Goldenrod can be seen blooming in ditches along roads and highways throughout the countryside during autumn. A lovely wild perennial, it is a true harbinger, and when goldenrod first makes its appearance we know fall — and harvest season — are fast approaching. There are several varieties of native goldenrod and each has a slightly different bloom time so ditches in our region are full of colour for at least two months, because as one variety finishes flowering another starts.
Wild goldenrod is a bit too unruly to include in a domestic planting unless used in a large rural property in a naturalized way. It is fairly invasive and will overtake other perennials when included in a flower border. Goldenrod is a wonderful addition to a wildflower garden or a naturalized meadow in a large rural landscape, but is too invasive for a small landscape. In a rural property it can be planted along the side of a machine shed or other outbuilding, or near the edge of a dugout or pond to provide colour.
Plant breeders have developed domestic cultivars of goldenrod that are better suited for use in flower borders even in small urban landscapes. These will still self-seed to some degree unless they are deadheaded and they are somewhat invasive in a border, but are more clump forming and less invasive than native varieties. Carefully managed, domestic goldenrod (its horticultural name is “Solidago”) can be controlled and confined to its intended spot. The plants have the same lovely golden flowers, strong, self-supporting stems, and toughness as their native cousins. Although goldenrod used to have a reputation as the cause of hay fever, this idea has been discredited, as grains of pollen are large and sticky and require insects to move them from flower to flower so it is not windborne, and not a major cause of hay fever.
Most of the domestic varieties are a bit shorter than the native ones, which make them more suitable for use as a landscape plant. Often goldenrod is labelled “Solidago” in greenhouses, but the cultivar name, such as “Golden Baby” or “Early Bird,” could also appear on the tag.
Goldenrod is useful to have in the landscape because it attracts pollinators — especially bees. Solidago is a tough, resilient plant, and although versatile and adaptable, it does require lots of sunlight. If the plants are exposed to too much shade they will be elongated and the stems will become weak and may not be able to support the heavy heads of bloom. Like many plants derived from native plants, goldenrod is not usually susceptible to disease or insect attacks. Some stems might develop swellings (called galls) but other than being somewhat unsightly, they are simply an indication of the plant’s defence system. If the plant is attacked by an insect it grows a gall which surrounds the offending culprit, thereby stopping the attack. Wasps and birds use these galls for their benefit. Wasps lay eggs in the galls where the resulting larvae feed on the encased insect while birds simply peck into the galls to feed on the insects inside.
Most goldenrod cultivars are quite tall — easily reaching a height of one metre — making the plant a good choice for the back of the border where it can serve as a background for shorter ones. It is drought tolerant and “Solidago” is not at all fussy about soil type. Good companion plants include heliopsis, sage and veronica, tall monarda, verbascum and lilies. “Solidago” can also be mass planted to create a wonderful show of golden bloom in the fall, and gets rid of the need to contain them to prevent them from becoming too invasive.
Goldenrod makes a great cut flower with a long vase life. I often use it as filler in fresh flower arrangements for horticultural shows and it can be added to a bouquet of mixed garden flowers. Its fluffy golden flower heads combine well with the rather stiff spikes of gladioli, which are often in bloom at the same time.
Stems of goldenrod can be air-dried simply by tying several stems together and hanging them upside down in a dark airy place, perfect for use in dried flower creations.
Goldenrod is a useful and versatile plant in the landscape. Consider whether it would be a good candidate for your garden.