And that has prompted several organizations to join forces to help make native milkweeds commercially available in Florida.
A number of organizations such as Monarch Watch and the North American Butterfly Association have launched a nationwide effort to plant milkweed, especially along the monarch's annual migration routes that start as far north as Canada and end in Mexico. The migration routes pass through Florida.
But it's not going to be easy.
Making more native varieties commercially available is the goal of a new project by a number of groups including the Florida Association of Native Nurseries, the Florida Wildflower Foundation and the Maguire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History.
“I'll order 50 to 60 of them, but the grower doesn't always have that many available. They take a long time to propagate, so the grower will only allow me to get so much,” she said.
With this mounting evidence of the detrimental effects of tropical milkweed, we have decided to only sell native species of milkweed. Unfortunately our growers are still working hard to build supplies of stock to meet demand. Though supplies are limited of native species, we have decided it is better to be without milkweed at some points than to sell a tropical milkweed plant. While it may feed your caterpillars in the short term, it is harmful to the species as a whole in the long term.
This free-flowering native milkweed usually only grows 12-24inches tall, continually sending up stalks topped with white blooms that often have a pink blush. They grow best in full sun with moist to wet soils – even growing directly in water! I’ve found them to be adaptable to quite a bit of shade and also average moisture and clay soils. The leaves provide substantial larval food for monarch and queen butterflies, and the constant flowers attract lots of adult butterflies as well as many other pollinators.
A pink-blooming native milkweed that gets big! It grows 4-6ft tall, providing the most amount of caterpillar food (of the native milkweeds) for monarch and queen butterflies. The plants regenerate leaf matter quickly during the growing season and have a short season of bloom in late summer – providing nectar-rich blooms for adult butterflies and other pollinators. They grow best in full sun with moist to wet soils, rich in organic matter. I have found this species to be adaptable in my yard in part sun with average moisture and clay soil amended with compost.
The red and yellow blooms of tropical milkweed are ubiquitous in North Florida butterfly gardens. This non-native milkweed has exploded in popularity as demand for milkweed grows to support declining monarch butterfly populations. This tropical species, native to Mexico, is very easy to propagate. Growers are able to quickly produce plant material of this species to meet the milkweed demand. It’s also very showy, blooming prolifically all season and regrowing quickly after being decimated by hungry caterpillars. But unlike our native milkweed species, the lush green foliage of tropical milkweed will stay up all winter if not killed back by frost – and that is a problem.
WHITE SWAMP MILKWEED
PINK SWAMP MILKWEED
Tropical milkweed has been an invasive species in Central and South Florida for a while now. The fast growth and prolific re-seeding of this species has remained unchecked by warm winters, resulting in large monocultures of tropical milkweed in natural areas. This replaces native plants and disrupts native ecosystems. But it’s not just the invasive quality of the plant that is damaging.
Butterfly weed, Asclepias tuberosa, is one of the most available and popular native species of milkweed. It sports attractive, bright blooms and is very hardy. For these reasons it is frequently stocked in nurseries around the state. Butterfly weed grows as a perennial in USDA Hardiness zones 3-10a. From late summer through early fall it produces orange or yellow flowers. A. tuberosa’s vibrant colors make it attractive to a number of pollinators.
Unless you visit a nursery that specializes in native plants, you are unlikely to find more than one native milkweed species for sale. Still, we think the rewards make these species worth the search. Adding these natives will make your landscape a refuge for Florida’s flora and fauna.
Other native milkweeds are available as well. A list is provided at the bottom of this article, taken from the Atlas of Florida Plants. You may have to seek them out in nurseries that specialize in natives or butterfly gardens. But for a pollinator-friendly garden, we think it’s worth the effort.
Two milkweed species are commonly offered for sale as “butterfly garden plants.” One, Asclepias tuberosa, is native to Florida. The other, Asclepias curassavica, is non-native. Which should you choose for your garden? Read on for more information about native and non-native milkweeds.
Another non-native milkweed is giant milkweed, also known as crown flower (Calotropis giganteana). It is native to Asia and tropical Africa. Giant milkweed makes an excellent specimen plant in Florida-Friendly landscapes between USDA Hardiness Zones 9-11. As its name suggests, mature plants are quite large, up to 15 feet tall and wide. For this reason we suggest adding it to the back layer in a pollinator garden.