Bishop Weed: Most Hated Plants
I’d like to dedicate this post to my blogging friend, Carol at Flower Hill Farm, for her long-suffering with this invasive plant, her nemesis, Bishop Weed, also known as Goutweed (Aegopodium podagraria).
But first, a disclaimer. I call this ongoing series “Most Hated Plants,” but some have taken issue with “hating” poor defenseless plants. Most Hated Plants is really a shorhand way of saying:
- I don’t really hate the plants.
- I do hate that nurseries continue to propagate and sell these plants
- I hate that landscapers continue to install them
- And I hate that people continue to plant them
- Invasive plants are wiping out native habitats leaving wildlife no place to go
- Invasive plants cost taxpayers $138 BILLION dollars every year
- I really would like to see homeowners do their homework prior to purchasing ANY plant
But instead of saying all of that every time I refer to the damage caused by invasive plants, I simply say MOST HATED PLANTS as my short hand.
Bishop Weed is native to Europe, northern Asia, and Siberia and was brought to this country as an ornamental plant. It was first noticed to have escaped cultivation and become invasive in Rhode Island in 1863.
Also known as Goutweed, it wreaks havoc in moist, partly shaded woodlands and disturbed areas. It forms a dense mat that prohibits other plants from establishing.
This trait is especially harmful in natural wooded areas where it outcompetes native plants. Because of this, many native woodland plants are now highly endangered.
I’ve been attempting to rid my property of this plant since 2001 when I first moved in. It feels like a losing battle because it returns with a vengeance especially after the rain. We pull, and we pull, and then we pull some more. But it always comes back.
That’s because Bishop Weed not only spreads by seed, it also spreads by underground runners. If you’re pulling but don’t get every last piece of those runners out of the ground, it will pop up again almost immediately.
My neighbor across the street is the head propagator for Morris Arboretum. Her garden is her own beautiful private botanic garden. Really, it’s stunning! But she has been battling Goutweed for the 30 years she’s lived in her house. Trust me, she REALLY hates this plant!
Risa Edlestein, my blogging buddy at Garden and the Good Life, has started a discussion on the best ways to eliminate this invasive plant from the landscape at the Ecological Landscaping Association Group on LinkedIn.
It is banned for sale in Connecticut, Massachusetts, and Vermont, and is considered a noxious pest from Eastern Canad to Georgia and into the midwest, plus is invasive in the Pacific Northwest.
A much better alternative to this noxious, invasive plant is the native Golden Alexanders (Zizea aurea), in the same family as Bishop Weed, but a much gentler inhabitant of native ecosystems, and a host plant for Black Swallowtail butterfly caterpillars.
So, Carol, this one’s for you, in hopes that you will make headway in this battle!
Although it has extremely vigorous growth and invasive tendencies, bishop’s weed is useful in the right setting. If you are looking for an easy-to-grow groundcover to quickly fill a confined space, consider this plant. Its attractive light green foliage edged in cream looks nice all season long in part shade to full shade. Airy panicles of white blooms emerge above the foliage in summer.
Worth the Risk?
Bishop’s weed, as you might guess by the name, is a plant gardeners love to hate (after all they named it a weed). When introduced in the eastern United States as an ornamental plant, people loved its ease of growth and vigor. It helped that the plant had attractive foliage. Because it is extremely easy to share as a simple division or clipping from the garden, it became a common pass-along plant and quickly made its way into ornamental gardens. Eventually, people realized the mistake: Once planted, it can be nearly impossible to eradicate. The vigorous growth habit, coupled with its quick regeneration and copious seed production, make this plant a beast to control. For these reasons, it is important to think long and hard before planting bishop’s weed. Even then, it should only be planted in confined areas like between a sidewalk and a house where it has solid physical boundaries.
Bishop’s Weed Care Must-Knows
As the name implies, bishop’s weed is an extremely easy plant to grow, even in harsh conditions. Ideally, it likes consistently moist, well-drained soil, although it can take some drought. During long dry spells, the foliage, especially of variegated species, tends to crisp and burn.
For the best-looking foliage, plant it in part sun. This ensures that the plants get enough light to have nice variegation but also protects them from burning on the sensitive leaves. Its vigorous nature means it grows fine in full shade or even full sun.
If your plants begin to look a little ragged, mow them back to encourage a new flush of growth. It’s also a good idea to remove any seed heads after blooming to control spreading. Other than leaf blight in the heat and drought of the summer, these plants are fairly untouched by pests and disease.
Generally speaking, gardeners end up more concerned about removing the plant. Much easier said than done: You must dig up the underground rhizomes without leaving even the smallest piece behind.
Manual removal of the plants is tedious and may need to be repeated until all of the plants are removed. They also are tough enough to survive several applications of harsh herbicides.
The best method of eradicaization is solarization: Cut back the plants and cover the bed with black plastic for a whole growing season to block out any sunlight and heat the soil to high temperatures.