Goldenrod: flowering time, cultivation & uses

Goldenrod lives up to its name: in late summer, these plants stand out with their stunning golden-yellow blossoms. However, goldenrods are not without their problems, so there are a few things to bear in mind when picking a variety and growing it.

Goldenrods (Solidago) belong to the daisy family (Asteraceae) and are characterised by their lush yellow blossom. The late-blooming goldenrod offers an important source of food for insects, and some amazing medicinal benefits for humans too. That being said, some goldenrod varieties are considered invasive in Europe, and we need to take care when planting them. This article provides an overview of the origins and different varieties of the goldenrod perennial, as well as how to care for it.

Goldenrod: characteristics and origin 

Goldenrod, yellow solidago, hayfever weed and woundwort are some of the many names given to the solidago plant. They are most commonly found in North America. They are perennial, herbaceous plants, reaching heights of between 10 cm and 1 metre. The goldenrod leaves are simple and alternate and just like the stems, can be hairy or smooth. Being a composite plant (Compositae), the flowerhead is made up of lots of small individual flowers. The yellow solidago flowers provide food for insects late in the growing season from August to October.

As a pioneer species, goldenrods appear mainly in drier locations, such as roadsides, fallow land, or water banks, that have been disturbed by human activity. Solidago can be propagated from rhizome cuttings and from seeds.

The most beautiful Solidago species and varieties

If you want to plant goldenrod in the garden, there is a wide choice of goldenrod species and varieties. Here are just a few:

• Common goldenrod (Solidago virgaurea): The European goldenrod is a somewhat smaller, common goldenrod native to Europe. It usually grows to a height of 40 cm and is characterised by loose blossoms, with large flowerheads of between 6 and 10 mm.
• Small goldenrod (Solidago cutleri): As a perennial, growing to a height of 20-40 cm, this variety is particularly suitable for the front of flower beds.
• Miniature goldenrod (Solidago virgaurea var. minutissima): This small-growing cultivar only grows to 10 cm high and works well in small flower beds. Producing about 40 plants per square metre, it covers the ground with a thick, light-yellow carpet. It is not likely to spread out of control.

There are two invasive goldenrod species that we do not necessarily recommend cultivating. The larger and more striking Canadian goldenrod (Solidago canadensis) is one of the widespread neophytes introduced in the 17th century, alongside the giant goldenrod (Solidago gigantea). Both species grow much taller than the common goldenrod, reaching heights of between 50 cm and 250 cm, and produce a variety of much smaller flower heads. The two goldenrod species grow primarily in locations impacted by human activity, such as fallow land and roadsides, but rarely in healthy ecosystems. Since they provide abundant food for insects, the species are certainly seen as beneficial today. Nevertheless, we would not recommend you plant them, as doing so would put pressure on native flora.

Planting goldenrod

As pioneer plants, goldenrods have adapted to extreme conditions and grow well in both nutrient-poor and moderately fertile areas. It is not usually necessary to give the plants any extra fertiliser. If possible, plant your goldenrod somewhere that gets plenty of sunshine. Spring is the best time to sow seeds. Then transplant the hardy perennial outside in spring or Autumn. Goldenrods are not very sociable and prefer to be planted in small groups of three to ten. For tall-growing varieties, the optimum number per square meter is between three and five plants. The smaller the variety, the more individual plants you can put per area.

Tip: You can propagate goldenrod hybrid varieties yourself by division or cuttings. Other varieties and wild species can also be propagated using seeds.

The most important care measures

• September – October: It is best to prune the Canadian goldenrod towards the end of the flowering period, but before the seeds have ripened to prevent an uncontrolled spread.
• March: Other varieties can be pruned in the spring before they bud. Withered goldenrods will enrich the barren garden in winter and provide shelter for insects.
• March – April: Once goldenrods are established in a location, it is recommended to divide the perennials every 3 to 4 years to maintain vibrant and blooming plants. This is also important to help prevent powdery mildew.

Are goldenrods poisonous?

Goldenrods are not poisonous to humans, dogs, cats or rabbits. All parts of the plant are safe to touch and theoretically, goldenrod is edible. Only people with an allergy to plants in the daisy family should be careful when handling the plant.

Goldenrod: effects and uses

During its flowering period, the flower tips can be collected and dried. In addition to common goldenrod, the Canadian goldenrod and the giant goldenrod also have comparable beneficial properties and can be collected.

Goldenrod has been proven to be effective in treating bladder problems, urinary stones, and kidney diseases, by flushing the body of toxins. The goldenrod herb is most commonly prepared as a tea – often in combination with other herbs. This has a diuretic and antispasmodic effect – improved urination stimulates the metabolism.

Tip: To make goldenrod tea, brew 2 teaspoons of dried goldenrod flowers with 250 ml of boiling water. Leave to steep for 10 minutes then enjoy.

Alternatively, you can take a goldenrod tincture. To make it, fill a glass full of freshly cut goldenrod herbs with 70 percent alcohol and close it tightly. After two to three weeks of steeping, the tincture will be ready. For internal use, for example to treat bladder problems, take 20 to 30 drops per day. For minor injuries, the tincture can also be used externally to disinfect small wounds.

Tip: There are also many uses for goldenrod in the garden. An extract of goldenrod flowers can be sprayed on leaves to protect against powdery mildew and blight. To make this, blanch finely chopped goldenrod heads with boiling water and steep for an hour.

Goldenrods are sun-loving perennials. However, if you are looking for a colourful variety of flowers that will still flourish in more shaded parts of the garden, we have put together a list of 10 perennials that also grow in the shade.