The best place to buy milkweed for monarch butterflies is a native plant nursery in your region, and the easiest way to find one is through the Xerces Society’s Milkweed Finder at xerces.org. This free, searchable database connects you with nurseries and seed vendors across the United States, Canada, and Mexico that carry species native to your area. Buying local matters because monarchs depend on the specific milkweed species they evolved alongside, and locally sourced plants are adapted to your soil and climate.
How to Find a Vendor Near You
The Xerces Society maintains two directories worth bookmarking. Their Milkweed Seed Finder lets you search by state for businesses that sell milkweed seed, while their broader Native Plant, Seed and Services Directory covers nurseries selling live plants (often called “plugs” or transplants). Both are free to use.
A few things to keep in mind when using these tools. Milkweed seed is currently unavailable in some parts of the country, so if your state returns no results, it simply means no vendors have been listed there yet. Also, a vendor’s physical address doesn’t always reflect where their seed was collected. Always ask about seed origin and try to plant seed sourced as close to your area as possible. Some listed vendors are wholesale only and require minimum orders, so check before placing an order.
Beyond online directories, many local garden centers, native plant sales run by conservation districts, and botanical garden shops carry milkweed seasonally. Spring plant sales hosted by native plant societies are particularly good hunting grounds.
Free Milkweed for Schools and Nonprofits
If you’re planting for a school, park, or nonprofit, Monarch Watch runs an annual program that ships free flats of 32 milkweed plugs, including shipping, in species native to your region. Applications typically open in early October and close in early to mid-February, with plants shipping between April and mid-May. The program is competitive. As of early 2026, Monarch Watch had received over 200 applications and plans to award free milkweed to 200 schools. Applications are processed in the order received, so submitting early improves your chances. The program covers most of the eastern and western monarch breeding range but does not currently include the Rocky Mountains.
Which Species to Plant by Region
Choosing the right species is just as important as finding a good vendor. Monarchs lay eggs on milkweed and their caterpillars eat nothing else, but not all milkweed is equal. Native species support the full lifecycle without the risks that come with non-native alternatives. Here’s what to look for based on where you live.
Northeast
Common milkweed is the workhorse of this region, thriving in fields, roadsides, and garden edges. Butterfly weed adds bright orange flowers and tolerates drier soil. Swamp milkweed does well in wetter areas and rain gardens. Poke milkweed is a good choice if you have shaded or wooded spots.
Southeast
Butterfly weed and white milkweed both perform well across the Southeast. Aquatic milkweed suits low-lying, moist areas. In parts of Florida, sandhill milkweed is a regionally appropriate option adapted to sandy soils.
South Central (Texas and Surrounding States)
Green antelopehorn milkweed and antelopehorn milkweed are the go-to species here, both well suited to the heat and drier conditions of the region. Zizotes milkweed is another native option for this area.
West
Showy milkweed is widely adapted across western prairies and savannahs. Mexican whorled milkweed works well in dry climates and plains across much of the West, though it’s not native to Colorado, Utah, New Mexico, or Arizona.
Avoid Tropical Milkweed
Tropical milkweed is the most widely available milkweed at big-box garden centers, recognizable by its red and yellow flowers. It’s also the one species you should not plant. The problems are serious and well documented.
Unlike native milkweeds that die back in winter, tropical milkweed stays green year-round in mild climates. This tricks monarchs into breeding through fall and winter instead of migrating to their overwintering sites in Mexico. Research published in the Proceedings of the Royal Society found that exposure to tropical milkweed advances reproductive development in monarchs that should be in a non-breeding state, essentially breaking them out of the dormancy they need for successful migration. Monarchs that resume breeding mid-migration become less efficient fliers and burn through energy reserves, making it unlikely they’ll complete the journey.
The year-round growth also creates a parasite trap. A protozoan parasite called OE accumulates on leaves that never die back and get replaced. At some tropical milkweed sites, infection rates reach 100% among resident monarchs. When migratory monarchs pass through these areas in spring, they encounter heavily infected local populations, spreading the parasite into the broader migratory generation.
Several California counties, including Marin, Contra Costa, San Mateo, and Ventura, have banned nursery sales of tropical milkweed after the state Department of Food and Agriculture declared it a noxious weed in 2022. Even where it’s still legal, conservation groups strongly discourage planting it anywhere along the monarch’s migratory flyways.
Starting Milkweed From Seed
Buying live plugs is the fastest route to an established milkweed patch, but seeds cost a fraction of the price and let you cover more ground. The catch is that most milkweed seeds need a period of cold, moist conditions before they’ll germinate, a process called cold stratification that mimics winter.
How long this takes varies by species. Common milkweed is the easiest: as little as two weeks of cold stratification at refrigerator temperatures (around 40°F) can push germination rates above 90%. Swamp milkweed typically needs one to four weeks. Butterfly weed is the most variable and often the slowest, requiring anywhere from three weeks to as long as three or four months of cold treatment depending on the seed lot.
The simplest approach is to sow seeds outdoors in late fall and let winter do the work naturally. If you’re starting seeds indoors in spring, place them in a damp paper towel inside a sealed plastic bag in your refrigerator for the appropriate number of weeks before planting. Seeds started indoors in late winter can produce transplant-ready seedlings by the time warm weather arrives.
What to Look for When Buying Plants
Milkweed naturally attracts a crowd of insects. When you’re inspecting plants at a nursery, check the undersides of leaves for clusters of bright yellow aphids (oleander aphids), which are the most common hitchhiker. A few aphids aren’t a dealbreaker since they’re easy to rinse off with a strong spray of water, but heavily infested plants with curling or yellowing leaves are best avoided. Look for plants with firm, upright stems and full, green leaves. Healthy milkweed leaves are broad and oval-shaped, and on common milkweed they’ll feel slightly fuzzy on the underside.
If you’re buying plugs online, expect them to arrive small, often just a few inches tall. This is normal. Milkweed puts significant energy into root development first, and a small plug with a strong root system will establish faster than a large, rootbound plant. Most species will reach full height within their first or second growing season.