March is the great turn in Idaho's lowlands. The Snake River Birds of Prey raptors return to their canyon cliffs in force, Greater Sage-Grouse begin their dawn dances on the high-desert leks, and snow geese and waterfowl pour through the Snake River Plain on their way north — one of the state's very best birding months.
Week by week in March
February 26 – March 4
- Snow Geese and Tundra Swans begin staging on the Snake River Plain wetlands as the great waterfowl push north gets underway.
- Sagebrush buttercup spreads across warm canyon and foothill slopes, joined by the first yellow bells and spring beauty in the moister draws.
- Leo climbs the eastern sky after dark while Orion still rides high in the south over the clear late-winter nights.
- Sow peas, spinach, and radishes in the warmest Treasure Valley beds as the soil dries enough to work.
March 5–11
- Greater Sage-Grouse begin their dawn strutting displays on the high-desert leks, and Prairie Falcons return in force to the Snake River canyon cliffs.
- Yellow bells and spring beauty open in the lower Salmon and Clearwater canyons, Idaho's mildest, earliest wildflower country.
- Greenhouse spinach, lettuce, and green onions bring the first fresh growth of the year to Boise and Twin Falls markets.
- Riverside aspen and cottonwood break their first buds in the warmest valleys as the snowline begins to climb the foothills.
March 12–18
- Clouds of Northern Pintail, American Wigeon, and Green-winged Teal stage on the Snake River Plain wetlands and the Deer Flat and Camas refuges.
- Plant seed potatoes and onion sets and set out hardy brassica transplants in the Treasure Valley; start tomatoes and peppers indoors.
- The Big Dipper rides high overhead, its handle arcing to Arcturus rising in the east on the lengthening spring nights.
- Arrowleaf balsamroot leaves push up on the Boise Front as the south-facing foothills green and freckle with early bloom.
March 19–25
- Mountain Bluebirds flash blue along the foothill fences, Say's Phoebes and Tree Swallows arrive, and Long-billed Curlews display over the Camas Prairie.
- Sagebrush buttercup, larkspur, and grass widows fill the warming Boise Front and canyon grasslands as the spring bloom accelerates.
- Serviceberry and chokecherry flower white along the canyon edges, and ornamental plums and cherries bloom in town.
- The spring equinox near March 20 evens day and night; Leo and the rising Beehive Cluster mark the changing season.
March 26 – April 1
- Burrowing Owls stand at their ground-squirrel burrows in the Snake River Birds of Prey country as Ferruginous and Swainson's Hawks return to territory.
- Overwintered Mourning Cloaks and tortoiseshells patrol the riverside woods, joined by the first fresh Sara Orangetips on the warm foothill slopes.
- Direct-sow carrots, beets, and lettuce and plant asparagus crowns in the Treasure Valley; keep row cover ready for late frosts.
- Rhubarb and overwintered green garlic and chives appear at the warmest valley stands alongside greenhouse greens.
Birds This Month
March is one of Idaho's premier birding months. The Snake River Birds of Prey National Conservation Area south of Boise comes alive as Prairie Falcons, Golden Eagles, Red-tailed and Ferruginous Hawks, and Northern Harriers set up on the canyon cliffs — the densest concentration of nesting raptors in North America, with the falcons keyed to the spring emergence of ground squirrels. On the high-desert leks of the sagebrush steppe, Greater Sage-Grouse begin their famous strutting displays at dawn, and Sharp-tailed Grouse dance on their own grounds.
Waterfowl migration peaks: Snow Geese, Ross's Geese, Tundra Swans, and clouds of Northern Pintail, American Wigeon, and Green-winged Teal stage on the Snake River Plain wetlands and the Camas and Deer Flat refuges. Sandhill Cranes return to the eastern Idaho valleys, Mountain Bluebirds — the state bird — flash blue along the foothill fences, and Say's Phoebes and Tree Swallows arrive.
What's Blooming
March opens the Idaho wildflower year on the warm, low slopes. Sagebrush buttercup spreads its glossy yellow across south-facing foothill and canyon ground in the Treasure Valley and the lower Snake and Salmon country, soon joined by the white-and-pink spring beauty (Claytonia), the yellow bells of Fritillaria pudica, and the first grass widows and shooting stars in the moister draws. The Boise Front foothills begin to green and freckle with these earliest blooms.
The canyon grasslands of the lower Clearwater, Salmon, and Snake rivers — Idaho's mildest microclimates — lead the show, with yellow bells, buttercups, and the first arrowleaf balsamroot leaves pushing up. Higher up, the mountains and the Camas Prairie are still snowbound and weeks from bloom. Along the rivers, the catkins of willow, alder, and black cottonwood open and dust the air with the first tree pollen of the year.
Garden This Month
March opens the outdoor garden in Idaho's warmer valleys while the high country waits. In the Treasure Valley and the southwestern fruit country, the soil dries enough to direct-sow peas, spinach, radishes, lettuce, carrots, and beets, and to plant onion sets, seed potatoes, and bare-root asparagus, rhubarb, and fruit trees by mid-to-late month. Cool-season transplants — broccoli, cabbage, and kale — can go out under protection toward the end of March.
Indoors, the seed-starting accelerates: sow tomatoes, peppers, and eggplant under lights now so they're ready for the warm-season transplant date in May. Watch the clear-night frosts, which run hard and late across the whole state, and keep row cover ready for sudden cold. In the eastern Snake River Plain and the mountain valleys, the ground is still frozen and the work stays indoors — Idaho's short, frost-bracketed high-valley season won't truly open for two more months.
Zone 4b (eastern Snake River Plain & mountain valleys): still mostly frozen. Keep starting seedlings indoors and prepping beds as they thaw, but outdoor sowing waits — the frost-free window here doesn't open until late May or June.
Zone 5b (Boise foothills & Magic Valley): sow peas, spinach, and radishes as soon as the soil dries enough to work, and start tomatoes and peppers indoors. Hold tender crops — hard frosts still come, so keep row cover handy.
Zone 6a (warmest Treasure Valley & lower Snake River): the outdoor season opens. Direct-sow peas, spinach, radishes, lettuce, and carrots, plant onion sets and seed potatoes mid-to-late month, and set out cool-season brassica transplants. Plant bare-root fruit trees and asparagus.
What's at the Farmers Market
March markets in Idaho are still in their lean late-winter phase, carried by storage crops and the first greenhouse greens. The Idaho potato remains the centerpiece — russets, reds, golds, and fingerlings still firm from cold storage — alongside storage Treasure Valley onions, carrots, beets, parsnips, cabbage, and winter squash, and dried Palouse lentils, split peas, and chickpeas from the northern Idaho hills.
The first fresh growth of the year appears from hoop houses and heated greenhouses around Boise and Twin Falls: tender spinach, lettuce, arugula, radishes, and green onions, plus the very first cuttings of overwintered chives and herbs. Idaho's value-added goods round out the stand — honey, dried beans and grains, hard cider, wine, and fresh-milled flour. Choose firm, unsprouted potatoes and store them cool and dark, pick crisp, bright greens and refrigerate them promptly, and keep dried legumes airtight in a cool pantry where they hold for a year or more.
Night Sky This Month
March balances long, dark nights with milder temperatures, opening Idaho's dark-sky country to more comfortable viewing. The Central Idaho Dark Sky Reserve around the Sawtooths, Stanley, and Sun Valley remains the premier destination — the first International Dark Sky Reserve in the U.S. — while Bruneau Dunes State Park resumes its spring observatory programs and the wide Snake River Plain and high Lost River country offer transparent skies for Treasure Valley and eastern-Idaho observers alike.
The sky is in transition: Orion and the Winter Hexagon sink into the west after dark while Leo climbs in the east and the Big Dipper rides high overhead, its handle arcing to Arcturus rising in the late evening. The spring equinox near March 20 evens the day and night. No major meteor shower peaks this month. For this year's exact planet positions and the latest aurora outlook, see the printable Idaho night-sky guide.
Butterflies & Pollinators
March brings the first real butterfly activity to Idaho's lower valleys. On warm, sunny afternoons in the Treasure Valley and the lower Snake, Boise, and Clearwater river country, overwintered Mourning Cloaks patrol the riverside woods, joined by waking Milbert's and California Tortoiseshells and the small, fast anglewings (Satyr and Green Commas), all of them hibernating adults taking advantage of the strengthening sun before any new generation hatches.
By late month, the season's first freshly emerged butterflies appear on the warm foothill slopes: the Sara Orangetip, flashing bright orange wingtips along the canyon grasslands as it tracks the earliest mustards, and early spring whites and azures. The Anise Swallowtail may begin hilltopping on the warmest lava-country ridges. The mountains and the Camas Prairie remain snowbound, their butterflies still weeks from flight, so all the action is low and sun-warmed.
Trees This Month
March stirs Idaho's lowland trees into spring while the mountains hold winter. Along the Snake River Plain and the southwestern valleys, the black cottonwood, willow, water birch, and aspen hang out fresh catkins and break their first buds, and the riverside quaking aspen groves begin to leaf in the warmest draws. The native chokecherry, serviceberry, and Rocky Mountain maple swell toward bloom, and in town the early ornamental plums and maples flower.
The conifer forests stand unchanged in dark green across the mountains — ponderosa pine on the canyon slopes, Douglas-fir and grand fir on the heights, and the great western white pine, western redcedar, and western hemlock of the north-Idaho panhandle. The bare, gray western larch waits among them for its spring needle flush. On the dry slopes, Rocky Mountain juniper and the silver of sagebrush carry their evergreen color as the snowline begins to climb the foothills.
Weather & Daylight
Across Idaho, a typical March day averages a high near 46°F and a low near 25°F, with about 2.4 inches of precipitation — statewide averages from the 1991–2020 U.S. climate normals.
Raw and unpredictable, days climbing into the 40s while nights dip below freezing, rain and late snow trading off.
| Average high | 46°F |
|---|---|
| Average low | 25°F |
| Precipitation | 2.4 in |
| Sunrise (mid-month) | 7:53 MT |
| Sunset (mid-month) | 19:44 MT |
Figures are statewide averages over the 1991–2020 U.S. climate normals; local conditions vary with elevation and distance from the coast. Sunrise and sunset are computed for a midstate point on the 15th (MT).
Next month's version of this page, by email
One short note when Idaho's next month turns — what's arriving, blooming, and worth a night outside.
Go deeper with the Idaho guides
The complete Idaho birding, native-plant, and night-sky references — or the whole year, week by week, in one book.
Same month elsewhere: March in Illinois · March in Indiana · March in Iowa