Common Grackles in Iowa
When grackles are present in Iowa, when they nest, which native Iowa plants feed them, and how to host them in a USDA 4b–6a yard.
- Status in Iowa
- Summer breeder
- Nesting window
- April–June
- Broods
- 1–2 per season
- Hardiness zones
- USDA 4b–6a
When to expect grackles in Iowa
Common Grackles are summer residents in Iowa, arriving shortly before nesting begins in April and leaving after the young are independent. Through the season they feed on beetles, grasshoppers and earthworms.
Humid continental prairie state, with loess hills in the west and the Driftless Area in the northeast.
Nesting in Iowa
Across Iowa, grackles typically nest from April–June. Nest site: bulky cup in dense conifers, often in loose colonies. Females lay 4–6 eggs, incubate for 13–14 days, and young leave the nest after 12–15 days.
Hot, humid summers with thunderstorms.
- Common Grackles don't use nest boxes. Keep dense native shrubs and trees such as white oak, bur oak for nest sites.
- Delay heavy pruning of shrubs until after June.
Native Iowa plants that attract grackles
Of the regional native plants we track for Iowa, these 8 provide food or cover grackles use:
Acorns plus hundreds of caterpillar species for nestling food.
Drought-hardy prairie oak with large acorns and a heavy insect load.
Tubular flowers for hummingbirds and seed heads for finches.
Leave seed heads up through winter for goldfinches.
Prolific seed heads for finches and sparrows.
Annual native sunflower — the original feeder seed.
Late nectar for insects and fall seed for sparrows.
Native bunchgrass; winter seed and ground cover for sparrows and juncos.
Feeding grackles through the Iowa year
Grackles arrive in flocks and can dominate open feeders; weight-activated and caged feeders help keep smaller birds fed.
- Best foods: Cracked corn, Sunflower.
- In Iowa's summer: offer water and insect foods; natural food is abundant.
Frequently asked
Are grackles in Iowa year-round?
No. Common Grackles are summer breeders in Iowa and leave for the winter.
When do grackles nest in Iowa?
Nesting in Iowa typically runs April–June, with 1–2 per season. Clutches are 4–6 eggs, incubated for 13–14 days.
What native plants attract grackles in Iowa?
White oak, Bur oak, Wild bergamot, Purple coneflower, Black-eyed Susan, Common sunflower, New England aster, Little bluestem are native plants in Iowa that provide food or cover for grackles.
Common Grackles in other regions
Other backyard birds in Iowa
Sources
- Common Grackle — All About Birds, Cornell Lab of Ornithology
- Common Grackle life history — Cornell Lab of Ornithology
- Common Grackle — Audubon Guide to North American Birds
- eBird region overview and bar charts — Iowa
- USDA Plant Hardiness Zone Map (2023)
- Audubon Native Plants Database
Timing reflects typical patterns for the region as a whole; local dates vary with elevation and year. Check the linked eBird bar charts for your county.