Common Grackles in Colorado
When grackles are present in Colorado, when they nest, which native Colorado plants feed them, and how to host them in a USDA 3a–7b yard.
- Status in Colorado
- Summer breeder
- Nesting window
- April–June
- Broods
- 1–2 per season
- Hardiness zones
- USDA 3a–7b
When to expect grackles in Colorado
Common Grackles are summer residents in Colorado, arriving shortly before nesting begins in April and leaving after the young are independent. Through the season they feed on beetles, grasshoppers and earthworms.
Semi-arid high plains in the east and the Rocky Mountains through the center, with most backyards between 5,000 and 7,000 ft.
Nesting in Colorado
Across Colorado, 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.
Warm, dry days and cool nights; afternoon storms are common in July and August.
- Common Grackles don't use nest boxes. Keep dense native shrubs and trees such as gambel oak for nest sites.
- Delay heavy pruning of shrubs until after June.
Native Colorado plants that attract grackles
Of the regional native plants we track for Colorado, these 8 provide food or cover grackles use:
Tubular flowers for hummingbirds and seed heads for finches.
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.
Insect-rich in fall and seed in winter.
Acorns for jays and woodpeckers across the southern Rockies.
Nectar-rich in summer, seed for finches in fall.
Feeding grackles through the Colorado 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 Colorado's summer: offer water and insect foods; natural food is abundant.
Frequently asked
Are grackles in Colorado year-round?
No. Common Grackles are summer breeders in Colorado and leave for the winter.
When do grackles nest in Colorado?
Nesting in Colorado 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 Colorado?
Wild bergamot, Black-eyed Susan, Common sunflower, New England aster, Little bluestem, Tall goldenrod, Gambel oak, Rocky Mountain bee plant are native plants in Colorado that provide food or cover for grackles.
Common Grackles in other regions
Other backyard birds in Colorado
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 — Colorado
- 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.