Goldenrod Plant Profile

Don't Blame It for Fall Allergies

Goldenrod
David Beaulieu

Goldenrod is a source of mild debate in the plant world. Some say this plant is a type of wildflower, while others deem it an invasive weed. The answer is actually a matter of opinion and growing it in your yard is personal preference. Goldenrod is an attractive plant only when in bloom, and its stalk and leaves have a "weedy" look to them. Its bloom time varies from midsummer to late summer through fall, depending on the variety. For some, the beautiful two to three-month show is enough of a pleasure to earn it a spot in their wildflower garden. But allergy sufferers beware, goldenrod's pollen (as with the pollen of most flowers) is said to be a common allergen.

There are many species of this herbaceous perennial. But generally speaking, this plant is tall and slim (occasionally growing as high as 10 feet tall) with fluffy, golden flower spikes. Most likely, the origin of goldenrod's common name refers to both the flower's color and the plant's spindly presentation. The genus name comes from two Latin words: solidus (meaning "whole") and ago ( meaning "make"). In a medicinal sense, this plant can "make you whole," as the name alludes to its uses as both an anti-inflammatory and a diuretic. 

Botanical Name

Solidago canadensis

Common Name

Canada goldenrod, common goldenrod

Plant Type

Perennial

Mature Size

Over 5 feet tall

Sun Exposure

Full to partial sun

Soil Type

Well-drained

Soil pH

5.5 to 7.5

Bloom Time

August to October

Flower Color

Golden-yellow

Hardiness Zones

2 to 8

Native Area

North America

How to Grow Goldenrod Plant

Goldenrod is an opportunist and can quickly overtake a garden. But for those versed in regular maintenance, it can be a true delight to any pollinator garden. Goldenrod is not widely available as seedlings, due to its invasive nature, but propagating from seed is easy.

  1. Buy seed from your local garden center or dry flowers and save seed from plants cut from the road.
  2. In early spring, broadcast the seed onto moist soil in your garden, taking care to cover only those areas where you'd like goldenrod to sprout.
  3. Keep the garden soil moist until sprouts appear, and then let the area dry out between waterings.
  4. Cut down the dead stalks in late fall and compost them. 
  5. Divide and transplant goldenrod in the following spring if you wish to increase your supply of the plant, but be warned that this plant can be aggressive.

Light

Goldenrod craves full sun and makes its best showing late summer. The plant will tolerate a bit of shade, but may not perform as well under such conditions.

Soil

Most types of goldenrod are native to North America, where they grow as wildflowers in pastures and along roadsides. This gives you a good idea of how tough this plant really is, since the soil along roadsides is often poor. In its native region, goldenrod requires little care. The only real requirement for this wildflower is proper drainage, although it's even been known to tolerate clay-like soil.

Water

Water goldenrod moderately when the plant is young and establishing itself. But, once mature and properly located in the landscape, native plants such as goldenrod need very little care. The plant should thrive alongside other drought-resistant plants.

Temperature and Humidity

Goldenrod can thrive in almost any climate that has ample sun. A slight variance in air humidity and or dryness will not affect its growing conditions. Goldenrod craves mid to late-summer heat and performs best in temperatures ranging from 80 to 86 degrees Fahrenheit.

Fertilizer

Fertilizing goldenrod is not necessary, as the plant grows in the worst soil conditions imaginable. However, if you wish to give your plants a boost or increase their height, fertilize them with organic compost in spring.

Varieties of Goldenrod

There are over a dozen species of Solidago that grow wild in the New England region of the United States alone. Solidago canadensis is especially pretty and very common (hence the name "common goldenrod"). Solidago speciosa is a shorter variety, growing 2 to 3 feet tall, and is so striking that its common name is "showy goldenrod." Other varieties include:

  • Zigzag (Solidago flexicaulis): The origin of its colorful common name lies in the fact that its stem actually zigzags. This variety grows to be 3 feet tall.
  • Old-field (Solidago nemoralis): This plant is on the short side, by comparison to other varieties, and stands 2.5 feet tall. Its flower heads are more cylinder-like, as well.
  • Bog or "swamp" goldenrod (Solidago uliginosa): As its common name suggests, this plant performs best in areas with wet soil.
  • Seaside (Solidago sempervirens): This variety grows by the seashore, as it's a salt-tolerant plant. Its height varies greatly (1 to 8 feet tall) depending on growing conditions.
  • White goldenrod (Solidago bicolor): This type of goldenrod is noteworthy simply because it does not display yellow blooms, but instead flowers in white.

Landscape Uses

Goldenrod is widely known as a plant that attracts butterflies, making it the perfect addition to any butterfly garden. Canada goldenrod, in particular, is a food source for various butterflies, including the monarch, clouded sulfur, American small copper, and gray hairstreak. Goldenrod also attracts a number of other insects, including bees, so adding it to a pollinator garden is a good bet.

Working With Goldenrod's Invasive Qualities

True to its reputation as a weed, goldenrod is an aggressive spreader that may overtake an area, forming a monoculture and preventing the competition of other plants. Therefore, this wildflower is considered an invasive plant outside of its native range. The plant spreads not only by reseeding but also through underground rhizomes. This potent combination accounts for its prolific growth. Less aggressive cultivars do exist, however. Crown of Rays is one such variety.

You can control the spread of goldenrod's rhizomes by planting bamboo barriers around the plant. Another way to control its spread is to transplant it often so that your goldenrod never quite feels "at home." Once it becomes settled in a given area, it will start to spread. To keep goldenrod flowers from reseeding, cut off the flower heads before the seeds develop.