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How to Grow Helenium Plants in your Garden

Gardener's HQ Guide to Growing Sneezeweed, False Sunflower, and Yellow Star

The Helenium genus contains plants that are hardy perennial in nature.

Most garden varieties range between 60 and 120 cm, and have daisy like flowers of red, orange or yellow.

They come into bloom from the end of summer until the first frost. Some common names for members of Helenium include Yellow Star, Sneezeweed, and False Sunflower.

Helenium autumnale

Helenium
Photographs: Helenium autumnale by Wallygrom and Helenium by Lillie2de.

Helenium Growing and Care Guide

Common Names: Sneezeweed, False Sunflower, Rosilla, Yellow Star.
Life Cycle: Hardy perennial.
Height: 12 to 60 inches (30 to 150 cm).
Native: Northern and Central America.
Growing Region: Zones 3 to 9.

Flowers: Middle of summer through to the first frost.
Flower Details: Gold, Orange, red. Daisy-like ray and disc/pin-cushion florets. Multiple flower heads.
Foliage: Herbaceous. Lance-shaped. Oval shaped. Rosette.

Sow Outside: Cover seed. Start of spring or the beginning of autumn. Spacing: Small 12 to 18 inches (30 to 45 cm); Large 24 to 48 inches (60 to 90 cm).
Sow Inside: Germination time: one to two weeks. Temperature: 70°F (21°C). Two months in advance. Transplant outdoors before the last frost or at the beginning of autumn.

Requirements and care: Full sunlight. Best results in with soil pH 5.5 to 7.0 and rich soils, will grow in most soil types. Delay flowering by pinching back in spring. Water during dry periods to maintain soil moisture. Provide support with twigs. Regular deadheading. In autumn cut back to ground level. Requires to be divided every three years to maintain vigour. Propagate: by dividing in the spring in cooler areas or the autumn in warmer areas.

How to Grow Helenium Plants on the Garden

Sneezeweed, Yellow Star and other Helenium Plants can be grown outside from seed by sowing them at the start of autumn, or the start of spring.

Once the seed is sown, give it a light covering of topsoil.

They should be grown in a sunny area of the garden, ideally with a rich soil of PH 5.5 to 7.

If you prefer you can start Helenium plants off indoors first. Sow them about 10 weeks before they are due to be transplanted into the garden, before the last frost of spring.

They should take around one to two weeks to germinate at a temperature of 21 degrees Centigrade (70°F).

Once ready the seedlings should be transplanted about 40 cm (16 inches) apart (small species of Helenium) or 75 cm apart (30 inches; large species of Helenium).

Caring for Sneezewort, Yellow Star, and other Helenium Plants

Once growing in the garden, yellow Star, Sneezewort and other Helenium members should be pinched back in the spring to delay flowering until the autumn.

Following flowering, deadhead the plants to encourage further growth.

At the end of the blooming season, cut the plants back to the ground.

It is best to divide every four years to maintain healthy growth; division can also be used to create more plants in the spring.

Common Questions

How many members does the Helenium genus have?

The Helenium genus includes approximately 40 species, offering a range of colors and shapes for gardeners.

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

Absolutely, many Helenium species are cherished for their vibrant late summer blooms, adding color to gardens when many other plants are fading.

Which Helenium species are most frequently grown by gardeners?

The most commonly grown species is Helenium autumnale, known as Sneezeweed for its history of being used in snuff.

Are members of the Helenium plant genus fragrant?

Most Helenium species are not particularly fragrant, but their vibrant colors more than compensate for this.

What is the perfect location to grow Helenium?

Helenium prefers full sun and moist but well-drained soil. It's a great choice for a sunny border or a wildlife garden.

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

Currently, Helenium is not considered invasive in the USA.

How do I remove Helenium plants from my garden?

Helenium plants can be removed by digging them up, ensuring all roots are removed to prevent regrowth.

Summary

The Helenium genus is a member of the Asteraceae family. Native to the Americas, they are admired for their daisy-like, vibrant blooms during summer and fall. Popular species include Helenium autumnale and Helenium bigelovii.

Helenium prefers full sun and rich, well-drained soil. These perennials need regular watering, especially during dry spells. To encourage bushier growth and more blooms, pinch back the stems in the early summer. Propagation is typically done by division in spring or fall.

I hope that you enjoyed this guide on how to grow Helenium plants. You may also enjoy my gardening guides on how to grow Freesia, Uvularia plant, and Trillium plants.