Why You Should Sow Wildflower Seeds This Winter
Would it surprise you to hear that winter is a good time to sow wildflower seeds? Although we usually plant annual flower and vegetable seeds from spring through fall, many perennial wildflower seeds need pre-chilling, or a period of exposure to cold and moisture. These seeds can be scattered even on top of a blanket of snow.
Ideally, you’ll winter-sow your wildflower seeds over ground that you’ve already prepared, says David Salman, founder and Chief Horticulturist at High Country Gardens in Santa Fe, New Mexico. He recommends raking the ground before snow and ice arrive to remove any debris and expose the ground. “If the area is unplanted and bare soil,” he says, “use a bow rake to create shallow furrows.”
Butterfly Milkweed (Asclepias tuberosa) Found throughout the U.S.
This favorite of the monarch butterfly is actually fighting an evolutionary war. Butterfly milkweed is full of toxins, which monarch larvae ingest and absorb in order to become poisonous themselves. But the milkweed doesn’t want to be eaten — so it secretes a thick latex that gums up the mouthparts of the larvae. Not to be outdone, the larvae cut notches in the leaves to slow the flow of latex while they eat. The result? A delicate balance that allows both to survive. (Thanks to Andrea DeLong-Amaya/Lady Bird Johnson Wildflower Center and Kris Light/East Tennessee Wildflowers, for their help.)
Painted Trillium (Trillium undulatum) Found throughout the eastern U.S.
Trilliums, also called “wake-robins” because of their spring bloom time, are the subjects of eager treasure hunts by wildflower enthusiasts who consider its perfect three-part form a sight to behold. But if you happen across one of these beauties in the woods, don’t pick it; its survival is threatened in some areas.
Eryngo (Eryngium leavenworthii) Found in the south central U.S.
Take a closer look at the intricate, alien-looking eryngo and then guess which plant family it belongs to. Did you guess thistle? Nope. Eryngo is actually a cousin of parsley and carrots, believe it or not, and the roots of certain varieties were once candied and eaten as an aphrodisiac. This purple-blue wildflower is a gorgeous addition to cut-flower arrangements.
Chocolate Daisy (Berlandiera lyrata) Found in the south central and southwest U.S.
This flower is named for its heavenly cocoa-licious scent. “Get downwind of a stand of them on a warm breezy day and it’s pretty nice indeed,” says Andrea DeLong-Amaya, director of horticulture at the Lady Bird Johnson Wildflower Center in Austin, Texas. “They’re also great for attracting pollinators.” Like many plants that grow in warm climates, chocolate daisy sports hairy silver foliage that reflects heat.
Bitterweed (Helenium amarum) Found in California, central and eastern U.S.
Bitterweed is a beautiful yellow flower with an ugly name — but it comes by its reputation honestly. When cows eat its foliage, it makes their milk turn bitter. (And if they eat too much, it’s hooves up.) Bitterweed makes a glorious presentation in an open field: here, it shines among bluebonnets underneath a majestic live oak.
Carolina Jessamine (Gelsemium sempervirens) Found in southeastern U.S.
This tenacious Southern climber makes quite a show on tree trunks and telephone poles, where its tough stems give it its nickname, “poor man’s rope.” Carolina jessamine smells divine, but admire it from a distance, as every part of it is highly toxic.
Long-Spurred Violet (Viola rostrata) Found in the eastern U.S.
This native violet, which thrives in rich woodland soil, is easily identified by the elongated spurs behind its nodding flower heads. This demure habit of nodding is why violets are considered a symbol of modesty; their petals often droop so low that they’re hidden behind the leaves.
Agarita (Mahonia trifoliolata) Found in Arizona, New Mexico and Texas
This thorny little plant is sometimes called “babysitter bush” because birds and other wildlife like to nest inside for protection. Its beautiful honey-scented flowers arrive in early spring, but when May comes, the bright-red fruit is the star. To avoid the spines, put a sheet underneath and whack the plant with a stick so that the ripest fruits fall to the ground. They make a sweet juice that’s delicious straight up or in your favorite margarita.
Native Wisteria (Wisteria frutescens) Found in the eastern and south central U.S.
In Buddhism, the wisteria bloom represents humility, so it’s ironic how brazenly the vines will take over your garden. But it’s Chinese wisteria (Wisteria sinensis) that causes all the headaches. Native American wisteria, on the other hand, is just as beautiful but grows less aggressively. Look for it at native plant nurseries near you.
Creek Plum (Prunus rivularis) Found in the south central U.S.
January on the Chinese flower calendar is the month of the plum blossom, which is a symbol of beauty. If you’ve ever spotted a creek plum blossom coated with dew, it’s easy to see why. This native shrub is worth seeking out along creekbeds and canyons in Texas and Oklahoma — the fruit is delicious picked fresh.
Texas Bluebonnet (Lupinus texensis) Found in Texas
Fields of Texas bluebonnets are an American icon. But what they really represent is turmoil — as a fast-colonizing annual, bluebonnets tend to pop up where soil has been recently disturbed: overgrazed pastures, new developments and flooded creek beds. There, they fix nitrogen in the soil and make it hospitable to other annuals and perennials. Bluebonnets are soon overtaken by these new plants and disappear . . . only to reappear somewhere else they’re needed.
Wild Poinsettia (Euphorbia cyathophora) Found throughout the southeastern, central and southwestern U.S.
This isn’t your Grandma’s foil-wrapped Christmas gift. “Most people don’t realize we have a native poinsettia,” DeLong-Amaya says. “That’s probably because as a cold-tender annual, this plant is toast by the time the holidays arrive.” The wild variety is a subtle and delicate beauty that expires with the first frost and reappears from seed in spring.
Passionflower (Passiflora incarnata) Found in eastern and central U.S.
An unusual bloom found on a rapidly growing vine, passionflower has traditional medical use as a sedative. But it’s more famous for its Christian symbolism. Its name comes from the suffering (passion) of Jesus, not from amore: its petals represent the ten faithful biblical apostles, minus Peter and Judas because they betrayed their master. The corona is said to look like Christ’s crown of thorns, and the five stamens like his five wounds. So said America’s first Jesuit explorers, anyway, who thought the flowers were a sign from God.
Datura/Jimsonweed/Angel Trumpet (Datura wrightii) Found throughout most of the U.S.
Datura is, um, quite a trip. One of this flower’s common names, jimsonweed, comes from “Jamestown weed” — a reference to Revolutionary War soldiers who foraged this plant for food and suffered wild hallucinations. Also used in manhood iniation rites among American Indian tribes, this plant has potent narcotic qualities, so don’t sample it at home. But do consider adding it to your garden, where its night-opening blooms attract sphinx moths and other pollinators.
Spineless Prickly Pear (Opuntia ellisiana) Found in Texas
This native cactus (shown at top) makes for good eating. The pads can be fried, steamed or sauteed, and the fruits, called tunas, are processed into jellies and juice. But prickly pear was once an important dye source — not made from the plant itself, but from the cochineal insects it attracted, whose insides are bright magenta. Cochineal dye is still used as a colorant. “I saw cochineal listed as an ingredient in an energy drink,” DeLong-Amaya says. “I wonder how many people know they’re drinking bug guts.”
Maximilian Sunflower (Helianthus maximiliani) Found throughout most of the U.S.
Perennial native sunflowers, such as this Maximilian sunflower that grows up to ten feet tall, were once revered by Incas as icons of their sun god. Their seeds were considered sacred by certain Plains cultures — and still are by many birds — and were left on gravesites to nourish the dead on their way to the Happy Hunting Grounds.
Fall Aster (Symphyotrichum oblongifolium) Found across the eastern and central U.S.
Asters are the stars of the autumn wildflower landscape — and their name actually comes from the Greek word for “star.” Ancients thought they were enchanted flowers, sacred to the gods, and used them in various ways to ward off evil. Best these days to use them to attract pollinators, as they’re hands-down favorites of bees and butterflies.
Purple Coneflower (Echinacea purpurea) Found in the central and eastern U.S.
When it’s not serving as a footstool for swallowtails or lending a graceful note to prairie gardens, this chemical-laden flower is being used to treat everything from the common cold to hemorrhoids. The name Echinacea is a reference to the prickly central cone; it comes from the Greek echinops, meaning “hedgehog.”
Cardinal Flower (Lobelia cardinalis) Found throughout the U.S. except the Northwest
The American naturalist John Burroughs once said of cardinal flower, “It is not so much something colored as it is color itself.” This stunner haunts moist, shady woodland areas and attracts hummingbirds for miles around. Maybe that intoxicating quality is what inspired early native Americans to make love potions from its roots.
Goldenrod (Solidago spp.) Found throughout the U.S.
Stop blaming goldenrod when you sneeze. This delightful wildflower makes hillsides look like impressionist paintings in late summer and early fall, but is maligned because it blooms at the same time as ragweed (a dull, hardly noticeable flower). Ragweed pollen is what mucks up your sinuses; goldenrod pollen is made to be carried by bees and butterflies, not wind. It’s too heavy to stay airborne.
“Before sowing, I like to mix my seeds with sand in a bucket to help more evenly distribute the seeds. I also mix a handful of mycorrhizal spore granules into the seed and sand mix.” He suggests using a mycorrhizal product to improve germination and seedling survival.
“After the seed/sand/mycorrhizal mix is sown,” Salman says, “turn the bow rake over the soil to smooth the shallow furrows and lightly cover the seeds with soil. A light mulch of clean wheat or barley straw will improve germination."
The seeds will eventually drop down into the snow as the temperatures rise and then fall again. That happens because the ice underneath the soil starts to melt when the mercury rises. When the weather gets cold again, the ice re-forms. As the ground alternates between thawing and freezing, it may crack or move up and down. Even if this movement is almost imperceptible, the seeds will gradually work their way through the snow and contact the ground.
Salman says that gardeners who get snow by December can start sowing them and continue into February, and should have enough snow cover for their wildflower seeds to germinate.
DIY Seed Bombs 01:01
Of course, if you live where the winters are very mild, such as in California, Florida and south Texas, you can sow wildflower seeds outdoors at almost any time of the year, avoiding only the hottest, driest part of summer.
If you live where the winter temperatures drop to freezing or below, but you don’t get snow, you can still winter-sow your wildflower seeds. Just scatter them while you’re still getting frosts in late winter or early spring, Salman says. “After sowing, cover the seeds lightly with clean wheat or barley straw to keep them moist and hide them from the birds.” This will also help keep them from being blown away by the wind.
Salman says if you’re using a wildflower seed mix that contains non-frost hardy annuals, such as zinnias and marigolds, you’ll need to sow when the spring temperatures are reliably warm and all danger of frost has passed. On the other hand, “If your mix contains frost-hardy annuals, the annuals will wait to germinate when temperatures are right for them, even when sown in winter.”
Because there are so many different seed mixes available, be sure to look for one that is especially designed for your region. You can mix your own seeds, too; simply choose wildflowers that will thrive in the growing conditions you can provide.
Some gardeners practice a different kind of winter sowing, by planting vegetable and flower seeds in clear plastic containers during the winter, and leaving them outside to sprout. When the seedlings become big enough and are hardened off, they’re transplanted into the garden.
But, Salman says, “The whole point of (winter sowing) wildflower seed mixes is to avoid having to transplant seedlings as this is highly labor intensive. Seed is relatively inexpensive and we should sow many more seeds than will reasonably germinate. This is how nature does it; release a million seeds and get one hundred plants.”
With good preparation, he adds, gardeners will increase the survival rate of their winter-sown wildflower seeds considerably and have plenty of vibrant, beautiful blossoms to enjoy by spring and summer.