Ornamental · Asteraceae
Blazing Star
Liatris spicata
Set the corms once and blazing star lifts tall purple spikes for the bees over the summer garden.
Full sun
USDA 3–8
2–4 ft · 0.6–1.2 m
Overview
Blazing star brings a sense of movement to the summer garden that few other perennials can. In place of the wide, flat flowers of most border plants, it lifts tall, slim spikes crowded with dense purple buds, and a drift of them in bloom turns a quiet bed into a stage for butterflies and bees. Grown from a corm, it returns on its own each year and asks little in exchange, which makes it an effortless anchor for a low-maintenance planting.
Its charm peaks at bloom, and it arrives with a small surprise. Where most spike flowers open from the bottom up, blazing star opens from the top down, so the crown softens as the base comes into color. Those grassy leaves and upright stems lend a border the vertical rhythm it needs against rounder, softer companions, whether you plant the full-height species for the back of the bed or a shorter selection like 'Kobold' toward the front.
It settles happily into any sunny, well-drained corner and pairs beautifully with a relaxed, hands-off routine. Give it full sun and ground that drains, and it carries heat, drought, and even poor soil in its stride once its roots are down. The single thing to avoid is a low, wet spot in winter, which rots the corm faster than any pest or disease.
Care
The short version: a sunny, well-drained spot suits it best, with regular water the first season and far less after, and never a corner that stays soggy through winter.
Light
Give blazing star full sun and it repays you with poise. It manages in partial shade, but there the stems stretch and soften and begin to lean, so the more light it takes, the straighter and more composed it stands in the bed.
Water
Water it steadily through the first growing season while the roots find their footing. After that it turns fairly drought tolerant and needs little from you, preferring to run dry rather than sit wet, above all through the winter.
Soil
It takes almost any well-drained soil, from loam to sand to clay, and shrugs off poor ground. A pH anywhere from 6.0 to 8.0 suits it, so drainage, not richness, is the one detail worth minding when you choose its spot.
Humidity
Ordinary outdoor air is all it asks, with no target to chase. Good airflow matters far more here, since a crowded, still corner is exactly where powdery mildew and rust take hold.
Feeding
This lean-soil prairie native is not a heavy feeder, and it looks best when you resist the urge to indulge it. A light feeding before growth begins in spring is plenty, since extra fertilizer only draws out soft, floppy stems that cannot hold their flowers up.
Pruning
Cut the spent flower stalks once they fade, but leave the foliage and hollow stems standing through winter to shelter native bees and feed songbirds, then cut them back in early spring. Tall stems in rich, moist soil may want a discreet stake.
Size & spacing
Plants rise 2 to 4 feet (60 to 120 cm) in a slim, upright clump. Set them about 12 to 15 inches apart so air moves freely and each spike has room to hold its line.
When to plant
Blazing star is a dependable perennial for zones 3 to 8. Set the corms or young plants out in early spring, or plant container-grown stock again in early fall, and the flower spikes rise to lift the garden in mid- to late summer.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Early spring; seed germinates in 20-45 days and benefits from 4-6 weeks cold moist stratification
- Plant: Plant corms or container plants in early spring; container-grown plants may also be set out in early fall, spaced 12-15 inches apart
- Harvest: Blooms mid- to late summer (July-August), with dense purple flower spikes opening from the top down
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Blazing star asks very little and rarely disappoints, and the few problems it does meet nearly always trace to one thing: ground that holds too much water. Keep a casual eye on the stems and leaves as the season turns, and step in early before a touch of fungus or a soggy corm undoes the display. Match what you see below, then act while it still counts.
A planting that suddenly wilts and collapses
When a clump caves in overnight, the trouble is stem and corm rot, which sets in on wet, poorly drained ground, most often soil that stays sodden right through winter. A rotted plant is past saving, so lift it out with the tainted soil around it. The lasting answer is placement: reserve the well-drained corners of the garden for blazing star and skip the low, wet ones.
Fix:
- Improve drainage and avoid wet sites
- Remove and discard affected plants and surrounding infected soil
Tall flower stems leaning out of the border
When the vertical lines you planted for start tipping sideways, the cause is usually soft, overfed growth from ground that runs too rich or too damp, and a shaded corner makes it worse. Shift the planting into full sun and leaner soil, slip a discreet stake behind the tallest stems, or choose a tidy cultivar like 'Kobold' that keeps its poise on its own.
Fix:
- Stake or provide support for tall stems
- Site in full sun and average, well-drained soil rather than rich, moist beds
- Choose compact cultivars such as 'Kobold'
A dusty white bloom dimming the foliage
A pale, powdery haze that mutes the planting late in the season is powdery mildew, a fungus that moves in where plants stand shoulder to shoulder and the air hangs still. Give the clump some elbow room by spacing or thinning it, and clear away the worst leaves so the display keeps its clean, upright look.
Fix:
- Improve air circulation by spacing and thinning plants
- Remove and dispose of badly affected foliage
Rusty flecks marring the lower leaves
Raised, rust-toned spots hiding on the undersides of the leaves are the work of rust fungi, and they can spoil an otherwise crisp planting. Clip and bin the marked leaves before the spores travel, and open the arrangement up so air circulates and the foliage dries quickly once the rain passes.
Fix:
- Remove and destroy infected leaves
- Improve spacing and air circulation
Toxicity
A welcome note for homes with pets or children: blazing star is safe throughout. The ASPCA lists it as non-toxic to cats, dogs, and horses, and nothing in the leaves, stems, or corms will poison people or grazing animals. At most, a large mouthful brings a passing stomach upset and no more.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
For the cat that shares the sunroom, the ASPCA lists blazing star as non-toxic, so a curious nibble need not disturb the peace. Should a cat overindulge on any plant it may bring it back up, but that traces to the coarse leaves, not to poison.
Dogs None
The household dog is on equally safe ground, since the leaves, stems, and corms carry nothing toxic. A large, opportunistic mouthful might bring a brief spell of mild stomach upset and little more.
Horses None
Horses can graze alongside a blazing star planting without concern, as it holds nothing poisonous to them.
Rabbits None
Rabbits and other small companions may browse the foliage in safety, fitting for a wildflower they would meet across any meadow.
Livestock None
Cattle, goats, and sheep come to no harm from blazing star in the paddock, since it carries no toxins to trouble grazing animals.
Birds None
Birds are at ease around it, and songbirds such as goldfinches make a habit of visiting the ripe seed heads through fall and winter, a quiet pleasure to watch from indoors.
People None
No part of blazing star poses any danger to people. It earns its place for the flowers rather than the table, so there is no call to eat it, though a stray touch or taste does no harm at all.
Varieties
The named blazing stars are chosen for flower color or for a more refined, manageable height. These are the selections you are most likely to find on offer.
Kobold
A compact, deep-purple selection that keeps itself upright, making it the natural choice for the polished front edge of a border.
Floristan White
A white-flowered form beloved for cutting, its clean spikes holding their elegance for days in a vase on the table.
Floristan Violett
A violet-flowered selection with stems firm enough to cut and carry indoors, which is why it turns up so often in floral work.
Alba
A pure white form that settles at around 18 inches, shorter than the species and easy to work into a small, considered bed.
How to propagate
There are two graceful ways to bring more blazing star into the garden, by splitting an established clump or by starting from seed, though one rewards you with flowers far sooner than the other.
DivisionEasy
Spring, just as leaves emerge · Establishes over one to two seasons; clumps can be divided every few years
Dividing an established clump is the surest way to carry a favorite planting into other corners of the garden. In spring, just as the leaves begin to rise, lift the clump and part the corms and tuberous roots by pulling or cutting, leaving at least one eye on each piece. The new divisions come up true to the parent, though they take a season or two to settle and fill their place.
SeedModerate
Early spring indoors or direct sow, or fall sow outdoors · Seedlings typically bloom in their second or third year
Seed is the slower, more patient route to a planting. It sprouts in 20 to 45 days, but only after a cold spell rouses it, so give the seed 4 to 6 weeks of cold, moist chilling or simply sow it outdoors in fall and let winter do the work. From there a seedling waits until its second or third year before it offers its first flower spike.
Myths
Blazing star is poisonous to dogs and cats.
This worry can be set aside, since the ASPCA counts blazing star among the plants that are not toxic to dogs and cats. As with any plant, a pet that eats a large mouthful might feel a mild upset stomach, but there is no poison waiting in the border.
Liatris spikes open from the bottom up like most spike flowers.
Blazing star quietly upends the habit of nearly every other spike flower. It blooms from the top of the spike downward, so the crown is already softening while the lowest buds are only beginning to open, a graceful bit of theatre in the summer bed.