

Perennials such as purple cone flower and grasses such as a prairie dropseed provide seed for a food source. Sunflowers are quick growing annual flowers that will produce seeds that are attractive to birds. Nectar-producing plants such as penstemon, Mexican bush sage and columbine are attractive to hummingbirds.

It is a good idea to include a mix of evergreens in your planting to provide year-round shelter for the birds. When possible aesthetically, leave some dead branches on living trees to provide zones for the birds to perch on. Prune any dead branches that are safety hazards, though.

If you feed birds in your garden, then it is a good idea to stop your dog (if you have one) from eating the fallen birdseed. The birdseed alone is probably not going to cause too many problems, unless the dog eats so much that its intestines become impacted.

Should a dog develop a large amount of gas in the stomach from the seeds fermenting, the dog's stomach can bloat, leading to a condition in which the stomach twists on itself. This is a life-threatening condition that requires immediate emergency veterinary attention. Most dogs can pass small amounts of ingested bird seed.

Another area of concern is that your dog can eat bird droppings, which may contain salmonella bacteria along with the bird seed. Salmonella can cause severe digestive upset, with lots of vomiting and diarrhea that can be fatal in very young or old dogs. The salmonella bacteria can also be passed on to you.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.