Plant laws in the United States can be surprisingly different from one state to another. Some plants are restricted because they spread aggressively, threaten native ecosystems, pose health risks, or contain substances regulated by law.
A plant that’s perfectly legal to buy in one state may be restricted just across the border. Before bringing an unfamiliar plant home, check your state and local rules so you know what is allowed where you live.
Here are 15 plants that are banned or restricted in parts of the United States.
Kudzu (Pueraria montana)
Kudzu arrived in the United States in the late 1800s and was once promoted as a way to help control soil erosion. It grows so quickly that it can cover trees, fences, utility poles, and buildings before people have much time to stop it.
Related: 10 plants that hate coffee grounds
Purple Loosestrife (Lythrum salicaria)
Purple loosestrife has tall stems covered with bright purple flowers, making it easy to mistake for a harmless garden plant. Once it spreads into wetlands, though, it can crowd out native plants that provide food and shelter for wildlife.
Yellow Iris (Iris pseudacorus)
Yellow iris is often planted near ponds because it handles wet soil and produces bright yellow flowers. It can spread through marshes, rivers, and drainage areas, where dense growth can push out native wetland plants.
Giant Hogweed (Heracleum mantegazzianum)
Giant hogweed was brought to the United States as an ornamental plant because of its unusual size and appearance. Its sap can cause serious skin reactions, including painful burns and blisters when exposed to sunlight.
Related: 10 Climbing Plants That Practically Grow Themselves
Water Hyacinth (Eichhornia crassipes)
Water hyacinth has attractive lavender flowers and floats on the surface of ponds, lakes, and rivers. It can multiply quickly and form thick mats that block sunlight and reduce oxygen available to aquatic life.
Giant Reed (Arundo donax)
Giant reed can grow more than 20 feet tall, making it tempting for gardeners seeking a tall screen. It can spread along waterways and crowd out native vegetation, leading some states to restrict its sale or cultivation.
Peyote (Lophophora williamsii)
Peyote is a small cactus native to parts of Texas, Mexico, and the Southwest that naturally contains mescaline. Federal law places mescaline and peyote under controlled substance rules, with limited exceptions for certain Native American religious practices.
Related: 15 Low-Maintenance Plants That Thrive in Hot, Sunny Weather
Opium Poppy (Papaver somniferum)
Opium poppies are attractive flowering plants, but they also contain compounds associated with opium and other controlled substances. Cultivation for producing illegal drugs is prohibited, and laws surrounding growing the plant for ornamental purposes can vary.
Cannabis (Cannabis spp.)
Cannabis laws differ widely across the United States, with some states allowing home cultivation under certain conditions. Other states restrict or prohibit it, while federal law continues to classify cannabis as a controlled substance.
Coca Plant (Erythroxylum coca)
The coca plant comes from South America and contains alkaloids associated with cocaine production. Growing, importing, or possessing coca plants is generally prohibited under U.S. federal law.
Related: 9 Plants That Help Make Your Backyard Less Appealing to Mosquitoes
Salvia divinorum
Salvia divinorum belongs to the mint family and is known for producing powerful hallucinogenic effects when consumed. Laws differ by state, with some places banning the plant while others restrict its sale or possession.
Khat (Catha edulis)
Khat is a shrub native to parts of East Africa and the Arabian Peninsula, where its leaves have traditionally been chewed for their stimulant effects. Its active compounds are subject to U.S. drug laws, making khat illegal under federal law.
Kratom (Mitragyna speciosa)
Kratom comes from a tropical tree native to Southeast Asia, and its leaves can produce stimulant or sedative effects depending on how they are used. It is not federally banned in the United States, but several states and local governments have placed their own restrictions on it.
Jimsonweed (Datura stramonium)
Jimsonweed can grow along roadsides, fields, and other disturbed areas, and its trumpet-shaped flowers can look harmless. Every part of the plant is poisonous and can cause severe symptoms if eaten, including confusion, hallucinations, and serious poisoning.
Wild Sugarcane (Saccharum spontaneum)
Wild sugarcane is a tall grass native to Asia that can spread quickly once established. Thick stands can crowd out native plants, which is why some states have placed restrictions on its sale or cultivation.
