Aegopodium podagraria goes by several common names. These include Goutweed, Goutwort, Ground Elder, Variegated Bishop's Weed, Cow Parsley, and Snow-in-the-mountain.
Although it has many uses in wildlife and woodland gardens, especially as groundcover on baren lands, it is considered an invasive species and/or a weed in many areas (and by most gardeners).
Aegopodium podagraria 'Variegatum' photograph by Funki Sock Munki.
Only grow it in an area where it is native (it is from Eurasia and has natural predators and competitors there) and not in an area where this vigorous plant is likely to grow out of control.
Even then it will still probably spread like crazy, so consider growing in a container to prevent root spread, and deadheading and cutting back to prevent it spreading by other means.
Wild Growing Aegopodium podagraria, photograph by Babij; CC.
It is a member of the Apiaceae family and thrives in USDA hardiness zones 4 to 9. The foliage is the main attraction of this perennial plant, which grows about 10 to 12 inches in height (25 to 30 cm) with a 2 to 4 foot (30 to 60 cm) spread.
Each leaf is made up of three smaller, serrated leaflets, which remain close to the ground making it an attractive ground cover especially in shady areas. Unfortunately Ground Elder is likely to outcompete and the leaves smother pretty much any other plant in the garden.
Its spring-blooming flowers are less impressive with single, dome-shaped blossoms made up of multiple miniature domes of tiny white flowers.
Close up of an Aegopodium podagraria flower, photograph by Andreas Rockstein; CC.
These grow on stalks that rise up above the foliage up to three feet (90 cm) in height.
The cultivar 'Variegata', is the most popular and attractive type that is actually grown by some harsh condition located gardeners. This displays green leaves with white along its edges.
However, because Aegopodium podagraria are super-spreader plants, unless the intention is to allow them to naturalize large open areas or woodland gardens, it is best to enjoy their beauty as container plants.
Goutweed / Ground Elder can grow in full sun, but because too much exposure can scorch its leaves, it is best to plant it in partial or even full shade.
These plants prefer moist, well-drained soils.
Quick to spread via their underground rhizomes, they are also self-seeding and some control over spreading can be had by deadheading the flowers before they turn to seed. This will also give them a more tidy appearance.
That said this perennial spreads crazily vis its roots, which are all but impossible to completely remove. Plants can be propagated by dividing them in early spring (there really is no need) or sowing the seeds indoors in a cold frame and later transplanting them.
A generally hardy plant, the foliage can be susceptible to leaf blight. However, new growth can be readily rejuvenated by mowing plants down on a high setting.
To be honest, the best way of getting rid of Aegopodium podagraria from the garden is by using a weedkiller; even this will probably need to be systematically and repeatedly applied as goutweed is resistant to most herbicides - even glyphosate. This will also mean you can grow only grow glyphosate tolerant plants in the area treated – most of which are also considered weeds - such as Morning glory (Ipomoea purpurea).
Another method is to dig down to about 30 inches (75 cm), and sieve the soil to remove all roots. This may require a mechanical digger and a lot of patience to sift all the soil through a half inch (1 cm) sieve.
Many people have resorted to extreme means to rid themselves of this weed, such as building a Patio or even moving to a new house and let it become someone else's problem.
Colourful Ground Elder leaves decaying in the autumn, image by carlfbagge; CC.