23 Native Seeds that Require Cold Stratification to Plant in Fall

My gardening education started with simple tasks like germinating seeds like sunflowers and lettuce. Even my young fingers could stick these seeds in the ground and watch them emerge a few days later.

As my interest in plants grew, I marveled at the wildflowers I noticed while hiking and learned about the benefits of native plants. But I also realized some of these plants had seeds that weren’t as easy to germinate as those of my childhood. That’s because they require a period of cold, moist stratification before native seeds can break dormancy.

While sticking the seeds in your refrigerator for a month or two is one option, you can also rely on nature. Planting the seeds outdoors in the fall allows them to be naturally exposed to cold, damp conditions over the winter. By the time spring arrives, cold stratification ensures that the native seeds will be ready to germinate.

Indian Paintbrush

Native to much of the Midwest and parts of the Mid-Atlantic, the Indian paintbrush stands out thanks to bright red bracts surrounding small green flowers. These plants grow as either annuals or biennials and prefer moderately moist soil. The bright crimson color typically appears in the spring, but plants may also produce flowers in the fall.

You’ll often see Indian paintbrush growing in meadows as well as open areas in forests. The plants prefer moderately moist soil but can tolerate brief dry spells.

Indian paintbrush is a hemiparasitic plant, which means the roots rely on other living plants for nutrition. If you’re starting seeds, you’ll need to plant them on a host plant like blue gramma, buffalo grass, and Pennsylvania sedge. Cut a slit in the host plant’s base, then sow the seeds near the cut.

Fireweed

Fireweed is native to much of the northern and western United States, all the way from Maine across to Washington and down to Arizona. The perennials send up red stems covered with slender, willow-like leaves. During the hottest days of summer, it sends up clusters of vibrant, bright pink flowers.

You can find fireweed growing in areas recently disturbed by fires, hence its common name. However, it also grows in other open sites like roadsides, meadows, and stream edges.

If you want to plant it at home, be aware its rhizomes can lead it to quickly spread. Since fireweed doesn’t handle competition well, neighboring low-lying plants will limit its growth.

Blue Mistflower

With light purple flowers covered with small, floss-like threads, the native mistflower closely resembles the garden-grown ageratum. However, this plant belongs to an entirely different species. It’s also a hardy perennial, while ageratum is an annual.

This plant is native to the majority of the southeast quarter of the United States, all the way from Maryland to Texas. You can often spot the plants growing in areas that remain slightly moist throughout the summer. If you want to grow mistflower at home, water the plants during summer droughts.

Allow this native species to naturally undergo cold stratification by placing the tiny seeds on top of the soil. Avoid covering them. After the weather warms in the spring, they’ll start to germinate. If you find you have more seedlings than you’d like, you can always thin out excess plants.

Wood Anemone

You can often find these perennials growing along the forest floor in mountainous areas of the eastern U.S. They have cute leaves with serrated margins and send up white blossoms in the spring. The delicate blooms have five white sepals that resemble petals.

Native wood anemone seeds require a double stratification (cold then warm) before they will germinate. That means they must undergo a cold, moist period followed by a warm period and then another cool, moist period. Therefore, if you plant the seeds outdoors in the fall, don’t expect them to germinate until a year and a half later.

Rattlesnake Master

While you can find many native plants with clusters of colorful blooms, rattlesnake master is truly unique. The perennials produce long, slender leaves edged in tiny spikes. In the summer, they send up a thick stalk topped with a branching cluster of round flowers that look like tiny disco balls.

The plants are native to most of the eastern United States, with the exception of New England. Some people believe the common name comes from the resemblance to a rattlesnake tail, but it actually dates back to incorrect beliefs that the plant could treat rattlesnake bites. 

The plants prefer soil that remains moderately moist, but they aren’t picky about soil type. Established plants survive drought easily. Since they look so different from other plants, they add an interesting contrast when grown with natives like Rudbeckia, boneset, and Coreopsis.

White Snakeroot

This snakeroot is a flowering perennial native to much of the eastern United States. You can often see it growing in mixed meadows, alongside roads, and near forest edges. It grows well in many soil types as long as the ground isn’t too wet or too dry.

Each plant forms a tall stalk with ovate leaves arranged along the stem. The stem branches near the top of the plant and forms clusters of buds that turn into white blooms in the late summer. Each flower has elongated stamens, giving it a slightly hairy appearance.

The seeds of this native plant require at least sixty days of cold, moist stratification before they can germinate. You can either sprinkle the tiny seeds on the soil surface or sow them in a container that you leave outside over winter.

Harbell

A type of perennial bellflower, harebell is native to much of the northern United States and part of the Southwest. The plants can tolerate poor, dry soil, and you can often find them growing in the crevices in rock walls or in rocky soil. However, they can also grow well in rich, open meadows.

The plants begin their lives by producing rounded basal leaves. During the early spring, the plants send up slender wiry stems covered with skinny leaves. Eventually, purple, bell-shaped flowers appear on the tops of the stalks. The plants often bloom for multiple months, especially if you remove the dead flowers.

When you plant the small seeds, leave them on top of the soil rather than covering them. The plants only require six-inch spacing, so you can leave the seedlings quite close together.

Joe Pye Weed

This flowering perennial produces tall, thick stalks that support the plant as it grows to six feet tall. In the late summer, the top of each stalk branches to form clusters of light pink blossoms. These blooms become covered with pollinators such as bumblebees, skippers, and butterflies.

Joe Pye weed grows best in moist soil, so don’t plant it in an area that remains dry throughout the summer. Although you can irrigate to keep the perennials moist, consider planting them beside a stream or in a damp, low-lying area. Just make sure it receives at least six hours of light a day.

Since the seeds are so small, there’s no need to cover them with soil. Just sprinkle them on the ground and wait until they germinate in the spring.

Rough Blazing Star

Also known as button blazing star, this member of the Liatris genus is native to much of the eastern half of the U.S. It prefers medium to dry soil and full sun, but it can tolerate a few hours of shade. It can tolerate poor, rocky soil and doesn’t mind drought.

They grow in clumps of tall stems covered in elongated leaves. During the middle of summer, bright purple flowers appear on the tops of the stalks. Each ‘flower’ is composed of many elongated disk flowers, leading to a hairy appearance.

Cardinal Flower

Cardinal flower is a short-lived perennial that thrives in moist, rich areas. You can often see it growing in and around streams and near low-lying forest areas. Although the plants don’t live for more than a few years, they reliably self-seed.

The plants produce tall, upright stems with elongated leaves. In midsummer, they produce bright red flowers with three lower petals and two upper petals. Butterflies, hummingbirds, and bees flock to the flowers to feed on their sweet nectar.

The seeds of this native species don’t require cold stratification, but they benefit from it. A few weeks of cold, moist exposure helps, but ensure your seeds are exposed to light as they germinate.

Virginia Bluebells

These spring ephemerals only stay around for a couple of months, but their spectacular clusters of bell-shaped blooms make them worth planting. The flowers start out light pink and turn to shades of deep blue as they mature. You can sometimes see large colonies of these beautiful blue blooms blanketing moist forests and stream edges.

If you want to grow them at home, choose an area with moist, rich soil. A woodland is ideal, but you may be able to grow them in a shaded garden. Enriching the soil with compost before planting will help the plants thrive.

Their small seeds can be difficult to germinate. The best option is to direct sow them in the soil in the fall so they can spend the winter outdoors. Check for seedlings in the spring and make sure the soil remains moist if a spring dry spell arrives.

Stiff Goldenrod

Like all goldenrod species, stiff goldenrod produces yellow spikes in the late summer and fall. This species produces branching clusters that are larger and flatter than many other types of goldenrod. It’s native to the central third of the United States.

The stems are straight and rigid, leading to the common name. They are covered with small, ovular leaves that turn beautiful shades of red in the fall.

Goldenrod species vary in their moisture preferences, but stiff goldenrod can tolerate anything but soaking-wet soil. The plants often self-seed, so don’t be surprised if they spread in a few years.

Purple Passion Flower

Although it looks like it belongs in the tropics, purple passion flower is native to much of the southeast United States. The vining species happily grows along the ground, but its tendrils also allow it to grow up fences and arbors. It produces leaves with three distinct lobes.

During the summer, the plants produce unique purple blooms. Each flower is two to three inches wide and features wavy, hair-like sepals and showy, raised pistils and stamens. The flowers give way to round fruits that start out firm and green before ripening into soft, yellow or orange fruits. The fruits are filled with seeds covered in an edible sweet and sour gel.

The flowers are visited by many pollinators, and the vines are hosts for caterpillars, including those of the gulf fritillary and variegated fritillary. If you plant these vines at home, be aware they spread by root suckers. Also note that these native seeds don’t require cold stratification but benefit from cold exposure and some scarification as well.

Wild Blue Phlox

Also known as woodland phlox or blue phlox, this species produces five-petaled flowers that closely resemble those of other phlox species. Wild blue phlox produces stems that grow along the ground and send up smaller, branching stems. Clusters of light blue, purple, or pink flowers appear in the spring and early summer.

This species grows well in rich soil found near woodland edges, but it can also grow in rocky areas. They prefer soil that’s moderately moist.

If you keep the seeds at home, store them in a cold area, such as your refrigerator. Planting them outdoors in the fall will allow them to receive a natural period of stratification so they can germinate more prolifically the following spring.

Obedient Plant

This member of the mint family produces tall stems covered in lanceolate leaves. In the late summer, they produce tall flower spikes covered with tubular flowers. The blooms range in color from light pink to fuchsia and open from the bottom to the top. If you bend the flower stalks, they’ll remain in position, hence the name obedient plant.

The plants spread via underground stems called stolons and can quickly colonize an area. Therefore, they’re a great option for covering bare areas. Since they’re native to most areas east of the Mississippi, they have a wide planting range. Just be aware they prefer moderately moist soil and won’t thrive in drought.

Great Blue Lobelia

Great blue lobelia is a short-lived perennial that flowers in summer and fall. The plants often form large colonies, but you can also find single plants. Although the plants don’t live for more than a few years, they often self-seed.

The plants begin sending up tall flower stalks in the summer, and flowers often appear in July or August. The purplish-blue tubular flowers feature three distinct lower petals and two upper petals. Depending on the conditions, the blooms will remain through the middle of the fall.

These plants prefer moist to wet soil. Try planting them near pond edges, in low-lying areas, or in moist forest edges. You don’t have to use cold stratification for these native seeds, but it will promote higher germination rates. Make sure you’ve exposed seeds to light, as this is required.

Nodding Onion

Nodding onion produces spherical flower heads made up of tiny purple or white flowers. While many alliums produce similar flowers, this species differs from others due to its drooping or nodding flower heads.

The plants grow well in a variety of soil types with moderate moisture. You can find it growing on exposed rocks, open meadows, and moist forest edges. They can spread by self-seeding and producing bulb offsets.

Cup Plant

Cup plants are flowering perennials native to the Midwest and surrounding states. However, they’re sometimes viewed as noxious weeds in areas outside of their native range. Therefore, you should complete some more research before adding them to your garden.

The plants get their name from their upturned leaves that hold water and serve as drinking spots for birds and insects. In the summer, they send up tall flower stalks topped with yellow, daisy-like flowers. These flowers provide nectar and pollen for insects and later seeds for birds.

The plants grow well in average soil with medium moisture, but they can also tolerate heavy, wet soil. Just be aware the plants can spread and outcompete smaller plants.

Common Blue-Eyed Grass

Don’t let their common name and long, slender leaves fool you—these plants aren’t true grasses. Instead, they’re members of the iris family. The plants remain short but their rhizomes allow them to easily form large clusters. That means they’re great plants for filling in empty patches between plants or stones.

During the late spring and early summer, small, light blue and yellow flowers appear near the tops of their leaves. The flowers open each morning and close by the evening, so keep a close eye on them to catch their beauty.

Common blue-eyed grass is native to areas east of the Mississippi River from Michigan down to east Texas. They prefer moderately dry soil but can handle moist periods.

White Meadowsweet

White meadowsweet is a wonderful native alternative to the often-planted Japanese spirea. These flowering shrubs are native to the Northeast and Midwest, all the way from Maine to North Dakota. They grow well in moderately moist soil and can tolerate dappled light as well as morning or afternoon shade.

The plants produce numerous unbranching stems from their base. Over time, the stems develop a weeping form as they bend towards the ground. In the summer, they develop tight clusters of small white flowers near the end of their branches.

If you’re interested in a spiraea that’s native to the Southeast, check out Virginia meadowsweet (Spiraea virginiana). Both meadsweet species produce small seeds that require multiple months of cold stratification, so they’re great candidates for fall sowing.

New England Aster

This aster is an iconic fall plant throughout much of the United States, including areas outside of New England. Like most asters, it’s a late bloomer. Its bright purple and yellow flowers appear as early as August and often remain around until the first fall frost.

It isn’t picky about soil type and can grow well in wet and moderately dry soil. Just don’t be alarmed if the lower leaves turn brown and crisp when the plant is blooming. And if you want the plants to grow bushy rather than tall, prune the tops during the spring.

Before the flowers appear, you can differentiate New England asters from similar plants by their foliage. The leaves’ lobes almost encircle the slightly hairy stem.

Common Ironweed

When late summer arrives, fields and forest edges across the Midwest become awash with bright purple ironweed blooms. The flowers appear in branching clusters set atop long, thick stems. Along with attracting all kinds of pollinators, this plant is also a host for the American painted lady butterfly.

This ironweed species prefers moderately moist to wet soil, so it happily grows alongside streams and rivers as well as in low-lying areas that remain moist. You can also plant it in drier areas of your garden as long as you provide supplemental moisture during dry periods.

If you don’t live in the Midwest, you may be able to find other ironweed species native to your area. Tall ironweed (Veronia gigantea) is native to many areas east of the Mississippi, and western ironweed (Vernonia baldwinii) is native to Texas, Oklahoma, and other south-central states.

Wild Geranium

The wild geranium is a spring-blooming perennial that’s native to the eastern United States. It has beautiful, deeply dissected leaves and sends up slender flower stalks topped with delicate pink or purple flowers. The flowers turn into slender seed pods that shoot their mature seeds into the surrounding environment.