Colorado Nature Guide: March 2026
March is Colorado's marquee wildlife month, anchored by the great staging of tens of thousands of sandhill cranes in the San Luis Valley around Monte Vista. The prairie grouse begin their dawn dancing on the eastern plains, mountain bluebirds flood back to the foothills, and the first pasque flowers and spring beauties open below the still-snowy peaks.
What to look for this week
- Bald eagles fish the open tailwater below the South Platte and Arkansas reservoir dams as the lakes freeze.
- The Quadrantid meteor shower peaks around January 3 in a short, sharp burst best seen after midnight from a dark San Luis Valley sky.
- Deep-soak Front Range trees and evergreens on any warm, unfrozen day — winter desiccation, not cold, kills the most plants here.
- The bare plains cottonwoods along the rivers reveal the bulky stick nests of red-tailed hawks and eagles.
Birds This Month
March is the single greatest birding month in Colorado, and the spectacle is the sandhill crane migration. Some twenty to twenty-five thousand greater sandhill cranes stage in the San Luis Valley, feeding in the barley stubble around Monte Vista National Wildlife Refuge and roosting in the wetlands, and the long-running Monte Vista Crane Festival in mid-March is the event of the Colorado birding year. The valley also draws migrating waterfowl by the thousands and the occasional rare crane mixed in with the flocks.
On the eastern plains, the ancient theater of the prairie grouse leks begins. Greater prairie-chickens boom on their dancing grounds near Wray, the lesser prairie-chicken displays in the sand-sage country of the far southeast, and greater and Gunnison sage-grouse strut on their leks — the Gunnison sage-grouse, found only in Colorado and a sliver of Utah, dances near Gunnison and the Crawford area. Sharp-tailed grouse dance in the northwest. These dawn displays are timed-permit affairs at many sites, so plan ahead.
Spring migration sweeps the lowlands. Mountain bluebirds flood back across the plains and foothills, the first turkey vultures, say's phoebes, tree and violet-green swallows, and red-winged and yellow-headed blackbirds return, and the marshes fill again with sound. Waterfowl push north along the South Platte and Arkansas.
This month's tip: for the cranes, arrive at the Monte Vista refuge auto tour at dawn or dusk to catch the birds lifting off and returning to roost — the soft, rolling bugle of thousands of cranes at first light is unforgettable.
What's Blooming
March brings the first real wildflowers to Colorado's lowlands, even as the mountains stay deep in snow. On the sunny south-facing foothill slopes of the Front Range, the pasque flower (Pulsatilla) opens its silky lavender goblets through the matted grass and lingering snow, the great signature of the Colorado spring. With it come the year's first spring beauties (Claytonia), their tiny pink-striped white flowers carpeting moist foothill ground, and the earliest sand lilies (Leucocrinum) on the dry mesas and grasslands.
On the warmest plains and foothill ground, the small early bloomers stir — spring whitlow-grass, the first Easter daisies (Townsendia) hugging the gravelly soil, and the green-up of dryland grasses. The golden banner and other early lupines push leaves but hold their bloom for April. The high country is months from its great show, so the foothills and mesas of the Front Range and the lower Western Slope are the place to find March color, where the first warmth coaxes flowers from the thawing ground.
Garden This Month
March is when the Colorado cool-season garden finally begins along the Front Range and lower elevations. As soon as the soil has thawed and dried enough to crumble in the hand, direct-sow the cold-lovers — peas, spinach, lettuce, radishes, arugula, carrots, and beets — and get onion sets and seed potatoes into the ground, with cabbage and broccoli transplants going out late in the month under row cover. These crops want to mature before the intense early-summer sun and heat arrive, so earliness pays; in the mountains, this same work waits until May.
Indoors, keep the warm-season transplants growing strong under lights, because no matter how warm a March afternoon feels, the average last frost along the Front Range is still mid-to-late May, and a heavy spring snow is very much in play — March is in fact one of Denver's snowiest months. Prepare and amend beds, plant bare-root fruit trees, grapes, asparagus crowns, and rhubarb, finish dormant pruning before the buds break, and keep up the deep watering of trees and evergreens whenever a dry, windy spell follows the snow.
Zone 4b (mountain towns and high foothills): the season is still weeks away — the average last frost runs into late May or June up here. Keep starting onions, leeks, brassicas, peppers, and tomatoes indoors, prune dormant fruit trees, and resist the urge to plant outdoors. Begin hardening off the toughest greens only under cover at the very end of the month if the soil has thawed.
Zone 5a (cooler Front Range and foothill edges): the cool-season window cracks open at the end of the month. As soon as the soil is workable, direct-sow the hardiest crops — peas, spinach, radishes, and arugula — under cover, and set out onion sets late in the month. Keep warm-season transplants growing strong indoors; the last frost is still well into May.
Zone 5b (Front Range cities — Denver, Boulder, Fort Collins, Colorado Springs): the cool-season garden begins. Direct-sow peas, spinach, lettuce, radishes, arugula, carrots, and beets as soon as the soil is dry enough to crumble, set out onion sets and seed potatoes, and transplant cabbage and broccoli late in the month under row cover. Keep tomatoes and peppers indoors — the average last frost is still mid-May.
What's at the Farmers Market
Colorado markets begin to stir in March as the high-tunnel season ramps up, though the outdoor markets are still weeks from opening. The Front Range winter and indoor markets fill with the first abundant tender greens — spinach at its cold-sweetened best, leaf lettuces, arugula, kale, tatsoi, salad mix, and microgreens — alongside the first radishes and green onions.
The storage crops are still strong — San Luis Valley potatoes, storage onions, carrots, and beets, plus dried pinto beans — and vegetable and herb starts begin appearing at growers' stalls for home gardeners getting an early jump. Colorado pantry staples continue: local honey, eggs, grass-fed beef, bison, and lamb, milled flour, and the last of the frozen Pueblo green chiles.
For selection and storage: store tender greens dry and loosely bagged in the crisper and use them within a few days. Trim root-crop tops before refrigerating. Keep the remaining storage potatoes and onions cool, dark, and airy, and harden off any vegetable starts you buy before setting them out in the still-unsettled spring weather.
Night Sky This Month
March is the equinox sky over Colorado, a fine transition month with the winter brilliance setting in the west and the spring constellations rising in the east. The state's dark-sky strongholds remain superb — head for Great Sand Dunes National Park, the dark-sky town of Westcliffe-Silver Cliff in the Wet Mountain Valley, Black Canyon of the Gunnison, Dinosaur National Monument, or the plains darkness of Jackson Lake State Park. The dry, thin, high-altitude air delivers exceptionally steady, transparent skies once the spring storms pass.
In the early evening, Orion and the winter stars still hang in the southwest, while Leo the Lion now stands high in the east and the Big Dipper climbs in the northeast, its handle arcing toward orange Arcturus rising late. With no major meteor shower in March, it is a galaxy month for telescope owners — the galaxies of Leo and the rich Virgo Cluster ride high in the dark late-evening sky, beautifully placed from a dark Colorado site at altitude.
Because planet positions and exact timings change each year, check the printable Colorado night-sky guide for this year's specific viewing nights and planet visibility from your latitude. Watch for clear, calm nights behind the passing spring fronts, when the cold, dry air gives the steadiest seeing.
Butterflies & Pollinators
March brings the Colorado butterfly year back to life in the lowlands, even as the mountains stay frozen. The overwintering adults are out in force on warm afternoons along the Front Range and foothill canyons — mourning cloaks, Milbert's tortoiseshells, hoary and green commas, and the migratory California tortoiseshell patrol sunlit creek bottoms and bask on warm rock. They are joined by the first fresh spring fliers.
The little spring azure appears as a flake of pale blue along foothill woodland edges, the cabbage white begins working gardens and roadsides, the orange-tipped Sara orangetip flies along foothill streams, and early painted ladies push up from the south — in big invasion years painted ladies sweep across Colorado in remarkable numbers. The first western tiger swallowtails may emerge in the warmest river canyons by month's end. The high-country and alpine species, including the state insect Colorado hairstreak, are still dormant, awaiting the summer thaw. To help the early fliers, leave native nectar — the opening pasque flowers, willow catkins, and dandelions — and let standing stems and leaf litter stay put.
Trees This Month
March sets the Colorado lowland woods in motion while the mountains hold their snow. Along every plains and Front Range waterway, the great plains cottonwoods hang out their reddish catkins before leafing, and the bottomland willows flush with a haze of pale green and gold, the brightest sign of the turning year. The foothill Rocky Mountain junipers shed clouds of yellow pollen on the warm days, and the boxelders along the creeks begin to flower.
The early ornamental and orchard trees of the Front Range cities and the Western Slope fruit valleys begin to wake — silver and red maples open their tiny red flowers, and the first peach, apricot, and plum buds swell in the orchards around Palisade and Paonia, though a hard spring freeze can still threaten the crop. Up in the high country, the quaking aspen, blue spruce, ponderosa pine, and lodgepole pine remain locked in winter, their season of growth still a full two months away.
Go deeper with the Colorado guides
The complete Colorado birding, native-plant, wildflower, and night-sky guides — or the whole year in one bundle.
Same month elsewhere: March in Connecticut · March in Delaware · March in Washington, D.C.