I used to think late summer was just a time for sweeping up dead leaves. Then I realized the secret to a spectacular spring starts in the dusty heat of August.
Sowing seeds now gives them a head start before winter.
Here is my list of what works.
Quick Summary
- 10 hardy annuals and biennials that handle winter cold.
- All establish roots in August to bloom early next spring.
- Best starter pick: Pansies & Violas — they tolerate extreme cold.
1. Pansies & Violas (Viola)
| Sun | Full sun to part shade |
| Water | Medium, consistent moisture |
| Height | 6–8 in (15–20 cm) |
| Bloom | Late winter to early summer |
| Zones | 4–9 |
Violas are outstanding in pots.
If you’re short on yard space, they’re easily one of the best flowers to grow in containers.
I started sowing these in late summer three years ago because I was tired of bare winter beds.
They sat under snow all winter, and then they exploded with color in February.
Tip: Keep the soil damp until germination. Violas do not like dry soil.
2. Calendula (Calendula officinalis)
| Sun | Full sun |
| Water | Low to medium |
| Height | 12–24 in (30–60 cm) |
| Bloom | Spring to frost |
| Zones | 5–11 |
Calendula is my absolute favorite for early spring salads and tea.
I sow them in August because the warm soil makes the seeds sprout in days.
They’ll grow a small cluster of leaves before winter, freeze solid, and then bloom weeks before spring-sown seeds.
If you want plants that continue sowing themselves year after year, I wrote a guide on my favorite self-seeding flowers that keep the garden going.
Care Note: Do not fertilize them too much. Rich soil makes them grow leaves instead of flowers.
3. Cornflower (Centaurea cyanus)
| Sun | Full sun |
| Water | Medium, well-drained |
| Height | 12–36 in (30–90 cm) |
| Bloom | Late spring to mid-summer |
| Zones | 2–11 |
Nothing beats that electric blue color in the spring.
Cornflower seeds need cool soil temperatures to keep growing, so sowing in late August is the perfect window.
They’ll spend the winter as a tiny rosette of fuzzy grey leaves.
In spring, they grow tall and start flowering almost overnight.
Warning: They grow so fast they can flop over. Plant them near sturdier plants for support.
4. California Poppy (Eschscholzia californica)
| Sun | Full sun |
| Water | Low, drought-tolerant |
| Height | 6–12 in (15–30 cm) |
| Bloom | Spring to summer |
| Zones | 6–10 |
I throw these seeds into the dry, gravelly patch next to my driveway.
They don’t like being moved, so direct sowing in August is the only way to go.
They’ll sit quietly through the winter rain and reward you with bright orange blooms in April.
Tip: Don’t cover the seeds with soil. They need light to germinate, so just press them into the dirt.
5. Love-in-a-Mist (Nigella damascena)
| Sun | Full sun to part shade |
| Water | Medium, well-drained |
| Height | 12–20 in (30–50 cm) |
| Bloom | Late spring to mid-summer |
| Zones | 2–10 |
The feathery foliage is beautiful even before the flowers open.
Nigella seeds sprout quickly in warm late summer soil, forming a soft green carpet that survives frosts.
I love them because they fill the awkward gap in early spring when other plants are still waking up.
Warning: They self-seed very easily. Cut the seed pods if you don’t want them spreading everywhere.
The plants that survive my forgetting to water are the ones I keep planting more of.
6. Forget-Me-Nots (Myosotis sylvatica)
| Sun | Part shade to full shade |
| Water | Medium, consistent moisture |
| Height | 6–12 in (15–30 cm) |
| Bloom | Mid-spring to early summer |
| Zones | 3–8 |
These are perfect if you’ve got trees blocking the sun.
I also keep a running list of other shade perennials that I love.
Sowing forget-me-nots in August allows the biennials to establish rosettes that will form a thick blue carpet next spring.
They prefer moist, cool soil, so I sow them in the shade of my hydrangeas.
Tip: Keep the area weeded. The tiny seedlings are easily crowded out in autumn.
7. Larkspur (Consolida ajacis)
| Sun | Full sun |
| Water | Medium, well-drained |
| Height | 24–48 in (60–120 cm) |
| Bloom | Late spring to summer |
| Zones | 2–10 |
Larkspur gives you those tall, cottage-style flower spikes that look like delphiniums but are much easier to grow.
Here is my secret trick for sowing them in August.
Put your seed packets in the refrigerator for two weeks before planting. They need that artificial cold shock to wake up when the soil is still warm.
Once planted, keep the soil cool by mulching lightly.
Warning: Every part of this plant is toxic. Keep it away from dogs that like to chew leaves.
8. Columbine (Aquilegia)
| Sun | Part shade to full shade |
| Water | Medium, well-drained |
| Height | 12–36 in (30–90 cm) |
| Bloom | Spring to early summer |
| Zones | 3–9 |
Columbine seeds are slow to sprout and require winter chill to break dormancy.
By sowing them in August, you let nature handle the cold treatment for you.
They’ll germinate in late autumn or early spring, growing into sturdy clumps that bloom by summer.
I find them much easier to start from seed outdoors than in trays on my windowsill.
Care Note: They like rich soil, so mix in some compost before sowing.
9. Snapdragons (Antirrhinum majus)
| Sun | Full sun to part shade |
| Water | Medium, well-drained |
| Height | 12–36 in (30–90 cm) |
| Bloom | Spring to frost |
| Zones | 7–10 |
In warm zones, snapdragons sown in August will grow slowly through autumn and winter.
They’ll put out huge flower spikes as soon as the weather warms up in spring.
I always plant them along the front pathway where their sweet scent catches the breeze.
Warning: In zones colder than 7, these will not survive the winter outdoors. Sow them in spring instead.
10. Siberian Wallflower (Erysimum cheiri)
| Sun | Full sun |
| Water | Low to medium |
| Height | 12–18 in (30–45 cm) |
| Bloom | Early spring to mid-summer |
| Zones | 5–9 |
Wallflowers produce clusters of bright orange and yellow blooms with a sweet, honey-like fragrance.
Sown in August, they establish quickly in the warm soil and develop deep root systems before the winter freeze.
They’re incredibly tough and thrive in poor, sandy soil where other plants struggle.
Tip: Pinch the growing tips of the young seedlings in autumn to encourage bushier growth in spring.
Common Questions
Will these seeds germinate in the hot August sun?
Yes, but you have to keep them damp. The main reason autumn sowings fail is that the soil dries out. Water them gently every morning.
Do I need to protect the young seedlings in winter?
No, these are hardy annuals and biennials. They’re designed to handle freezing temperatures. A light layer of leaves can help in very cold zones, but it is not required.
What if my seeds sprout and then it frosts early?
These plants form low rosettes that hug the ground. They are tough enough to survive early frosts without any issues.
What I Would Sow If I Only Had Room for One
If you only have space for one seed packet, make it California Poppies. They are cheap, grow in almost any soil, and that orange is the perfect spring welcome.
— Anh