How Do You Get Rid of Goutweed?

Wondering where that pretty patch of variegated, flowering ground cover on the side of your house came from? Beginning to worry that it might take over your whole yard if you don’t do something to stop it? Goutweed is a problem plant for many gardeners in North America, but it can be eliminated if you’re committed to doing so. In this article, master gardener Liz Jaros tells you how to identify goutweed, discusses the problems it creates, and suggests some tried and true methods for getting rid of it.

Written by Liz Jaros Horticulture review by Sarah Jay Last updated: April 18, 2024 | 4 min read

Top view, close-up of a flowering Goutweed plant. Goutweed, also known as Aegopodium podagraria, is a vigorous ground cover plant with distinctive foliage and tiny white flowers. Its leaves are deeply lobed, resembling small umbrellas, and emerge in dense clusters from creeping stems. The foliage is variegated, featuring shades of green and white. Goutweed produces delicate clusters of small white flowers held above the foliage on slender stalks.

Contents

If you live in the Midwest or Northeast U.S., you’ve probably had a run-in with Aegopodium podagraria. You may know it by the nickname ‘goutweed,’ which it earned as a medicinal plant assigned to arthritic and podiatric diseases in the past. You may also know it by one of its other aliases – bishop weed, snow-on-the-mountain, or ground elder.

Seemingly benign and relatively attractive, goutweed pops up in temperate landscapes all over the northeast hemisphere. It suppresses weeds like a champ with its dense matt of variegated blue-green foliage. In early summer, it sends up cheerful white clusters of umbel-shaped flowers.

Chances are, upon first encountering this charming little ground cover in your garden, you may have encouraged it to do its thing. And chances are, if you’re reading this article right now, you’ve probably discovered that this was a huge mistake.

Though it prefers dappled sunlight to full sunlight, goutweed grows easily in most soil and sun conditions. It spreads quickly by rhizomes with lengths of up to eight feet wide and depths of a foot or more below the soil surface. It also tolerates both drought and flood. Unfortunately, this laid-back, low-maintenance growing profile is exactly what makes goutweed such a major nuisance plant for many gardeners.

If you find yourself with a goutweed problem, do not fret! Epic Gardening is here to help. Read on for a detailed look at this aggressive garden foe. We’ll learn how to identify it and discover some methods for getting rid of it.

How to identify it

Close-up of a cluster of flowering ground elder in a shady garden. — This resilient parsley cousin thrives in partial shade.

Goutweed is a member of the parsley family (Apiaceae). Its leaf characteristics are similar to those found on carrots, parsley, and mint. Stems are fleshy and grow directly from the rhizomes, terminating with a cluster of three-part leaves that may be subdivided. Leaves are mostly ovate with toothed edges and sometimes smell like carrots when crushed between your fingers.

Leaves are typically blue-green to sage green in color. Variegated versions have creamy white margins in a pattern that’s similar to a hosta. They form a dense canopy over the soil surface, maxing out between six and eight inches in height.

Goutweed plants prefer partial shade, but the sun will not kill them. Leaves may wilt or appear scorched at their margins, but they will keep photosynthesizing, even in direct light. Conversely, full shade does not shut them down either. They may spread a little slower, but they’re still going to spread!

Flower stalks erupt from rhizomes in late spring to early summer, reaching heights of one to three feet. This is significantly taller than the leaf canopy and may look like a separate plant or weed, but they are very much derived from the same root system. Blooms are compound and umbel-shaped (like an umbrella) with a flat or slightly curved top. Individual flowers are small and white with five petals.

Why it’s a problem

Park views on summer day with invasive flowering plant Goutweed. Goutweed, scientifically known as Aegopodium podagraria, presents as a low-growing perennial herb with deeply lobed, dark green leaves. It features clusters of small, white flowers in umbrella-like arrangements. — Banned in select states, Goutweed suffocates native plants.

Goutweed is included on the invasive species lists for several U.S. states and is considered a major threat to landscapes in Michigan, Wisconsin, Connecticut, New Jersey, Pennsylvania, and Vermont. Conditions there are so friendly to goutweed, and the potential for mass expansion is so high that buying, selling, or growing goutweed in these states is strictly prohibited.

Most of goutweed’s threat stems from its ability to form a dense mat on the forest floor and crowd out other plant species. Its aggressive growth habit displaces native plants and reduces biodiversity. This plant has a detrimental effect on the microbial content of soil. It also discourages conifer replenishment and the regeneration of native understory trees.

Counter to popular belief, goutweed does not spread easily through seed dispersal as some of its parsley family relatives do, like Queen Anne’s lace, hogweed, and fennel. Its primary mode of expansion is through a dense network of rhizomes that stretches both wide and deep to consume the soil in which it’s growing.

How to get rid of it

Once you’ve confirmed that you’re dealing with goutweed, it’s time to make a plan to get rid of it. While it’s not impossible to fully and finally eradicate this garden menace, you should think of the process as a long-game attack and not an overnight fix. It will take time, patience, and persistence to remove goutweed from your landscape. Let’s look at your options for getting it done.

Dig it up

Digging up weeds in a sunny garden. Close-up of a large garden shovel stuck into the soil. Various weeds grow in the garden bed, including goutweed. A garden shovel consists of a long handle made of metal, attached to a metal blade with a flat edge. — Combatting goutweed requires deep digging and thorough removal for success.

The most strenuous and, arguably, most effective way to remove goutweed from your property is by digging it up the old-fashioned way. This approach requires a lot of sweat equity and a LOT of deep digging, so it’s only recommended for small invasions. But it’s very effective when done properly. Here are the steps:

Use a long-handled, round-point shovel.
Determine a cutting boundary that exceeds the width of the goutweed patch by at least one foot on all sides.
Dig to a depth of 18 inches or at least six inches below the rhizome mat, working from perimeter to center.
Excavate all of the soil and roots until you’re sure the remaining soil has no trace of goutweed rhizomes.
Place dirt and roots in contractor bags and dispose of them safely.
Monitor the area carefully for the next several seasons, digging up goutweed as soon as it emerges.

Smother it

Close-up of black tarp on the ground weighted down with rocks. A black tarp is a large, flexible sheet made of heavy-duty polyethylene material, dyed black to absorb sunlight. — Suppressing goutweed involves smothering it with a tarp.

For larger goutweed patches or when hand digging is not an option, smothering is another way to go. Put simply, this approach employs occultation: a tarp or light-blocking barrier to prevent leaves from photosynthesizing and nourishing the colony’s root system. Although it may be ugly and take considerable time to work, a smothering approach will usually kill some of the plant mass if you’re patient. Note that this method is not as effective as mechanical removal. Here’s how it’s done:

Choose a day in early spring before roots have begun aggressively feeding.
Transplant any materials in the target area that can be safely moved, taking care to remove all traces of goutweed!
Use a dark-colored tarp or sheet of plastic to cover the entire section of goutweed, plus one foot all around.
Use landscape stakes or wire pins to secure the tarp in place.
Anchor corners with heavy pots or statuary.
Do not disturb until the following spring.
Remove the tarp and dig up any remaining rhizomes.
Plant a new groundcover or perennial to discourage goutweed reinvigoration.

Mow it down

Close-up of a gardener in ears of corn and green light pants mowing weeds with a lawn mower. The handy lawn mower is a compact device, featuring a sleek design with a durable metal or plastic frame. It has a single cutting blade housed underneath, enclosed by a protective housing. — Mow diligently to starve goutweed and reclaim your space.

If your goutweed is growing in a large area or an untended lot, you may be able to shut it down by scalping it with the lawn mower. Like the tarp method, removing your goutweed leaves prohibits photosynthesis and ultimately deprives roots of nutrition. This does not actually remove the plant, but it does slow its spread.

Adjust your blade to the lowest possible setting and mow the site twice weekly to prevent leaves from growing back. With diligence and patience, this method can be effective, but it may take a few years.

Burn it

Close-up of a gardener burning down weeds in a flower bed in the garden using a torch. The flowerbed is separated from the lawn by a border and has the characteristic black color of burnt grass. — Torch goutweed away with a landscape dragon for short-lived results.

Another way to prevent photosynthesis is through controlled burning with a propane wand. Referred to in the horticultural industry as a ‘landscape dragon’ or ‘weed torch,’ this flaming tool delivers the same smothering effect as the black tarp approach, but it’s considerably less unsightly.

For the landscape dragon to be effective, visit the goutweed patch roughly twice a week and burn stems completely to soil level before leaves have a chance to regrow. This may take a season or two of diligent follow-through, and it isn’t as effective as pulling and digging. Combine this with other methods for the best results. Still, some landscapers swear by it.

Final Thoughts

A goutweed invasion is usually the result of landscape neglect or poor decision-making. Let it go for a while because it’s pretty, and it keeps other weeds down, and you’ll surely have regrets one day. The good news is that goutweed can be controlled if you commit to getting rid of it and are willing to put in the work. By combining mechanical methods with other means of control, you can handle this issue.