Arkansas Nature Guide: September 2026
Data updated: August 2026Sources & method · Corrections
September is the turn toward fall in Arkansas — the heat finally breaks, the monarch migration funnels through the state, and fall songbird migration fills the woods with warblers and the skies with hawks. The prairies blaze with goldenrod and aster as the Natural State eases into autumn.
Week by week in September
September 3–9
- Kettles of dozens or hundreds of migrating broad-winged hawks ride the thermals south along the Ozark and Ouachita ridges.
- The monarch migration funnels through the state; watch them fuel on goldenrod and aster over a sunlit prairie.
- New England and aromatic asters open purple alongside the gold goldenrod, the finale of the wildflower year.
- Plant garlic and shallots late in the month and set out the last cole-crop transplants.
September 10–16
- Ruby-throated hummingbirds pass through in good numbers before tapering off; keep feeders up for the last birds.
- Ozark apples come into the fall harvest as muscadines and scuppernongs reach their peak.
- Black gum glows scarlet in the bottomlands and sumac flames red along the roadsides as fall color begins.
- Clouds of yellow cloudless and sleepy sulphurs are showy over the fields and gardens.
September 17–23
- The fall equinox brings crisp, clearing nights; the Andromeda Galaxy rides high and the summer Milky Way arches in the west.
- The first blue-winged teal and early ducks return to the Delta as fall migration peaks.
- September is prime sowing time; direct-sow greens and roots and overseed cool-season lawns and cover crops.
- Little bluestem turns deep russet and the prairie grasses wave golden in the slanting autumn light.
September 24–30
- Scissor-tailed flycatchers gather in large flocks before departing south as the last fall migrants pour through.
- The first winter squash, pumpkins, and sweet potatoes arrive as the fall harvest begins in earnest.
- Sassafras begins its orange, red, and yellow display in the Highland woods and persimmons soften and sweeten.
- Late monarchs stream south, pausing to fuel on the blooming asters and ironweed.
Birds This Month
September is a peak fall migration month in Arkansas, and the woods and wetlands come alive with movement. The fall warbler wave pours through — American redstart, magnolia, black-and-white, Tennessee, and chestnut-sided warblers work the greening canopy in their subtler fall plumage — along with migrant vireos, thrushes, flycatchers, and tanagers moving south.
The ruby-throated hummingbirds are still passing through in good numbers early in the month before tapering off, so keep feeders up. Overhead, the hawk migration builds — broad-winged hawks form swirling 'kettles' of dozens or hundreds riding the thermals south, especially along the Ozark and Ouachita ridges, and Mississippi kites stream south from their summer haunts. The scissor-tailed flycatchers gather in large pre-migration flocks before departing late in the month.
In the wetlands, the shorebird migration peaks on the Delta rice fields and mudflats, the first blue-winged teal and early ducks return, and chimney swifts and common nighthawks stream south in their loose evening flights. The broad-winged hawk kettles and the monarch river are September's great spectacles.
This month's tip: watch the sky on warm, sunny afternoons for kettles of migrating broad-winged hawks riding the thermals along the mountain ridges, keep hummingbird feeders up for the last passing birds, and check the Delta wetlands for the peak of shorebird and returning-duck migration.
What's Blooming
September is the season of goldenrod and aster in Arkansas, the great finale of the wildflower year. The prairies, glades, and roadsides turn gold and purple as the many goldenrod species and a wave of asters — New England aster, aromatic aster, and the white heath and frost asters — bloom together, feeding the migrating monarchs and the last bees of the year.
The late prairie flowers carry on. Maximilian sunflower, showy sunflower, and the towering compass plant and rosinweed still bloom on the Grand Prairie and the Arkansas Valley glades, mixed with the deep purple ironweed and pink Joe-Pye weed. Along the streams, the scarlet cardinal flower and blue great blue lobelia finish their show, and the climbing passionflower ripens its egg-shaped maypop fruits along the fencerows.
Where to see it: the Grand Prairie remnants near Stuttgart, the glades of the Arkansas Valley and Ouachitas, and the mountain meadows of Mount Magazine and Petit Jean are at their golden best. The goldenrod and aster swarm with monarchs fueling up for the long flight to Mexico — September is the single best time to watch the migration over a blooming Arkansas prairie.
Garden This Month
September is one of the best gardening months of the Arkansas year, as the brutal summer heat finally breaks and the fall garden takes off. This is the prime window to direct-sow the cool-season crops for a fall and winter harvest: spinach, leaf lettuce, arugula, kale, collards, mustard, radishes, turnips, beets, and carrots all thrive sown now into the cooling soil, and you can set out any remaining transplants of broccoli, cabbage, and cauliflower early in the month.
The summer garden is winding down — harvest the last okra, peppers, southern peas, and the ripening fall tomatoes, and pull the spent, tired spring plants. Late in the month is the classic time to plant garlic and shallots in central and north Arkansas for harvest next summer, and to overseed or establish cool-season lawns and cover crops while the soil is warm and the rains return. The mild fall ahead gives Arkansas gardeners a long, productive second season — keep the new fall beds watered until the autumn rains settle in.
Zone 7a (Ozark and Ouachita valleys, Little Rock area): the fall garden hits its stride as the heat breaks. Direct-sow spinach, lettuce, radishes, turnips, carrots, and kale, set out remaining cole-crop transplants early, and plant garlic and shallots late in the month. The fall tomatoes are ripening now.
Zone 7b (south Arkansas and the lower Delta): the long, mild fall is prime growing time. Keep direct-sowing all the cool-season crops — greens, roots, lettuce, and peas — and the warm season lingers, so okra and peppers may still bear well into the month. Plant garlic toward month's end.
What's at the Farmers Market
September markets in Arkansas bridge summer and fall, with the season's crops overlapping richly. The last summer vegetables linger — vine-ripe tomatoes, okra, peppers, eggplant, and southern peas — while the fall crops arrive. The big fall fruit is the apple, with the Ozark orchards bringing crisp fresh-picked fruit, and the Southern muscadines and scuppernongs are at their peak.
The fall vegetables begin in earnest — the first winter squash (acorn, butternut, spaghetti), pumpkins for the coming season, sweet fall greens, and the first sweet potatoes as the harvest begins. Pears ripen in the orchards, the last melons finish, and fresh herbs, local honey, and pasture eggs round out the tables. Many markets hold fall festivals and pumpkin days as the season turns.
For selection and storage: choose apples and winter squash that are firm with no soft spots, and keep apples cold in the crisper and squash in a cool, dry place. Store muscadines cold and use them quickly. Keep the last tomatoes at room temperature, and cure newly dug sweet potatoes in a warm, dark spot before storing — never refrigerate them, which causes a hard core and off flavor.
Night Sky This Month
September brings the fall equinox and crisp, increasingly clear Arkansas nights as the summer humidity fades — often the start of the best stargazing stretch of the year. The state's dark-sky destinations are at their finest now: the Buffalo National River International Dark Sky Park in the Ozarks, the high overlook at Mount Magazine State Park, and the dark Ouachita National Forest, with Arkansas state parks running fall star parties under the clearing skies.
The sky is in transition. The summer Milky Way and the Summer Triangle of Vega, Deneb, and Altair still ride high in the early evening, but the autumn constellations are climbing in the east — the Great Square of Pegasus, the W-shaped Cassiopeia, and the chained princess Andromeda, which holds the Andromeda Galaxy (M31), the most distant object visible to the naked eye and a fine binocular target from a dark Ozark sky.
September has no major meteor shower, but the lengthening, clearer nights make it ideal for deep-sky viewing — the Milky Way star clouds in the west and the rising Andromeda Galaxy in the east are both superb. Because the planets shift position each year, check the printable Arkansas night-sky guide for this year's specific planet visibility and the best clear, moonless viewing nights from your latitude.
Butterflies & Pollinators
September is the month of the monarch migration in Arkansas, the butterfly highlight of the entire year. The special long-lived fall generation funnels down through the state on its way to the Mexican overwintering forests, and on a sunny day you can watch monarchs streaming south and pausing to fuel up on the blooming goldenrod, aster, and ironweed of the prairies — a moving, fragile spectacle.
The late-summer broods are still abundant alongside the migrants. The swallowtails — eastern tiger, pipevine, spicebush, and the huge giant swallowtail — fly into the fall, the bright orange Gulf fritillaries peak across the south on passionflower, and common buckeyes, painted ladies, sulphurs (the clouds of yellow sleepy and cloudless sulphurs are especially showy now), and many skippers crowd the late flowers.
To support them now: the fall nectar plants are the fuel that carries the monarchs to Mexico, so let the goldenrod, aster, ironweed, and Joe-Pye weed bloom, and add late garden flowers like zinnias and lantana. Leave the milkweed standing, avoid spraying, and simply enjoy the migration — a single blooming prairie patch can host dozens of southbound monarchs on a good September day.
What to plant for them is in the Arkansas native plants guide
Trees This Month
September is when the Arkansas forest begins its turn toward fall color, starting subtly and building through the month. The earliest trees to turn are the black gum (tupelo), glowing scarlet and crimson in the bottomlands and woods, the sumacs flaming red along the roadsides and old fields, and the sassafras beginning its orange, red, and yellow display in the Highland woods.
The trees are dropping their harvest now, the great autumn mast that feeds the wildlife. The oaks rain acorns, the hickories and pecans drop their nuts, the persimmons finally soften and sweeten on the branch (especially after the first frost), and the pawpaws finish ripening in the bottomland thickets. The black walnuts drop their green husked nuts in the river valleys. The crape myrtles finish their long summer bloom in town, and the bald cypress in the Cache River swamps holds its feathery green a while longer before its own late-fall turn. The pace of color quickens as the cool nights take hold.
The Arkansas native plants guide covers what grows with them
Weather & Daylight
Across Arkansas, a typical September day averages a high near 84°F and a low near 61°F, with about 3.7 inches of precipitation — statewide averages from the 1991–2020 U.S. climate normals.
Heat loosens its grip as highs settle near 84 and nights cool to the low 60s, with rain picking back up.
| Average high | 84°F |
|---|---|
| Average low | 61°F |
| Precipitation | 3.7 in |
| Sunrise (mid-month) | 6:52 CT |
| Sunset (mid-month) | 19:18 CT |
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 (CT).
Next month's version of this page, by email
One short note when Arkansas's next month turns — what's arriving, blooming, and worth a night outside.
Go deeper with the Arkansas guides
The complete Arkansas birding, native-plant, and night-sky references — or the whole year, week by week, in one book.
Same month elsewhere: September in California · September in Colorado · September in Connecticut