Master Gardener Ann Bartlett discusses the differences between two early fall bloomers, goldenrod and ragweed.
One can debate whether goldenrod is a weed or a wildflower, but one thing is for sure—it does not cause seasonal allergies. Goldenrod’s pollen is too heavy and sticky to be blown about by the wind. This plant got a bad reputation because the insignificant flowers of ragweed bloom at the same time as showy Solidago (pronounced sol-ih-DAY-go).
Goldenrod Ushers in Autumn
Hardy from USDA cold hardiness Zone 3 to Zone 9, goldenrod is a wide-ranging North American native plant. Wild ones reproduce by underground rhizomes as well as seed, crowding out other species. These prairie and meadow-loving plants are four to five feet tall and just as wide. Unless you have a large, sunny, naturalized area where they can spread at will, they are not at home in the garden.
Goldenrod plants are valued for their late summer to early autumn golden-yellow flowers that bloom along curving racemes or spike-like panicles. Plant hybridizers have tamed some for the garden. They are deer-resistant, and they attract butterflies and bees. Goldenrods require a sunny, well drained site and they are tolerant of a wide range of soils, including clay.
Native Americans chewed the leaves of goldenrod to treat toothaches and brewed a tea of the leaves to soothe sore throats. More modern herbalists use wild goldenrod to treat kidney problems.
Ragweed Dies at First Frost
Seventy-five percent of allergy sufferers are sensitive to ragweed, and our nation is home to seventeen species of this pollen-packed plant. Ragweed blooms from August into November, with pollen counts peaking in mid-September. In the most southern tier of states, they are thought to bloom most of the year. Here in Tennessee, Jack Frost wipes out these noisome annuals.
Although I enjoy seeing sunny Solidago along the roadside, I am not fond of it in a border. It is not bright enough for me, and it is nothing when not in bloom. When it comes to ragweed, I sneeze with the seventy-five percent waiting for frost to bring relief.