Maine gardener: Sixty-three plant species could be banned for sale under new state proposal

Under a proposed list of plant species that could become illegal to import or sell in the state, the Mainers would lose some popular landscape plants – but that’s probably a good thing.

Several very popular trees, shrubs and perennials feature on this list of 63 species. Many others, however, I had never heard of before.

The stakeholder committee tasked with proposing which plants to ban plans to finalize its list on Jan. 18, according to state horticulturalist Gary Fish. The new list will be added to the 33 forbidden plants about five years ago. The state prohibits the sale and import of plants that spread quickly and supplant native plants, which over millennia have co-evolved with native wildlife to provide essential food and shelter.

The Rugosa rose, the fragrant beach rose widespread all along the coast and very popular in gardens in Maine, is included. The other species on the list as it stands are wisteria, vinca (aka periwinkle), Japanese lilac, Callery or ‘Bradford’ pear, Buddleia davidii (aka butterfly bush), hardy kiwi and Spirea japonica; the latter includes the popular cultivar “Magic Carpet”.

When I interviewed Fish last summer, shortly after the committee – which is made up of professionals from the landscape industry – began its work, he predicted that the rugosa rose would not make the list. I wondered what had changed.

“I think it’s because a few new (scientific) papers have been published on rugosa roses appearing on islands off the coast of the Netherlands,†Fish said.

The Rosa rugosa are native to Asia. They were introduced to America in the mid-19th century, during the Civil War era. As it turns out, rose hips – the orange-red fruit that contains the plant‘s seeds – fell into the ocean and floated long distances to form colonies on islands. Botanists along the coast of Maine and in Canada have also reported such a spread.

And Fish noted that the Maine Natural Areas Program, a state conservation program that the committee relies on for its list of prohibited plants, has long considered the rugosa rose to be a highly invasive plant.

The fish have designated Japanese lilac as another plant on the proposed list that is a regular seller at local nurseries. The arboreal lilac is related to but different from the common lilac found in the gardens of many people, which is native to Europe and is not affected by the ban.

Buddleia also sells well in Maine, but don’t be confused by its common name, butterfly bush. Buddleia is not related to Asclepias tuberosa, the butterfly weed, native to Maine and host to monarch butterflies, whose numbers are in sharp decline.

I was surprised to find periwinkle, or vinca minor, on the list. Decades ago, my wife Nancy and I planted the white and purple flowering versions of the ground cover and have even recommended it in this column as a good ground cover. We had to cut it on occasion to keep it from spreading over our lawn, but we haven’t seen it sow long distances from where we planted it. But, as I’ve learned about unrelated topics over the past couple of years, we have to trust the science.

Another point: the rules for the 33 original plants and the 63 additional species proposed only prohibit the sale or import of the plants. Homeowners who already grow them in their gardens are not required to dispose of them. That said, the withdrawal might be something to consider.

Early on, the stakeholder committee made the decision to exclude “hitchhiker plants†from the list, Fish said. If it had included them, the list would have expanded to 30 more species. Nurseries do not intentionally sell so-called hitchhiking plants; on the contrary, they appear in the ground with the plants that customers intend to buy.

After the committee votes on Jan. 18 on a final list, the proposal will be made public and the 30-day public comment period will begin. The list will then go to the commissioner of the Ministry of Agriculture, Conservation and Forestry and the Attorney General’s office, so that they can approve the language.

The new regulations, once finalized, provide for a transition period of one or two years so that nurseries can sell any newly banned plants they have. To enforce the bans, state horticultural assistants visit all commercial outlets selling plants during a year. Enforcement of the existing law has not been problematic, Fish said. A few chain stores sold euonymus (burning bush) and honeysuckle, but the plants were removed.

I’ve gone through the entire list of plants that would be banned under the new proposal, and I don’t think gardeners in Maine will suffer from not being able to use them. Many gardeners turn to native plants anyway. And there are many non-natives without harmful side effects.

Tom Atwell is a freelance writer who gardens in Cape Elizabeth. He can be contacted at: [email protected]

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