Ornamental · Asteraceae
Goldenrod
Solidago canadensis
Give it full sun and lean soil, and goldenrod lights up the late-summer garden and feeds every pollinator around.
Full sun
Every 7–14 days
USDA 4–9
2–6 ft · 0.6–1.8 m
Overview
Goldenrod is the plant that sets fields and roadsides ablaze in late summer, with plumes of tiny gold flowers carried on tall, leafy stems. It belongs to the aster family and grows wild across most of North America as a tough, long-lived perennial. In the garden it asks for almost nothing and pays you back with weeks of color when most other flowers have faded.
Few plants do more for pollinators. The flowers swarm with bees, butterflies, and beneficial insects right when food is scarce, and the seedheads carry birds through the cold months. That makes goldenrod a backbone of any planting meant to support wildlife.
The catch is its drive to spread. Tall goldenrod runs through a bed by rhizome and self-seeds with abandon, so it can crowd out gentler neighbors if you let it. Pick a clump-forming species for a tidy border, or plan to divide the vigorous types every few years to keep them honest.
Care
The short version: full sun and ordinary to poor, well-drained soil. Water through long dry spells but otherwise let the rain do the work, skip the fertilizer, and divide vigorous clumps every few years to hold them in bounds.
Light
Goldenrod wants full sun to flower at its best and stand up straight. It will take some partial shade, but the stems stretch and flop and the bloom thins out the less light it gets.
Water
Goldenrod likes soil that stays evenly moist yet never waterlogged, and established plants shrug off short dry spells. In most temperate gardens rainfall carries it, so plan to water only through a prolonged drought.
Soil
It grows in clay or loam as long as the drainage is decent, and it tolerates poor ground that would stall fussier plants. A pH anywhere from 5.5 to 7.5 suits it, and lean soil actually keeps the growth sturdier.
Temperature
Goldenrod is remarkably hardy, taking cold down to -29°F (-34°C) and heat up past 95°F (35°C). That wide range is why it thrives untended across so much of the continent.
Humidity
Average outdoor humidity is all it needs, so there's no figure to fuss over. Air movement counts for more, since still, muggy air is what invites rust and powdery mildew onto the leaves.
Feeding
Skip the fertilizer in all but the poorest ground. Goldenrod thrives on lean soil, and too much nitrogen just grows floppy, weak-stemmed plants, so at most give a light spring topdressing of compost.
Pruning
Cut spent flower stems after bloom, or leave the seedheads standing to feed birds through winter. Take all the stems to the ground in late winter before new growth starts, and a pinch in early summer keeps the tall types from flopping.
Size & spacing
Plants run from 2 to 6 feet (61 to 183 cm) tall and spread 4 to 6 feet (122 to 183 cm) wide, so give a clump real room. That generous spread is also why the vigorous species need dividing to stay in their lane.
When to plant
Goldenrod follows the seasons closely. Start seed in late winter or sow it outdoors in fall, set young plants out in spring once frost has passed, and the flowers come on strong from late summer into the heart of fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Late winter, 8 to 10 weeks before last frost; seeds benefit from cold-moist stratification and need light to germinate
- Plant: Spring after the last frost, or in early fall
- Harvest: Late summer through fall (August to October)
Hardiness
USDA hardiness zones: 4–9
Temperature: down to -34°C
Troubleshooting
Goldenrod is rarely troubled by anything serious, and most of what shows up is cosmetic. Crowding and damp foliage cause the worst of it, so airflow fixes more problems than any spray. Match what you see below and step in only when it bothers you.
Rusty orange pustules on the undersides of leaves
This is rust, a fungus that shows up as raised orange or brown spore blisters that rub off as colored powder. It rarely does lasting harm, but it spreads fastest in crowded, damp clumps. Strip off the worst leaves, thin or divide the plant for better airflow, and water at the base rather than over the top.
Fix:
- Remove and destroy heavily infected leaves
- Improve air circulation by thinning or dividing crowded clumps
- Avoid overhead watering and water at the base
A white dusty film coating leaves and stems
Powdery mildew lays a gray-white film over the leaves, usually late in the season when nights turn humid or the plant sits in shade. It looks worse than it is and seldom kills an established clump. Cut back the coated foliage, open the plant up to more sun and air, and clear away the debris before winter.
Fix:
- Cut back affected foliage
- Increase spacing and sun exposure to improve air movement
- Remove infected debris at season end
Tiny insects massed on stem tips with a sticky film
Soft-bodied aphids gather on the new growth and flower buds, leaving behind sticky honeydew that often draws ants. Goldenrod feeds a long list of beneficial insects, so a light infestation is worth tolerating. Knock heavier clusters off with a sharp jet of water, and reach for insecticidal soap only if they refuse to quit.
Fix:
- Spray off with a strong jet of water
- Tolerate where possible since goldenrod supports many beneficial insects
- Use insecticidal soap only if infestation is heavy
Round or spindle-shaped swellings along the stems
These are galls, formed when the goldenrod gall fly lays an egg and a larva develops inside the stem. They rarely hurt the plant and they feed birds and other wildlife through winter. Prune the galled stems out if the look bothers you, but otherwise it costs you nothing to leave them be.
Fix:
- Prune out and discard galled stems if appearance is a concern
- Otherwise leave in place as galls rarely harm the plant and feed wildlife
Toxicity
Goldenrod is safe all around, with no part of it toxic to people, pets, or livestock. It carries the old blame for hay fever, but that belongs to ragweed instead. You can plant it freely where children and animals roam, and even brew the leaves into a herbal tea.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Goldenrod is safe around cats, with nothing in the leaves or flowers that harms them. A curious nibble might bring a brief, mild stomach upset, the same as with any plant a cat isn't built to eat.
Dogs None
Dogs can be near goldenrod without any worry, since it carries no toxic compounds. At most, a dog that gobbles a big mouthful of foliage might drool or pass it a little loose, which settles on its own.
Horses Safe
True goldenrod is safe for horses and turns up in many pastures without trouble. It is not the toxic lookalike sometimes confused with it, so grazing alongside it poses no danger.
Rabbits Safe
Rabbits can browse goldenrod safely, and wild ones often do. The leaves and flowers hold no toxins, though as with any new green it is best introduced in small amounts.
Livestock Safe
Cattle, goats, and sheep can graze around goldenrod without harm. It is not toxic to them, and they tend to pass it by in favor of more tender forage anyway.
Birds Safe
Birds are in no danger from goldenrod and in fact gain from it, feeding on the seeds and on the insects its flowers draw. Nothing about the plant is harmful to them.
People Safe
Goldenrod is safe for people, and its leaves and flowers have a long history of use as a herbal tea. It does not cause hay fever, despite the old reputation, because its heavy pollen never blows on the wind.
Varieties
Goldenrod is not one plant but a whole genus, and the species vary widely in size and manners. These are the ones most worth knowing before you plant.
Solidago rugosa 'Fireworks'
A compact selection of 3 to 3.5 feet that throws out arching sprays of tiny flowers like a burst of fireworks, and it spreads by rhizomes without turning invasive.
Solidago canadensis
The vigorous tall species, reaching 2 to 6 feet with broad pyramidal flower heads, and it spreads fast by both seed and rhizome.
Solidago speciosa (Showy goldenrod)
An upright clump-former that does well in poor, dry ground and stays far better behaved than the tall goldenrod.
Solidago caesia (Bluestem/wreath goldenrod)
A woodland goldenrod with bluish arching stems that carries its flowers in the leaf axils and takes shade in stride.
How to propagate
Goldenrod multiplies with little effort, whether you split an existing clump or start fresh from seed.
DivisionEasy
Spring or early fall; divide established clumps every 2 to 3 years to control spread and maintain vigor · One growing season
Division is the simplest way to make more goldenrod and to keep a clump in check. In spring or early fall, lift the plant, split it into sections that each carry roots and shoots, and replant them right away. Done every 2 to 3 years, it keeps the clump vigorous and settles back in within a single growing season.
SeedEasy
Sow in fall outdoors or stratify and start indoors in late winter · Blooms typically in the second year from seed
Goldenrod grows easily from seed, though it asks for patience and a little light. Surface sow in fall outdoors, or stratify and start the seed indoors in late winter, but never bury it, since the seed needs light to sprout. Plants usually flower in their second year, and they self-seed freely once established.
Myths
Goldenrod causes hay fever and seasonal allergies.
Goldenrod pollen is large, sticky, and heavy, so insects carry it from flower to flower and it almost never drifts on the wind. The real culprit behind late-summer sniffles is ragweed, which blooms at the same time and throws off clouds of light, wind-borne pollen. Goldenrod just happens to be the showy plant standing nearby when people start to sneeze.