
I was thrilled to learn recently that the native rose mallow, Hibiscus moscheutos, is returning to the shores of the Charles River! This plant is reclaiming space once taken by the invasive purple loosestrife. Now that the release of a beetle that eats the loosestrife has been successful in our area, native plants like this can return to their proper niches.
You may also encounter this plant in coastal situations such as along the margins of a salt marsh pond. I even saw a clump at a mailbox at the Rhode Island shore last summer.
You can’t miss this plant – it has pink or white flowers up to 6″ wide and will be 6 to 7 feet tall, growing in large clumps. Horticulturists have made selections over the years for home gardens, with slightly shorter cultivars like ‘Ballet Slippers’ and ‘Vintage Wine’ now in the marketplace.
To be successful at home with rose mallows, you need good air circulation, full sun, and moist well-drained soil. Sorry, this isn’t a drought tolerant plant. The hibiscus sawfly and Japanese beetle can quickly find stressed plants and devour the leaves. We control this problem with an early spray of Neem oil.
Since the hibiscuses bloom in late summer, they emerge late from the ground. I cut the stems high in fall to mark the spot. Allow plenty of space around the plants. And if you canoe or kayak the Charles River in Dedham, Needham or Newton please be on the lookout for the stands of native rose mallow!