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How to Grow Hieracium Plants in your Garden

Gardener's HQ Guide to Growing Hawkweed, Devil’s-paintbrush, and Hierakion.

Hieracium consists of a large genus of hardy perennials.

They are weedy and woody in nature and some species have an attractive silvery foliage.

They bloom from late spring through to autumn with orange or yellow flowers that are similar to those of dandelions.

They reach heights of 30 to 40 cm (12 to 16 inches), making them a bigger plant for use in a rock garden.

Some of the common species of Hieracium plant used by gardeners include Hawkweed and devil's Paintbrush.

Hieracium pilosella
Hieracium pilosella by urjsa.

Hieracium Plant Growing and Care Guide

Common Names: Hawkweed, Devil’s-paintbrush, Hierakion.
Life Cycle: Hardy perennial.
Height: 12 to 18 inches (30 to 45 cm).
Native: Worldwide except Australasia and Antarctica.
Growing Region: Zones 3 to 9.

Flowers: Species dependent: Late spring through to the autumn.
Flower Details: Orange, yellow. Dandelion-like. Spatulate.
Foliage: Silver/grey. Very varied.

Sow Outside: Cover seed. Start of spring - before the last frost, or towards the end of autumn. Spacing 10 to 12 inches (25 to 30 cm).
Sow Inside: Germination time: three weeks to a month. Temperature: 50 to 60°F (10 to 16°C). Two months in advance. Transplant outdoors the last frost, or late in autumn.

Requirements and care: Full sunlight. Good drainage. Poor soil. Can survive in dry soils. Most species need to be controlled so remove flower-heads before they can set seed; as garden grown varieties of this genus, such as H x rubrum are usually grown for their foliage it may be a good idea to remove any flowers completely.
Miscellaneous: Most members of this genus are weeds and invasive, but the odd variety can be used with caution in a rock garden. The scientific name is based upon the From the Greek word for hawk (Hierax).

How to Grow Hawkweed and other Hieracium Plants in the Garden

When growing Hawkweed and other Hieracium plants in the garden, it is important to realise that they can fast become weeds. So only grow if you have the time to maintain them properly. This will require removing flower heads before they have a chance to set seed.

Hawkweed seeds should be sown into a sunny part of the garden before the last frost of early spring. Simply cover the soil once sown.

Hieracium can grow in poor soil, and has a preference for a dry soil with good drainage.

You may find it easier to have control of Hawkweed if you start them off as seedlings indoors.

They should be prepared about two months before they are due to be transplanted in the spring, before the last frost.

Hieracium plants take about three or four weeks to germinate at a temperature of 10 to 15 degrees centigrade (50 to 59°F). Plant out at a spacing of about 25 cm (10 inches).

Caring for Hieracium plants

Once growing, it is very important to keep an eye on the Hieracium plant to prevent spreading. Remove all Hieracium flowers before they have a chance to set seed.

Common Questions

How many members does the Hieracium genus have?

The Hieracium genus, commonly known as hawkweeds, includes about 800 species (possibly over 1,000 dependent upon classification), characterized by their daisy-like flowers.

Do members of Hieracium make a good garden or landscaping plant?

While some gardeners may appreciate the bright flowers of Hieracium, many species can be quite aggressive, spreading quickly and overtaking desired plants.

Which Hieracium species are most frequently grown by gardeners?

Among the hawkweeds, Hieracium aurantiacum or orange hawkweed is sometimes grown for its vivid orange flowers.

Are members of the Hieracium plant genus fragrant?

Hieracium species are not known for their fragrance, but for their bright, daisy-like flowers.

What is the perfect location to grow Hieracium?

Hieracium species can tolerate a range of conditions, from full sun to part shade, and prefer well-drained soil.

Is Hieracium invasive in the USA, if so in which states?

Yes, some species like the orange hawkweed (Hieracium aurantiacum) are currently considered invasive in several northern states, particularly in the Northeast and the Pacific Northwest.

How do I remove Hieracium plants from my garden?

Removal of Hieracium involves careful hand-pulling or digging, ensuring all roots and stolons are removed to prevent re-growth.

Summary

The Hieracium genus belongs to the Asteraceae family. These perennial herbs are native to temperate regions of the Northern Hemisphere. They are recognized by their dandelion-like flower heads.

Hieracium grows well in a wide range of conditions, but prefers full sun to partial shade and a well-drained soil. Plants are drought-tolerant once established. Propagation is usually done by sowing seeds, sown in the spring or fall.

I hope that you enjoyed this guide on how to grow Hieracium plants. You may also enjoy my gardening guides on how to grow Pineapple flower, Muscari plant, and Cardiocrinum plants.