Green and Growing: Some native plants get aggressive, and that’s why we love them

July 18, 2019 12:01 am • Last Updated: July 18, 2019 12:05 am

By Kathy Connolly, Special to The Times

Ostrich fern (Matteuccia struthiopteris) will take over both sunny and shady areas with tall, graceful fronds. Use it in areas where you don’t want to mow or garden ever again, as it is very tenacious.

We’ve had a bit of rain lately, and most plants are acting like giddy teenagers after a six-pack of energy drinks.

“It’s taking over the universe,” said one friend of a plant that was claiming new territory around his backyard. “Can you take a look and tell me if I should get rid of them?”

I arrived with two of my favorite invasive weed identification books but needn’t have. The dreaded invader was hemp dogbane (Apocynum cannabinum), a plant more likely to be found on the pages of “Native Plants of the Northeast” by Donald Leopold.

Who’d have thought a native plant would fail to mind its manners? In fact, when some natives get aggressive, they outcompete non-native invasive weeds. In the horticultural world, this quality is sometimes called “competitive exclusion.”

My friend’s reaction to dogbane-in-the-fast-lane also reminded me that it’s easy to love the idea of native plants and easy to praise their value for pollinators, birds and wildlife. But when they misbehave, something’s gotta give — and it’s usually not us.

Might we consider an alternative point of view? One of these powerful spreaders may reduce the spaces available to the worst weeds. They also offer a way to replace lawn areas that are no longer desired.

Dogbane (too bad about the name) is not alone. High on the list of natives-we-love-to-hate are root-spreading members of the mint family, such as mountain mint (Pycnanthemum muticum) and wild bergamot (Monarda fistulosa). Among fall flowers, some people object to the vigor of white snakeroot (Ageratina altissima, formerly Eupatorium rugosa), a perennial with profuse white flowers and deer-resistance that is hard to match.

Some people believe the native goldenrods make them sneeze, but it is ragweed, another vigorous native, that affects those of us with allergies.

Please pity the sumacs, which offer food and shelter for birds and bees in summer and winter alike. (Not related to poison sumac.) I’ve watched sumacs of all varieties carried away, roots to the sky and helpless on landscapers’ trucks by the hundreds.

Along the same lines, native sassafras, Virginia creeper, hay-scented fern, ostrich fern and jewelweed get no respect.

Use the pictures here to learn more about native plants that can fill big spaces “like weeds” and why we should think twice or three times before removing them.

Note that these vigorous natives need no care once established and are very deer-resistant. Maybe it’s time to love — not loathe — some plants that can out-compete the weedy invaders from other parts of the globe that are all too common today.

Kathy Connolly is a writer and speaker from Old Saybrook with a specialty in landscapes, land care and plants. Reach her through her website, speakingoflandscapes.com.

Native moutain mint (Pycnanthemum muticum) does double-duty by suppressing weeds along a driveway while supporting pollinators.

A stand of young sassafras (Sassafras albidum) takes over where mugwort once grew. Sassafras is larval host to several moths and butterflies, including spicebush swallowtail and Promethea silkmoth. The small tree is easily identified by its mitten-like leaves.

Wild bergamot (Monarda fistulosa) delivers a soft pink blush during early- to mid-summer. An aggressive spreader, it increases its footprint every year. This plant has special value to bumblebees, hummingbirds and butterflies.