Just when many gardeners start winding down for the season, August whispers an invitation: Don’t stop yet — the best colors are still to come.
Planting in late summer isn’t just possible; it can be downright magical. The soil is warm, the days are long, and there’s still enough time for certain blooms to establish themselves and shine in the cooler days of autumn. With the right selections, your garden can stay vibrant long after summer annuals fade, and right before frost sweeps in.
In this guide, you’ll discover 10 fall-blooming flowers to plant in August — hardy, colorful, and ready to make your garden glow when everyone else’s beds are bare.
Why Plant Fall Flowers in August?
Planting in August might seem late in the game, but here’s why it works:
- Warm Soil Speeds Growth: Roots establish faster in late-summer warmth.
- Cooler Nights Encourage Blooms: Plants shift energy from foliage to flowers.
- Seasonal Gaps Get Filled: Many gardens look sparse after summer annuals fade.
- Pollinator Support: Fall blooms give bees and butterflies a much-needed food source before winter.
10 Fall-Blooming Flowers to Plant in August
1. Zinnias – The Late-Summer Workhorse
If you want color that doesn’t quit, zinnias are your best friend. Planting in early August in mild to moderate climates gives you fresh blooms by late September and well into October.
Why they shine in fall:
- Endless color options: bold reds, sunny yellows, bright pinks
- Attract butterflies and beneficial insects
- Minimal care required once established
Tip: Choose heat-tolerant varieties if August temperatures are still scorching in your area.
2. Marigolds – Golden Guardians of the Garden
French and African marigolds love warm soil and will bloom quickly after August planting. Their bold oranges and golds match autumn’s palette perfectly.
Why they shine in fall:
- Naturally repel some pests
- Thrive in less-than-perfect soil
- Ideal for borders and companion planting
Planting advice: Deadhead regularly to keep the flowers coming until frost.
3. Asters – Autumn’s Starry Skies
Asters are practically the poster child for fall gardens, with daisy-like flowers in blues, purples, and pinks. They’re perennial in many regions, but you can plant container-grown starts in August for fall blooms.
Why they shine in fall:
- Provide late nectar for bees and butterflies
- Offer vibrant cool-toned blooms that stand out against fall foliage
Pro tip: Choose compact varieties for containers or front-of-border planting.
4. Chrysanthemums – The Classic Fall Favorite
You can’t talk about fall flowers without mentioning mums. Planting hardy mum starts in August ensures they’ll establish roots and burst into color by mid-autumn.
Why they shine in fall:
- Huge range of colors and bloom shapes
- Tolerate cooler temperatures better than many flowers
Care tip: Keep soil evenly moist during establishment for the best bloom display.
5. Coreopsis – A Golden Glow for Autumn Beds
Coreopsis, sometimes called tickseed, brings a cheerful yellow hue that bridges the seasons between summer and fall.
Why they shine in fall:
- Long bloom period, often until the first frost
- Attract pollinators and are drought-tolerant
Best use: Plant in drifts for a meadow-like effect.
6. Snapdragons – Cold-Tolerant Charmers
While often planted in spring, snapdragons also thrive in late-summer planting, especially in cooler zones. They’ll bloom as temperatures drop, offering spikes of color in shades from soft pastels to deep jewel tones.
Why they shine in fall:
- Resist light frosts, keeping gardens colorful longer
- Work beautifully in mixed beds or as cut flowers
Extra tip: Pinch early growth to encourage bushier plants and more blooms.
7. Rudbeckia – Autumn’s Golden Rays
Also known as Black-eyed Susans, rudbeckia are heat- and drought-tolerant, making them perfect for planting in August when the sun is still intense.
Why they shine in fall:
- Warm yellow petals with dark centers embody autumn’s vibe
- Attract pollinators and are low maintenance
Pro tip: Combine with ornamental grasses for a naturalistic fall look.
8. Cosmos – Effortless Elegance
Cosmos can be direct-sown in early August in many climates for a quick pop of color before frost. Their airy foliage and delicate blooms in pink, white, and magenta sway beautifully in autumn breezes.
Why they shine in fall:
- Long stems perfect for cut arrangements
- Self-seed easily for future blooms
Care note: Avoid over-fertilizing; it can lead to more foliage than flowers.
9. Salvia – The Pollinator Magnet
Many salvia varieties bloom from summer into fall, but planting fresh starts in August ensures a colorful flush just as other blooms are fading.
Why they shine in fall:
- Intense purple, blue, or red flowers
- Loved by hummingbirds and bees
Extra bonus: Deer-resistant in most gardens.
10. Sedum ‘Autumn Joy’ – A Fall Garden Staple
This hardy perennial truly lives up to its name. By planting container-grown sedum in August, you’ll enjoy clusters of pink blooms that deepen to copper as the season progresses.
Why they shine in fall:
- Extremely drought-tolerant once established
- Provides winter interest even after flowers fade
Best use: Plant in sunny, well-drained spots for best results.
How to Plant Fall-Blooming Flowers in August for Best Results
1. Start with Healthy Soil
August planting still needs fertile, well-draining soil. Add compost to boost nutrients and water retention.
2. Water Wisely
New plantings need consistent moisture to establish quickly — but avoid waterlogging, which can cause root rot.
3. Mulch for Temperature Control
A 2–3 inch layer of mulch helps retain soil moisture and keeps roots cooler during hot August afternoons.
4. Watch the Sun
Most fall-blooming flowers need full sun (6+ hours daily), but in hotter zones, a touch of afternoon shade helps reduce stress.
Common Mistakes to Avoid When Planting in August
- Planting too late: Give plants enough time before first frost.
- Overcrowding: Allow space for airflow to prevent fungal issues.
- Ignoring heat stress: Shade new plantings during extreme heat spells.
Why Your Garden Will Thank You
Planting these 10 fall-blooming flowers in August ensures your garden stays lively when others fade into browns and grays. You’ll enjoy a burst of color, help local pollinators stock up before winter, and create a more dynamic seasonal landscape.
So before you pack away your trowel and gloves, take one last round through your garden — and plant for a spectacular autumn finale.