It may seem a bit strange to be writing about starting a butterfly garden in winter, but this is the best time to start those seeds. Really!
If you live in the south where it never freezes sowing milkweed seeds and native perennial seeds in the winter will give you a helpful head start to a beautiful growing season. But even those of you who live where it freezes in the wintertime can start your seeds in the depth of winter by using the winter sow method.
And if you just want to wait until spring to start seeds, you will still need to prepare those seeds now. Most perennial plant seeds such as native milkweed and native wildflowers require a combination of cold and damp to germinate. Cold stratification, also known as seed stratification, is the process of exposing seeds to cold and moist conditions to encourage germination. In nature, the stratification process takes place when fallen seeds overwinter underground or beneath a layer of snow. But you can accomplish the process yourself by replicating Mother Nature.
How to Stratify Seeds in the Refrigerator
Follow these steps to cold stratify your seeds in the fridge.
1. Place the seeds in a damp medium. Seeds can be sprinkled onto a damp paper towel or can be placed in a moist medium such as peat moss, sand, or vermiculite. Ensure that the medium is moist but not soaking wet.
2. Store the moist seeds in a plastic bag. Once your seeds are wrapped in a damp paper towel or planted in a moist growing medium, place them in a plastic bag. Be sure to label the bag with the name of the seeds and the date.
3. Place the bag in the fridge. The time you need to keep your seeds in the refrigerator depends on the variety, but 4-6 weeks should be enough time for most seed varieties. After the recommended days of cold moist stratification are done, you can direct sow the seeds outside in the spring after the last frost under a very light amount of soil or you can start them in containers with soil. The simple, quick process of cold stratification helps the seed germinate quicker and grow more readily in your garden bed.
Have you ever wondered how butterflies survive the cold snows and bitter winds of winter? Most people are familiar with the amazing, long migration of the Monarch butterflies to Mexico to escape the cold, but many species of butterflies hunker down for the winter in your backyard. “The great majority of butterflies stay where they are. They spend the winter where they spend the summer,” says Jeffrey Glassberg, biologist, author and president of the North American Butterfly Association.
Among the approximately 700 species of North American butterflies there are three main strategies that have evolved for winter survival. The first involves diapause, either as an egg, a caterpillar, or as a chrysalis. Hibernation in the adult form is the second strategy. The third and final solution is simply to head south.
Most butterflies spend the winter months in a condition called diapause. Diapause is a period of suspended growth or development at a particular stage in the life cycle, to protect butterflies from long periods of inclement weather. Onset of diapause is stimulated by reduced daylight hours. Each species that enters diapause will do so in a different life stage: egg, larva, pupa, or adult.
Many species spend the winter as caterpillars such as the Tawny Emperor, Hackberry Emperor, Viceroy, Red-spotted Purple, and many other species. They create a nest out of leaves and wait until spring to emerge. These nests are called hibernacula (singular = hibernaculum). When spring arrives with longer days and new leaves on their trees, they emerge and begin eating and growing again.
In the winter, the trees will drop their leaves. Caterpillars that overwinter will instinctively first sew their chosen leaves to the twig. Some species simply sew several leaves together or fold one leaf and stay inside during the winter. Some species, such as Tawny Emperors, will change color from green to brown inside their hibernaculum. Brown caterpillars inside brown leaves would be extremely difficult to see.
Swallowtail butterflies spend the winter as chrysalides. Just before they pupate, the longer nights and cooler temperatures will trigger the caterpillar to become a chrysalis and go into diapause. When it starts to warm up in the spring, the swallowtail will emerge from the chrysalis.
Butterflies who spend the winter in chrysalis find a sheltered place like overhangs or deep shrubbery. The chrysalis, like the adult and caterpillar, stops development over the winter months and contains special chemicals to keep from freezing. When the warmer weather returns and the days lengthen, development resumes in the chrysalis and the adult butterfly emerges in time for fresh blooms on nectar plants.
Perhaps the most vulnerable species are those who spend the winter as eggs, usually laid in late fall in the leaf litter at the base of the host plant. These eggs will hatch in the spring when the host plant has put on new growth.
Butterflies that remain in cold-winter areas as adults find safe places to rest, like tucked into crevices, under or in between logs or underneath loose bark on trees and then will enter into diapause. The butterflies shut down all their non-essential systems like reproduction and slow their metabolism dramatically. Special chemicals in their bodies work as anti-freeze, and the butterfly remains dormant until warmer weather arrives. These species, particularly the Mourning Cloak, often can be seen flying on the early days of spring, and occasionally even during warm spells in January or February.
Some butterflies, such as the Monarch butterfly, migrate to warmer climates or travel to overwintering sites. They cannot survive freezing temperatures. Monarchs that overwinter in Mexico and California during the overwintering period (approx. October-March) are usually in reproductive diapause, which means they stop mating and laying eggs.
Many other species migrate to warmer climates for the winter and continue their normal lifecycle pairing and laying eggs, during the winter. Their offspring migrate back in the spring. The Painted Lady is known for its migratory behavior here in the United States as well as its epic migration between Europe and Africa.
You can help a butterfly survive winter, no matter how they do it, with a few simple actions:
Leave the leaves! Leaf litter helps replenish soil nutrients and provides overwintering habitat for a number of beneficial invertebrates. If you can’t leave leaves throughout the yard, consider creating a leaf pile or adding leaves to compost. Ditch the fall garden cleanup. Besides leaving leaves, consider leaving standing flower and grass stalks in your garden. Sometimes, these stalks harbor chrysalises or pupal cases from local insects like native bees. These areas also provide winter shelter and food for birds. Remove plants in the spring. Generally, by the time the grass needs its first cut in the spring, the pollinators have emerged. Sow seeds and plan out next year’s garden. Butterflies not only need nectar plants to feed on as adults, but they need host plants for their young caterpillars to feed on as well. Winter is the best time to start planning and preparing your garden for spring and summer butterflies.
Monarch butterflies are known for their incredible, long-distance migration from as far north as Canada to their wintering grounds in Central Mexico. But did you know that not all monarchs over-winter in Mexico?
Monarchs living west of the Rocky Mountain range in North America overwinter in California along the Pacific coast near Santa Cruz and San Diego. Here microclimatic conditions are very similar to that in central Mexico. Monarchs roost in eucalyptus, Monterey pines, and Monterey cypresses in California.
Every Thanksgiving and New Years the Xerces Society along with hundreds of volunteers count the number of monarch butterflies at overwintering sites in the West.
The South Carolina coast is also home to a winter population of monarch butterflies, according to a recently published study published by South Carolina Department of Natural Resources (SCDNR). The research indicates that the insects live year-round in South Carolina, relying on swamps in the spring, summer, and fall and sea islands in the winter.
And then there is Florida! Because of the warm climate and continuous availability of host plants, much of Florida’s monarch population stays in the state year-round and breeds continuously throughout the year. Year-round residents are more common in southern Florida, as cold winter temperatures in northern Florida can kill monarchs at any life stage.
In addition to resident populations, the state also hosts migratory monarchs from northeastern North America, but there are competing hypotheses regarding how these migrants travel to, from, or through Florida.
When I lived in Central Florida I observed that monarch populations increased in late November. According to Dr. Karen Oberhauser, Florida is a terminal destination for migrating monarchs from the northeastern United States and southeastern Canada. These monarchs fly into Florida but don’t disperse out, making the Florida population a “sink population.”
Wherever monarchs are this winter, we can help these iconic butterflies by creating habitat for them in our own back yards.
Most of us are very familiar with the monarch migration this time of year. But did you know that monarchs are not the only butterflies that migrate? In fact, there is a butterfly that migrates even farther distances than the monarch.
The Painted Lady (Vanessa cardui), boasts the world’s farthest known butterfly migratory route, undertaking a phenomenal 9,000-mile round trip from tropical Africa to the Arctic Circle.
As one of the most cosmopolitan insect species in the world, the Painted Lady is found in all continents except Antarctica and Australia. Some of the reasons for its widespread distribution include a wide variety of plants it feeds and lays eggs on, the ability to migrate to avoid winter, and continuously reproducing.
Painted Lady larvae feed on an incredibly wide variety of host plants from many different families including thistles (Cirsium spp.), borage (Borago officinalis), hollyhock (Alcea rosea), mallow (Malva spp.), sunflower (Helianthus spp.), Plantain (Plantago spp.), and a few legumes including soybeans.
The Painted Lady is also known for its migratory behavior here in the United States. The butterflies will set off from their wintering grounds in the Mojave and Colorado deserts of southeastern California as winter gives way to spring. They travel roughly the same path every year, flying northwest to Sacramento in route to Oregon, Washington and beyond. (They’ve been spotted as far north as Alaska.) These migrations appear to be partially initiated by heavy winter rains in the desert where rainfall controls the growth of larval food plants.
In March 2019, after heavy rain produced an abundance of vegetation in the deserts, Southern California saw these butterflies migrating by the millions across the state.
Research on the Painted Ladies in North America is limited, but scientists believe they migrate to the southwestern United States and northwestern Mexico in the fall. They arrive in the desert in late fall and the cycle begins again.
One of the most interesting Painted Lady butterfly facts is that it can reach a speed of nearly 30 miles per hour, allowing it to travel up to 100 miles per day during its migration.
Some confuse these butterflies with the Monarch (Danaus plexippus). While their color scheme may be similar to Monarch butterflies, Painted Ladies have eyespots on the underside their wings in addition to brown coloring on both sides. Painted Ladies lack the vein pattern that Monarchs are best known for. Painted Ladies are also smaller than Monarchs, with a wingspan measuring less than 3 inches.
The Painted Lady breeds throughout the year. The female lays eggs during its migration, contributing to its global distribution. The butterfly undergoes metamorphosis as part of its life cycle that ranges from 1 month in subtropical areas to 2 months in the temperature zones.
Eggs are laid singly on plant leaves and develop over the course of 5 days, before the caterpillar hatches. Five larval stages, also known as instars, span over 25 days where the caterpillar feeds continuously and grows extensively, followed by a pupation stage when metamorphosis takes place. The adult butterfly emerges from the pupa after a week and finds a mate before settling on a leaf to lay eggs and start the cycle again.
Painted Ladies are one of the easiest butterflies to raise because not only will the young larvae feed on so many different host plants, they will also feed on a specially formulated artificial diet. This artificial diet makes it possible for the larvae to be sold in butterfly rearing kits and are often raised and studied in classrooms by elementary students.
According to Monarch Watch, Frostweed (Verbesina virginica) is a major fall-blooming nectar source for monarchs. By fall it’s usually at least three feet high and has dense clusters of snow-white flowers. Blooming typically coincides with peak migration.
The blossoms are also attractive to many other species of butterflies, bees, and other pollinators. It is the host plant for the Bordered Patch (Chlosyne lacinia) and the Silvery Checkerspot (Chlosyne nycteis) butterflies.
Native to the Southeastern United States and Texas, Frostweed is perennial throughout USDA zones 6-9. Reaching an average height and spread of about 3 feet, this plant is ideal for cottage gardens, background plantings in shady garden borders, or naturalized in wooded areas.
The name “Frostweed” is a reference to the plant’s tendency to excrete water from its stems in freezing weather, thus enhancing the winter landscape with the creation of interesting ice sculptures.Frostweed (Verbesina virginica) it is also known by other names includingWhite Crownbeard, Indian Tobacco, Iceplant, Iceweed, Richweed, Squaw Weed, White Wingstem, and Virginia Crownbeard.
Growing tips: Frostweed prefers dappled shade where it can form sizable colonies, like at the edge of a woodland or just under a large tree. Plant your Frostweed in a naturalized area where it can get dry to moist soil. It will grow from 2’-6’ tall with little to no maintenance, irrigation or pest control. If you plant it in a dryer and sunnier space you will tend to get smaller and more compact bushes with more flowers. You can also promote more fall blooms by cutting back the plant in mid-summer.