By Jim Lakin, MD, Master Gardener
“I just hate to see goldenrod blooming. My eyes and nose itch. I sneeze like crazy…” I’ve often heard this complaint, wrongly hurled at a beautiful and ecologically important group of native plants. The problem is these late-summer blooming beauties unfurl their golden flowers at the same time that the relatively inconspicuous ragweed releases its allergy-causing pollen into the air. It is ragweed pollen, not the flowers of goldenrod, which creates all the misery of fall hay fever season. (Read this month’s “Gardener Beware” article for more on ragweed and hay fever.) Unlike ragweed which is wind-pollinated, goldenrod is dependent upon visiting insects to spread its pollen from plant to plant. Consequently, goldenrod produces abundant, nectar-rich flowerings to attract the pollinators. It thus is a very important source of late-summer and fall nectar for these vital insects, when little else is available, save for the asters.
So, if goldenrod is so great why don’t we see it more in gardens than in vacant lots? As you might expect there is some debate as to whether or not goldenrod is a native plant to be cherished or a common weed to be eradicated. When you get right down to it, that’s a pretty subjective decision. One man’s weed is another’s treasure. Most goldenrod is leggy or “weedy”. They can be pretty aggressive spreading by seed and underground rhizomes. They will take over from less robust plants. Therefore, you have to be careful where you plant them. Some folks consider them “inappropriate” for formal garden settings. So, if your home turf is severely suburban, your neighbors might look askance at a front lawn patch of goldenrod.
As you’ve probably guessed, my own aesthetics are a bit more on the wild side. I find Solidago sp. a great addition to fall landscape color in our wooded acreage. They are great for tough spots where most other perennials are reluctant to grow. They attract a variety of butterflies and bees in late August and September. Their seed heads are an important source of nutrition for birds during the winter months.
Now that you’re ready to get in the goldenrod game, here are a few of my favorite species:
- Zigzag Goldenrod (Solidago flexicaulis) is very hardy, reaching 1 to 2 feet. And yes, its stem does grow in a zigzag pattern.
- Bog Goldenrod (Solidago uliginosa) will grow in areas with wet, boggy soil although is prefers good drainage. It gets 3 to 5 feet tall.
- Old field Goldenrod (Solidago nemoralis) only grows ½ to 2 feet in contrast to its taller cousins.
All goldenrods prefer full sun but will soldier through light shade. They have very few natural pests and really don’t require fertilization on all but the poorest soils. A little fertilizer or compost in the spring will boost their height. You should water newly planted goldenrod weekly. In subsequent years they get by with help only in the driest periods of summer. As I said, Solidago can spread. Planting it in a confined bed will help. Some folks suggest digging it up every couple of years before the roots become established. Another suggestion is to deadhead the flowers before they form seed, although this deprives birds of a vital food source in winter and early spring.
So, if you are up to a little naturalization, Solidago is the thing. The birds and the bees will thank you.