Cardinals never nest in nest boxes. Usually it takes from three to nine days to build their loose cup-like nest. After approximately a six day rest, egg laying begins. The eggs are covered in spots, dots, and blotches of grays, browns and purples with most of the color at the large end of the egg. They are on inch in length and weigh about 8.6 grams.
Incubations starts after the last egg of the clutch is laid and hatch in twelve to thirteen days.
The female is on the nest most of the time with the male taking over once in a while. He sits near her to sing or warn her of any nearby predators. He will feed her several times a day. The male will bring food to the young for the first few days and both will take on this tiring task. Small songbirds are fed between four and twelve times an hour per bird depending on the age.