A Northern cardinal's nest usually holds three to five eggs, like those seen here. The cup-shaped nests of songbirds are said to be marvels of engineering. (Courtesy of marti175/Creative Commons) ...

He emphasizes that while feeders can be used to successfully attract cardinals, a well-planned garden also provides a habitat for nesting and encourages more opportunities to keep cardinals nearby.

We exposed nesting Northern Cardinals (C. cardinalis) to models of three predators of cardinal eggs or nestlings (black rat snake [Elaphe obsoleta], Blue Jay [Cyanocitta cristata], and eastern ...

While adding a birdhouse to your yard will attract many kinds of birds, if you're specifically trying to lure in cardinals, this may not be a good idea.

If you do, these provide great nesting options that can attract cardinals to your garden. There will be some indicators that your planting efforts are attracting cardinals.