Contributed by Curtis Hawley
Inspired gardeners often ask our crew with hopeful expressions on their faces: “I was driving down the street the other day and saw this amazing plant, could you get me one of those?” As knowledgeable horticulturists, it is our responsibility to be aware of all aspects of a plant before we order you the latest garden showstopper. We first go through an in-depth list to learn about the plant including sun/shade requirement, moisture tolerance, acidity/alkalinity preference and competition with neighboring plants. Sometimes we learn through this process that a requested plant is considered an invasive species.
When it comes to plants, the definition of invasive can get a little muddied. For all practical purposes, an invasive species is a non-native plant that is introduced to a new environment where it behaves in a rather aggressive manner due to very little competition and/or extremely ideal growing conditions. Although Poison Ivy or Golden Rod can be rather aggressive at times, they are not considered invasive species since they’re native plants. A couple of examples of common invasive species are Oriental Bittersweet and Japanese Knotweed. These are both very aggressive plants often found growing on roadsides and taking over areas quickly. We don’t get many requests for Knotweed, so let’s talk about some popular plants that do qualify as invasives and some excellent, eye catching native alternatives.
Round 1: Burning Bush (Euonymus alatus) vs. Viburnum nudum ‘Winterthur’
This shrub is commonly requested in the fall. Admittedly, its 4-week long bright fiery red display is quite stunning. Outside of its fall showcase, however, I personally don’t find this shrub to be very aesthetically pleasing, and of course because it’s invasive I don’t recommend it! When someone asks for this Viburnum, I like to present my favorite alternative that I think outdoes it while being more friendly to neighboring native plants.
This is a native plant, so that’s a good place to start. Not only is a native plant by definition not invasive, but it’s usually not overly aggressive either. But you know what’s even better about native plants? They’re being grown in their natural environment, meaning there’s a very high likelihood that the plant will thrive!
Here are some other great advantages of this non-invasive alternative:
- Much nicer flower show in May/June (Burning Bush has a non-distinct flower)
- Flowers are followed by a colorful fruit structure that changes color from red to blue throughout summer
- Fall colors feature maroon to dark red-purple
- Great food source for pollinators
- Better ornamental shaping from pruning (Burning bush tends to get sheared into “meatballs”)
Stay tuned for Parts 2 and 3 of the Invasive vs. Non-Invasive Plant Showdown, including another very popular shrub and one of the most popular plants you can still buy today…