Invasive Plant of the Month: Creeping Jenny (Lysimachia nummularia)

You may ask, why are garden centres still selling invasive plants since they are so harmful? Good question.

That’s why the Canadian Coalition for Invasive Plant Regulation (CCIPR) wants the Federal government to regulate the sale of invasive plants or provide labelling and education to inform the public of the danger.

Some provinces do regulate some invasive species, but the rules vary from province to province.

For example, yellow flag iris is regulated only in Alberta, British Columbia and Manitoba. The Multiflora Rose is an invasive ornamental plant that appears on lists of invasive plant councils across Canada but is unregulated in all Canadian provinces.

Individuals can get involved by becoming a CCIPR supporter – free of charge and without obligations:  https://ccipr.ca/get-involved/

Businesses can show their support by becoming a partner and have their logo displayed on the website – again free of charge and without obligations: https://ccipr.ca/partners/

Focus on Creeping Jenny (Lysimachia nummularia):

Creeping Jenny, also called Moneywort, is native to Europe and is a long, crawling plant that can spread very tenaciously.

The toothless, spade-shaped leaves can vary from green to yellow in colour, based on sunlight exposure. Flowers are yellow with dark red spots. It is often mistaken for Creeping Charlie.

Only reaching two inches in height, this plant can grow to two feet long and has an unusually extensive root system. It is often touted as a good ground cover for wet areas, and its trailing foliage is used for decoration in hanging baskets and other planters by garden centers.

Once it is established, it can be hard to get rid of and will crowd out plants that get in its path.

Unfortunately, the same properties that make it a desirable ground cover for gardeners and landscapers turn it into an effective invader in natural wetland ecosystems.

It is known to escape from cultivation into forested floodplains and other wetlands, where it often forms dense mats. It is also a prolific producer of seeds.

Please do not buy this plant or trade it with your friends.

• Spread: Creeping Jenny can spread quickly and form dense mats that exclude other plants. It can grow in a variety of light conditions and wet areas.

• Hard to remove: Once established, Creeping Jenny can be difficult to remove completely.

• Outcompetes native plants: Creeping Jenny can outcompete native plants for resources. 

Creeping Jenny control is not always easy, and it’s not always quick. If the plant is established in your yard, it may take two growing seasons to eradicate it.

HOW TO MANAGE CREEPING JENNY:

Managing Creeping Jenny is challenging but achievable with persistence and a multi-step approach:

• Manual Removal: Before flowering, small areas can be pulled out by hand or dug out by using a shovel. Check every couple of weeks for new plants emerging, as their roots are very extensive and deep. Do not put plants in the compost or municipal green waste; put in garbage instead.

• Smothering: Larger areas can be covered with a tarp or cardboard to block sunlight.

• Herbicide Treatment: Alternately, small or large areas can be eradicated by using an herbicide. Use herbicides only as a last resort, following local regulations to minimize environmental harm.

After removal, replant the area with regionally appropriate native plants. This step is essential to prevent reinfestation and to restore ecosystem health.

Native plants will also attract pollinators and wildlife, improving biodiversity in your garden.

A good choice would be Canada Anemone – Anemone canadensis (https://onplants.ca/shop/anemone-canadensis/)

LEARN MORE AND TAKE ACTION:

Education is key to combating invasive plants. Learn to identify invasive species and choose native or non-invasive alternatives for your garden.

Focus on managing one or two invasive plants at a time and be patient—successful eradication takes time and persistence.

For more information, visit:

Ontario Invasive Plant Council www.ontarioinvasiveplants.ca

Canadian Coalition for Invasive Plant Regulation www.ccipr.ca

Grow me Instead guide www.ontarioinvasiveplants.ca/resources/grow-me-instead

Renee Sandelowsky is a volunteer with the Canadian Coalition for Invasive Plant Regulation