Did you know that 60% of all invasive plants in the US have horticultural origins1? With thousands of invasive species in the nation, a large proportion of those come from escaped ornamental plants – those that are planted in backyards and make their way into natural areas. While ornamental plants can certainly be showy, hardy, and good at spreading in gardens, some of these traits are what can make a plant invasive, too. It’s not always easy to tell an invasive plant from a non-invasive ornamental just by looking at them. It’s even possible for a plant to become invasive over time after environmental conditions change, including climate change. This means that what you plant matters!
In New York, some invasive species are regulated or prohibited from sale under regulation Part 575 (est. 2014). This legally binding list prevents the sale, possession, transport, import, purchase, and introduction of some of the most invasive plants in the state – like garlic mustard, kudzu, knotweed, and phragmites. While this effective regulation includes 74 aquatic and terrestrial invasive plants, not every invasive plant is prohibited. This means that you may encounter some invasive plants at the nursery without realizing!
This means it’s up to you – home gardeners, landscapers, and horticulturists – to begin looking at gardens in a new way by seeking out native plants, avoiding invasives, and creating a more biodiverse and resilient habitat right at home. While we are working on developing educational materials that highlight the local Long Island invasive species to avoid planting, check out this resource of non-prohibited invasive plant species provided by the NE RISCC Management Network to guide plant selection for your garden2.
Fortunately, there are many ways to help prevent and mitigate invasive species with horticultural origins. Here are some ways that you can do your part!
Choose native plants for your gardens.
While not all ornamental plants are invasive, the easiest way to avoid the guesswork of which non-native plants are invasive is to choose native species for your gardens. Native plants also have a host of other advantages anyway from their benefits for pollinators and wildlife to their low maintenance features (many are perennial, drought tolerant, etc).
There are already some businesses solely dedicated to the propagation and sale of native plants. Check out the Long Island Native Plant Initiative, Dropseed Native Landscapes, Long Island Natives, and more, for the next addition to your garden.
Ask your local nursery to carry more native plants.
One of the prime reasons ornamental and invasive plants end up in our gardens and landscapes is because that is simply what is available at the nursery. Imported ornamental plants have been historically planted much to the harm of local ecosystems. It’s time to give the landscape what it needs and bring native species back home again.
Become familiar with invasive plants.
Check out these resources to become familiar with invasive plants in the region:
3. New York Natural Heritage Program Invasives Tier List
Remove invasive plants from your garden, especially those listed as Tiers 1-3.
While you don’t have to remove every non-native plant from your backyard, be sure to check that your ornamentals are not listed as invasive in NY. If you do find that some of your non-native plants are invasive, check LIISMA.org or search the web for tips on the removal of that plant.
Report populations of escaped ornamental plants that are listed in Tiers 1-3.
Try the apps iNaturalist or iMapInvasives to report invasive plants you encounter. We want to know if these plants are in your backyard or have escaped into the natural landscape! On iNaturalist, search “LIISMA” under projects and join the LIISMA LIFERs, EDRR Species in LIISMA, and a variety of other LIISMA groups for your invasive species observations to be automatically added to these projects. We review these observations and rely on them as part of our early detection efforts!
Report prohibited invasive species sold at nurseries.
Here is the full list of prohibited plants in NY. Report any nurseries selling prohibited plants to the Department of Agriculture and Markets.
Tell family and friends how they can help.
Share this article with a friend or tell someone about what you learned!
References:
1. https://www.risccnetwork.org/beaury-et-al-2021
2. Beaury EM, Patrick M, and Bradley BA. 2021. Invaders for sale: the ongoing spread of invasive species by the plant trade industry. Frontiers in Ecology and Environment, doi:10.1002/fee.2392. PDF
