Hawkweed (Hieracium spp.) - How to Grow & Care Guide

Plant Snapshot

Common Name: Hawkweed
Latin Name: Hieracium spp.
Hardiness Zones: USDA zones 3–8 depending on species. Colder zones may show winter dieback to roots. Warmer zones can support larger colonies and more persistent growth.
Typical Height: 6–24 in (15–60 cm) tall depending on species
Typical Spread: 6–24 in (15–60 cm) per plant or in colony form; some species form wider mats by runners
Bloom Period: Late spring to mid summer in temperate Northern Hemisphere, commonly May–July
Soil Preferences: Prefers well drained loam to sandy soils. Tolerates poor rocky or low fertility soils. Heavy wet soils are generally problematic and reduce vigor.
Light Preferences: Full sun to partial shade. Flowering and spread are best in sunny sites.
Toxicity: Not widely reported as highly toxic to people or pets but ingestion is not recommended. Some species or plant parts could cause mild stomach upset or skin irritation in sensitive individuals.
Propagation: By seed and by division. Several species also spread vegetatively by stolons or short rhizomes and can be propagated from rooted runners.

Key Facts

A genus of herbaceous plants in the aster family
Flower heads resemble small dandelions or daisies
Many species form groundcover mats or loose colonies
Spreads by seed and by vegetative runners in some species
Includes species regarded as invasive in parts of North America and elsewhere
Prefers well drained soils and open sunny sites but tolerates poor soils
Typical bloom time is late spring into summer in temperate climates
Propagated by seed, division, and stolons or rhizomes in some species
Not widely listed as highly toxic but ingestion is not advised

Hawkweed (Hieracium spp.) is a group of low to medium height flowering plants in the aster family that often form rosettes or mats. They give bright, dandelion like flower heads and can make quick groundcover while some species are regarded as invasive in parts of North America.

Identification

Flower heads look like small dandelions or daisies and appear from late spring into mid summer, commonly May to July in temperate climates. Plants range about 6 to 24 inches tall and individual plants or colonies commonly span 6 to 24 inches across. Many species form basal rosettes and some spread by stolons or short rhizomes.

Where to grow and best uses

Grow hawkweed in full sun to partial shade. It prefers well drained loam to sandy soils and tolerates poor rocky or low fertility sites. Use hawkweed as a low growing groundcover on sunny slopes and dry soils or in wildflower mixes where a spreading, low maintenance carpet is desired. Note that some species spread aggressively and can displace nearby plants.

Planting and spacing

Space plants roughly 6 to 24 inches apart depending on the species and how quickly a colony is wanted. Propagate by seed and by division. Several species also root from stolons or short rhizomes and can be established from rooted runners.

Timing and propagation

Bloom usually occurs in late spring into mid summer. Propagate by sowing seed or by dividing established clumps. Vegetative runners produce new rooting points and make division or runner removal the fastest ways to expand or control a patch.

Watering and soil care

Keep soil well drained. Heavy wet soil reduces vigor and can lead to poor performance. In dry, sunny sites hawkweed stays compact and flowers more freely. It tolerates low fertility so avoid overfertilizing which encourages floppy growth in some species.

After flowering and maintenance

Remove spent flower heads to limit reseeding. Divide crowded clumps to refresh plants and to reduce spread. Hand pulling young seedlings and removing runners helps control expansion before colonies get large.

Controlling spread and invasive risk

Several hawkweed species are considered invasive in parts of North America and elsewhere. Verify local status with your extension service before planting. To contain hawkweed remove flower heads, dig out runners and young crowns, and monitor the site for seedlings in the first few seasons.

Toxicity notes

Hawkweed is not widely listed as highly toxic but ingestion is not advised. Some people may get mild stomach upset or skin irritation. Consult poison control or a veterinarian for exposure concerns.

Frequently asked questions

How fast does Hawkweed grow?: Growth rate varies by species and site. Many form colonies by seed and runners and can expand quickly in sunny well drained conditions.
Will Hawkweed come back after winter?: Hardiness varies by species. At the genus level hawkweed is commonly hardy in USDA zones 3 to 8 and colder sites may show winter dieback to the roots.
Can I remove hawkweed by hand?: Yes. Pull young plants and dig out stolons and crowns. Consistent removal of runners and seed heads reduces spread over time.
What soil does hawkweed prefer?: It prefers well drained loam to sandy soils and tolerates poor rocky or low fertility soil. Heavy wet soils tend to reduce vigor.
How do I propagate hawkweed?: Propagate by seed and by division. Several species also spread vegetatively by stolons or short rhizomes and can be propagated from rooted runners.