Verbesina virginica
A valuable nectar source for many pollinators such as butterflies and bees, frostweed is a common southeast Texas native plant that may be overlooked until it bursts into profusion this time of year. Frostweed blooms from September to November, providing a nectar to Monarch butterflies as they migrate south to their historic wintering location in Mexico, along with local insects looking to fortify themselves for winter. If a hard freeze does not occur in late fall, frostweed will continue to bloom and nourish a myriad of beneficial bugs into December.
This stately plant has showy, white blossoms, substantial leaves, and stems enhanced by green flanges down their length. Valuable to pollinators in many ways, frostweed is a food source, or host plant, for caterpillars of Summer Azure, Bordered Patch, and Silvery Checkerspot butterflies. Frostweed is of special value to native bees and European honeybees because of the abundance of nectar provided by this amazing pollinator plant.
If you love a beautiful flowering garden but feel you lack a green thumb, frostweed is still a perfect choice! This hassle-free plant thrives in the partly shaded edges of wooded areas, growing well in almost any type of soil and requiring very little maintenance. No serious pests or diseases affect frostweed, and it is highly resistant to deer. In addition, established plants can withstand dry periods without supplemental irrigation and do not need fertilization. In our plant-hardiness zone 9b, frostweed is a perennial, spreading by the growth of underground stems that sprout new plants as temperatures warm. To start growing your own frostweed, plant transplants now or sow seeds after the last frost of the spring.
The common name “frostweed” refers to the plant’s most outstanding characteristic: ice crystal formations, called frost flowers, caused by stem ruptures in freezing weather. Frost flowers form only when the air temperatures are freezing but the ground is warm enough for the plant’s root system to remain active. Plant juices flow upward into the stem, where the cold air freezes them, rupturing the cell walls. The ice crystals then push their way out of the stem to form ribbons or wavy sheets of ice along the length, creating fascinating frost flowers.
With a little bit of hunting, you can find frostweed at a local native plant nursery near you – or check out Master Gardener or Native Plant Society chapter sales. Frostweed is a ready re-seeder, so any friend with this prolific plant is bound to have seeds or starts to share! Collecting dried seed heads or seeking out an online source for native Texas seeds are also good options. You’ll not only be rewarded with a stately plant that blooms when some other parts of the garden are past their prime but also a bounty of beneficial insects, travelling monarchs, bees and butterflies!
For more details about this spectacular fall bloomer and other native plants, visit the Lady Bird Johnson Wildflower Center Plant Finder.
To learn more about the fascinating formation of frost flowers, visit the Plant Resource Center, Flora of Texas’s page on Crystallofolia.
