Some plants just don't know how to behave.
Sure, they might be beautiful and make a good first impression, but after they get settled in at home, it becomes apparent they just don't play well with others. Aside from bad manners, one thing these plants have in common is that they were brought here -- deliberately or inadvertently -- from elsewhere.
Kudzu, which is among the worst weeds known on these shores, is native to Asia. But it didn't arrive in the carry-on baggage of a tourist. It was actually imported to the United States in 1876 for the Centennial Exposition in Philadelphia. On purpose. And if that wasn't bad enough, more was imported for the New Orleans Exposition in 1884, where it was displayed at the Japanese pavilion. The perennial weed, which can grow 12 inches in a 24-hour period and as much as 50 feet in a single season, has since earned the nickname "the plant that ate the South."
Here in New York we have Persicaria perfoliata, which has been nicknamed "mile-a-minute-weed" and which some people fear could become the plant that ate the mid-Atlantic and Northeast. Just like kudzu, it grows and spreads prolifically. Unlike kudzu, this plant arrived accidentally, reportedly aboard a Japanese cargo ship about 100 years ago. The annual weed, which has triangular leaves and sports pretty blue berries, is especially becoming a nuisance on the North Fork, where it is spreading rapidly. Its seeds can survive in the soil for as long as six years, so it's important to pull plants, bag them tightly and dispose of them in the trash on sight, before berries drop.
What's worse, weeds aren't the only plants that can be invasive. Seemingly innocent ornamental perennials and annuals -- many of which are readily available at local nurseries -- can lead to gardeners' remorse in just a few short seasons. Unless you do your research, you can find yourself double-crossed by their seductive wiles.
Bad guys and options
To help keep you grounded, here are some of the biggest offenders, along with some native and demure alternates to consider:
Invasive: Purple loosestrife (Lythrum salicaria, Lythrum virgatum)
Native alternative: Gayfeather (Liatris pycnostachya)
Invasive: Dame's rocket (Hesperis matronalis)
Native alternative: Carolina phlox (Phlox Carolina)
Invasive: Ox-eye daisy (Leucanthemum vulgare)
Native alternative: Blackfoot daisy (Melampodium leucanthum)
Invasive: Queen Anne's lace (Daucus carota)
Native alternative: Hairy angelica (Angelica venenosa)
Invasive: Rose of Sharon (Hibiscus syriacus)
Native alternative: Oakleaf hydrangea (Hydrangea quercifolia)