invasives

My Pachysandra is Dying, What Can I Plant in Its Place?

May 6, 2019November 17, 2021Maryland Grows9 Comments

Resident seeks groundcover options to replace Pachysandra. Photo: University of Maryland Extension / Ask an Expert

Q: My Pachysandra is Dying, What Can I Plant in Its Place?

A patch of Japanese Pachysandra in my yard was formerly healthy but in the past three years, it has died back. I would like to plant deer-resistant plants or groundcover in its place. Can you recommend some perennials I can try? This area gets filtered sun most of the day.

Answer: Volutella is a common fungal disease of Japanese Pachysandra that attacks both the leaves and stems and causes dieback symptoms. It is most severe in overgrown plantings and is often associated with scale (insect) infestations. This may have contributed to the decline of your plants.

It is a good idea to consider different options for this space. In addition to its susceptibility to Volutella dieback, Japanese Pachysandra has escaped garden cultivation and is now invasive in some natural areas of Maryland. We no longer recommend planting it. In the forest understory, it outcompetes native plants such as our spring ephemeral wildflowers and the wildlife (insects, birds) they support.

japanese pachysandra in a forested area — *Invasive Pachysandra terminalis covers a large area of forested ground in Howard, County, Maryland. Photo: C. Carignan*

There are other groundcover choices that are unique, beautiful, non-invasive, and adapted to Maryland’s growing conditions. For a partially shaded, moist area, try a combination of ferns – Christmas fern (Polystichum acrostichoides) and marginal woodfern (Dryopteris marginalis), sedges – blue wood sedges (Carex glaucodea or Carex laxiculmus) and Pennsylvania sedge (Carex pensylvanica), Canadian ginger (Asarum canadense), golden groundsel (Packera aurea), foam flower (Tiarella cordifolia), and creeping phlox (Phlox stolonifera). Some of these plants also support pollinators.

*Groundcover plants were in bloom in April in the native plants garden at Camden Yards, Baltimore. From front to back: Phlox, Foamflower, Golden Groundsel. Photo: C. Carignan*

Additional Resources

Planting Groundcovers | Home & Garden Information Center

Twelve Easy Native Plants for Shade | Montgomery County Department of Environmental Protection

Groundcovers | Plant NOVA Natives

By Christa K. Carignan, Maryland Certified Professional Horticulturist, Coordinator, University of Maryland Extension Home & Garden Information Center

Have a plant or insect question? University of Maryland Extension’s experts have answers! Send your questions and photos to Ask an Expert.

How Invasive is Chinese Silvergrass?

January 12, 2018March 18, 2022Maryland Grows5 Comments

Chinese silvergrass, Miscanthus sinensis, is a beautiful ornamental grass. In its native range, it inhabits disturbed areas and meadows. Here in North America, it escapes cultivation to occupy similar types of places, and, given enough time it can displace native meadow vegetation. If you have not yet had the opportunity to see how invasive this species can be, then this is your chance.

I was driving home from a meeting in Baltimore County when I started to notice occasional Miscanthus plants growing in unkempt areas along the roadside. This went on for a mile or two, and then suddenly I arrived at what quite clearly was the epicenter. The lighting was perfect, so I pulled over, grabbed my little video camera and went for a walk around the area to see how extensive the infestation might be. The footage posted here is unedited so you will see exactly what I saw on that walk.

I mentioned the Miscanthus to a friend who used to walk past this substation to get to school, and he told me Miscanthus was planted at the substation in the mid-1980s, and that it has spread a little each year ever since. Now it occupies several private properties, and as per his description “miles” of the local power lines.

According to the U.S. Forest Service, Miscanthus spreads by both seeds and rhizomes. It is very difficult to eradicate once established because even small bits of rhizome will start new plants. They also warn that it is highly flammable, and at this time of year it should be considered a fire hazard.

What about you? Do you see Miscanthus escaping in your area? Leave us a comment!

Learn more about invasive plants in Maryland.

By Sara Tangren, Ph. D
Agent Associate | Master Gardener Trainer | Sustainable Horticulture and Native Plants

Spotted Lanternfly: A New Invasive Pest That is Too Close for Comfort

December 11, 2017November 17, 2021Maryland Grows4 Comments

spotted lanternfly adult — Spotted Lanterfly Adult. Photo: Pennsylvania Department of Agriculture, Bugwood.org

Spotted Lanternfly (Lycorma delicatula) is an insect native to China that was first detected in Southeastern Pennsylvania in September 2014. It has spread fairly rapidly since then. There were recent finds in Delaware and New York. Both were dead individual adults.