Mountain Bluebirds in Colorado
When mountain bluebirds 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
- Year-round resident
- Nesting window
- May–July
- Broods
- 1–2 per season
- Hardiness zones
- USDA 3a–7b
- Nest box
- 1 9/16 in hole, 5 × 5 in floor, 5–10 ft
When to expect mountain bluebirds in Colorado
Mountain Bluebirds live in Colorado all year. Cold snaps alternate with sunny, dry thaws; heated baths are valuable because natural water freezes nightly. That makes the cold months the time your yard matters most to them: their winter diet shifts toward juniper berries.
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, mountain bluebirds typically nest from May–July. Nest site: cavity or nest box. Females lay 4–8 eggs, incubate for 13–14 days, and young leave the nest after 17–21 days.
Warm, dry days and cool nights; afternoon storms are common in July and August.
- Have boxes cleaned and mounted before April — mountain bluebirds begin prospecting ahead of egg-laying.
- Use a 1 9/16 in entrance on a 5 × 5 in floor, mounted 5–10 ft.
- Fit a pole baffle or hole guard; ventilation gaps and drainage holes are essential.
- Clean out old nests after each brood and again after July.
Native Colorado plants that attract mountain bluebirds
Of the regional native plants we track for Colorado, these 8 provide food or cover mountain bluebirds use:
Red fruit heads hang on through winter.
Blue fruit on red stems in early fall.
Late nectar for insects and fall seed for sparrows.
Insect-rich in fall and seed in winter.
Fast-growing northern cherry with midsummer fruit.
Dark summer fruit and heavy caterpillar load.
White fruit and red winter stems; good thicket cover.
Berry-like cones feed bluebirds, solitaires and waxwings in winter.
Feeding mountain bluebirds through the Colorado year
Nests at high elevations in open country; takes nest boxes on fence lines.
- Best foods: Mealworms.
- In Colorado's winter: Cold snaps alternate with sunny, dry thaws; heated baths are valuable because natural water freezes nightly.
Full diet breakdown for mountain bluebirds · Best feeder for mountain bluebirds
Frequently asked
Are mountain bluebirds in Colorado year-round?
Yes. Mountain Bluebirds are year-round residents in Colorado.
When do mountain bluebirds nest in Colorado?
Nesting in Colorado typically runs May–July, with 1–2 per season. Clutches are 4–8 eggs, incubated for 13–14 days.
What native plants attract mountain bluebirds in Colorado?
Smooth sumac, Virginia creeper, New England aster, Tall goldenrod, Pin cherry, Chokecherry, Red-osier dogwood, Rocky Mountain juniper are native plants in Colorado that provide food or cover for mountain bluebirds.
What size birdhouse hole do mountain bluebirds need?
1 9/16 in, with a floor of 5 × 5 in mounted 5–10 ft.
Mountain Bluebirds in other regions
Other backyard birds in Colorado
Sources
- Mountain Bluebird — All About Birds, Cornell Lab of Ornithology
- Mountain Bluebird life history — Cornell Lab of Ornithology
- Mountain Bluebird — Audubon Guide to North American Birds
- NestWatch nest box plans and species requirements — Cornell Lab
- 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.