Minnesota’s short growing season means August planting focuses on flowers that will bloom before the first frost. If you are looking for the best flowers to plant in August in Minnesota, you need varieties that can handle cooler nights and still put on a show. August is not too late to add color to your garden, but you have to pick the right plants.
Many gardeners think spring is the only time to plant. That is not true. August planting works great for fall blooms. The soil is warm, which helps roots grow fast. You just need flowers that mature quickly or tolerate light frost.
Best Flowers To Plant In August In Minnesota
These flowers are top choices for late summer planting. They will bloom before the first frost hits, usually in late September or early October. Some will even keep going after a light frost.
Marigolds
Marigolds are tough and reliable. They grow fast from seed or transplants. You can plant them in August and see blooms in three to four weeks. They love full sun and do not mind cooler nights.
- Plant in well-drained soil
- Water regularly until established
- Deadhead spent blooms for more flowers
- Choose dwarf varieties for faster blooms
Pansies
Pansies are cold-hardy. They can survive light frosts and keep blooming. August planting gives them time to root before winter. They will bloom in fall and come back in spring if mulched.
- Plant in partial shade to full sun
- Keep soil moist but not soggy
- Fertilize every two weeks
- Remove faded flowers to encourage new growth
Chrysanthemums
Mums are classic fall flowers. They are widely available in August. Plant them early in the month for best results. They need full sun and regular water. Mums will bloom for weeks until hard frost.
- Space plants 18 to 24 inches apart
- Pinch back stems until mid-July for bushier plants
- Water at the base to avoid mildew
- Mulch around roots for winter protection
Snapdragons
Snapdragons love cool weather. They bloom best in fall. Plant them in August for tall spikes of color. They come in many colors and heights. They can handle light frost without damage.
- Plant in full sun or light shade
- Stake tall varieties to prevent flopping
- Water deeply once a week
- Cut flowers for indoor bouquets to encourage more blooms
Calendula
Calendula is also called pot marigold. It grows fast from seed. You can sow seeds directly in the ground in August. They will bloom in six to eight weeks. The flowers are edible and bright.
- Sow seeds 1/4 inch deep
- Thin seedlings to 8 inches apart
- Water regularly in dry spells
- Harvest flowers for salads or teas
Asters
Asters are native to Minnesota. They bloom in late summer and fall. They attract pollinators like bees and butterflies. Plant them in August for a burst of purple, pink, or white.
- Plant in full sun for best blooms
- Water during dry periods
- Divide clumps every two to three years
- Cut back after flowering for neat appearance
Dianthus
Dianthus, or pinks, are low-growing and fragrant. They bloom in cool weather. August planting works well. They will flower until frost and often survive winter.
- Plant in well-drained soil
- Space 10 to 12 inches apart
- Water sparingly once established
- Remove spent blooms for repeat flowering
Ornamental Kale And Cabbage
These are not flowers, but they add color. They look like giant rosettes. They get brighter as temperatures drop. Plant them in August for fall display. They last through hard frosts.
- Plant in full sun
- Space 12 to 18 inches apart
- Water regularly until established
- No deadheading needed
How To Plant Flowers In August In Minnesota
Planting in August requires some care. The weather can be hot and dry. Follow these steps for success.
Prepare The Soil
Good soil is key. Remove weeds and rocks. Mix in compost or aged manure. This adds nutrients and helps hold moisture.
- Clear the area of debris
- Loosen soil to 8 inches deep
- Mix in 2 inches of compost
- Rake smooth before planting
Water Correctly
August can be dry. New plants need consistent water. Water deeply in the morning. This reduces evaporation and disease.
- Water at the base, not on leaves
- Use soaker hoses for efficiency
- Check soil moisture daily
- Mulch to retain moisture
Choose The Right Location
Most fall flowers need full sun. Some tolerate partial shade. Read the plant tag. Place tall flowers in back, short ones in front.
Protect From Pests
Late summer pests include aphids and slugs. Check plants weekly. Use insecticidal soap for aphids. Set beer traps for slugs.
Benefits Of August Planting In Minnesota
Planting in August has advantages. The soil is warm, so roots grow fast. You get color in fall when other plants fade. Many flowers survive winter and return in spring.
August planting also fills gaps. If spring flowers died back, you can replace them. It keeps your garden looking good until snow.
Extended Bloom Time
Flowers planted in August often bloom into October. Some last until November if protected. This extends your gardening season by weeks.
Better Root Development
Warm soil encourages root growth. Cooler air reduces stress on plants. They establish faster than in spring heat.
Lower Water Needs
As September approaches, temperatures drop. You water less often. This saves time and money.
Common Mistakes When Planting In August
Avoid these errors to keep your flowers healthy.
- Planting too late in the month
- Not watering enough during hot spells
- Choosing flowers that need long growing seasons
- Forgetting to mulch
- Overcrowding plants
Planting too late means flowers may not bloom before frost. Check the average first frost date for your area. In northern Minnesota, it can be early September. In the south, late September or early October.
Flowers To Avoid In August
Some flowers need more time. Avoid these in August:
- Sunflowers (most varieties take 60+ days)
- Zinnias (need heat and time)
- Cosmos (slow to bloom from seed)
- Sweet peas (prefer cool spring)
- Lavender (needs full season to establish)
Stick with fast-growing or cold-tolerant types. The list above is your best bet.
Where To Buy Flowers For August Planting
Local garden centers have fall plants in August. Big box stores also carry mums and pansies. Farmers markets sometimes sell transplants. Online nurseries ship quickly.
Check plants for health. Look for green leaves and no pests. Avoid rootbound plants. They may struggle to establish.
Caring For August-Planted Flowers
After planting, care is simple. Water when dry. Fertilize lightly every two weeks. Remove dead flowers. Watch for frost warnings.
Frost Protection
Cover plants with cloth or plastic if frost is forecast. Remove covers in the morning. This protects blooms and extends the season.
Winter Preparation
Some flowers are perennials. Mulch them after the ground freezes. This insulates roots. Cut back dead foliage in spring.
Frequently Asked Questions
Can I Plant Flowers In August In Minnesota?
Yes, you can. Choose fast-growing or cold-tolerant flowers like marigolds, pansies, and mums. They will bloom before frost.
What Flowers Bloom In August In Minnesota?
Many flowers bloom in August, including coneflowers, black-eyed Susans, and phlox. For August planting, choose flowers that bloom in fall.
Is It Too Late To Plant Flowers In August?
No, it is not too late. You just need to pick the right varieties. Stick with flowers that mature in 30 to 60 days.
How Late Can I Plant Mums In Minnesota?
You can plant mums until mid-August. They need time to root before winter. Early planting gives best results.
Do I Need To Fertilize Flowers Planted In August?
Yes, light fertilization helps. Use a balanced fertilizer every two weeks. Stop fertilizing in September to let plants harden off.
Final Tips For August Flower Planting
Start with healthy plants. Water well after planting. Mulch to keep soil cool. Enjoy the color until snow flies.
August planting is a smart way to extend your garden. You get more blooms with less work. The best flowers to plant in August in Minnesota are the ones that thrive in cool weather. Give them a try this year.
Remember to check your local frost dates. Adjust planting times if needed. With the right choices, your garden will look great into autumn.
Do not forget to deadhead regularly. This keeps plants blooming longer. Also, remove any diseased leaves to prevent spread.
If you have extra space, try a few new varieties. You might find a new favorite. Gardening is about experimenting and learning.
One more thing: enjoy the process. August planting is relaxing. The weather is nicer than July. Take your time and have fun.
Your garden will thank you. Neighbors will notice. And you will have fresh flowers for indoor arrangements. It is a win-win.
So go ahead and plant. The best flowers to plant in August in Minnesota are waiting for you. Get them in the ground soon. You will be glad you did.