How to Plant, Grow, and Care for Sneezeweed
Are you looking for a perennial plant that is native and brings plenty of color to the garden in summer and fall? Sneezeweed is a low-maintenance plant that can do just that! In this article, gardening expert Melissa Strauss tells all about sneezeweed, how to grow and care for it.
Sneezeweed, also known as Helenium or Helen’s Flower, is a delightful, adaptable, and attractive perennial plant. This warm-weather herbaceous plant blooms from late summer through the fall, making them an important food source for pollinators when fewer plants are in bloom. Pollinators are drawn to helenium-like magnets.
This plant is native to all parts of the United States except Alaska, which means it can grow in almost any garden! Here is everything you need to know about caring for this dazzling flower.
Sneezeweed Plant Overview
Plant Type Perennial
Species about 40
Native Area North America
Exposure Full sun
Soil Average to rich, moist
Soil pH 5.5-7.0
Hardiness Zones 3-9
Bloom Colors Warm Colors from Yellow to Red
Height up to 5’+
Season Late Summer, Fall
Pests Slugs, Spidermites
Diseases Powdery Mildew, Leaf Spot, Rust
The name Helenium comes from the story of the infamous Helen of Troy. Legend has it that where the tears of Helen fell on the ground, these flowers sprang up in their place. As Helen was best known for her enticing beauty, it’s not surprising that the flowers named for her are also quite pretty.
The nickname “sneezeweed” comes from the flowers’ ancient use as a form of snuff. When dried and ground into a powder, Helenium can be inhaled to induce sneezing. Sneezing was once thought to be a way to rid the body of evil spirits and alleviate cold symptoms, although we now know that isn’t true. Today, the plant is a popular ornamental.
Sneezeweed is an herbaceous perennial in the Aster or Daisy (Asteraceae) family. There are about 40 species of heavily flowering plants in the Helenium genus. The most common species is Helenium autumnale, named for its fall blooming habit.
The seeds, leaves, and flowers are toxic to humans and animals. The side effects of ingesting the plant include gastric and intestinal issues, which can be fatal in some cases. It also contains sesquiterpene lactones, which cause skin irritation, particularly to mucous membranes.
Helenium is best known for the abundance of flowers it produces. The plant is not unattractive otherwise, but its flower shows are something to behold. It is especially floriferous for a fall-blooming perennial.
The flowers are actually flower heads made up of small disk flowers in the center, flanked by an outer ring of ray flowers. Pollinators of all kinds love these flowers for their abundance of nectar.
The flower heads come in colors on the warm end of the spectrum. They can appear in various shades of red, orange, yellow, and copper, with many varieties containing two or more of these colors. These flowers are similar to those produced by Gaillardia or Indian blanket but typically have dark brown centers.
Sneezeweeds can be propagated in several ways. The most common is to propagate from seed. However, it can also be propagated by cuttings and division. The plants should be divided every few years, whether to propagate or otherwise. Thinning out plants will help increase air circulation, preventing diseases and pest infestation.
When clumps are divided to maintain the health of the parent plant, propagation is quite simple. New shoots and clumps can be dug up, cut from the central root system, and planted elsewhere.
The soil temperature needs to be reasonably warm to grow from seed. 70°F is ideal for germination, which takes place in 10-21 days. The seeds can be started in seed trays indoors in cooler climates. Lightly press the seeds into potting soil.
Do not cover, as these seeds need light to germinate. Keep the seeds consistently moist by misting the newly-planted seeds and laying a piece of cling film over the top of the soil to keep the moisture from evaporating. Carefully remove the film when you see the first signs of germination.
The best time to plant is in spring, so the plants have time to establish themselves before the late summer blooming season. Sneezeweeds do not have to be buried deeply. If planting bare root plants, dig a hole that is as deep and twice the width of the root. Place the root in the position you prefer and backfill lightly. The soil should be just even with the top of the roots.
How to Grow
Sneezeweed is an easy plant to grow and take care of. With such a wide native range, Helenium grows as a wildflower throughout the United States and much of Canada. These plants can withstand harsh weather conditions.
They’re cold-hardy as far north as zone 3. They are also heat tolerant all the way south to zone 9. Sneezeweed requires very little maintenance once established.
Sneezeweed comes back larger each year, so planting it in a small container will most certainly result in frequent repotting. If you want to grow your Helenium in a container, we recommend either a large pot or a raised bed that will contain its spread while giving your plants plenty of room to grow. A raised bed of sneezeweed can be a gorgeous sight when in bloom.
Full sun is best for sneezeweed to get the most blooms from your plant. If planted in the shade, Helenium will get quite leggy as it grows toward the light. Strive for 6 hours of sun, or more, per day. The morning sun is the best, as it is cooler than the afternoon sun.
If your plants get any shade, afternoon shade is best. The more sun these plants can get in the early part of the day, the more beautiful and floriferous your sneezeweed will be.
This is an excellent thing to remember when choosing a spot for your plants. In warmer climates, the concept of full sun can be different than in cooler climates.
If you’re growing Helenium in a warmer climate, ensure your plants have some shade from the afternoon sun. Plants should be placed in a location that gets as much sun as possible in cooler climates.
Sneezeweeds have moderate watering needs. While they are considered somewhat drought-tolerant once established, these plants prefer consistently moist soil. They will suffer if not watered during prolonged drought.
These plants will thrive best when given at least an inch of water per week. Water your Helenium whenever the soil is dry for the best results. Applying a layer of mulch around the bottom of the plant will help to retain some moisture in the soil.
Helenium plants prefer their soil to be somewhat acidic. A pH of 5.5-7.0 is ideal for these plants.
A moderately firm soil is preferable. Clay-heavy soil with organic matter mixed into it is ideal for these plants, but they will survive in most soil types. Consider adding worm castings to your native clay soil.
The exception is sandy soil. Because of their relatively high need for moisture, sandy soil is not a good option for these plants. Planting Helenium in soil that drains well but that still retains moisture is best. These plants do well in moist soil but don’t enjoy boggy conditions.
Climate and Temperature
Sneezeweed grows in a very large native range. From central Canada to Florida and Texas, Helenium is widely adaptable. These plants are warm-weather bloomers, but their roots are hardy as far north as Zone 3, so they have excellent cold tolerance in their dormant season.
As an herbaceous perennial, the above-ground plant parts will die back in cold winters. Don’t worry; they should regenerate in spring!
Humidity and heat are not big issues. These plants can tolerate hot, humid summers as long as they are given enough moisture. In areas where the humidity level is particularly high consistently, watch out for fungal disease, and don’t allow your sneezeweed to become overly crowded. Humid climates tend to make plants more susceptible to fungal disease.
Heleniums are not heavy-feeding plants. They won’t need regular fertilizing as long as they are planted in fairly rich soil. Too much fertilizer or nitrogen-rich soil will mean more foliar growth and fewer flowers, so avoid fertilizing throughout their growing season.
Maintenance and Care
Aside from that single yearly fertilizing, Heleniums are very low maintenance. In late spring, once the plants have had some time to grow, pinching back the new growth will result in a later bloom but will produce sturdier plants with more branches, thus more flowers.
After your sneezeweed has bloomed, cut back all flower stems down to the foliage. Deadheading throughout the flowering season will also encourage more flowers and help the plant direct energy toward new growth.
Every few years (3-5), you must thin the patch. These perennials will crowd each other after a while, making them more susceptible to disease. Plants will also lose their vigor if allowed to multiply too freely. Separating plants every so often will keep them strong.
There are more than 40 species of Helenium and many hybrid variations from several countries. The plant’s excellent cold and heat tolerance makes it quite popular as an ornamental pollinator plant. Here are some of my favorite varieties with the most unique and beautiful blooms.
|botanical name Helenium autumnale ‘El Dorado’|
|bloom colors Yellow and Red|
|height up to 3’|
|hardiness zones 4-8|
‘El Dorado’ lives up to its name with masses of golden flowers during a long blooming season from summer through fall. This compact variety reaches only about 3’ tall, but this small size has benefits. ‘El Dorado’ has sturdy stems that show resiliency to environmental factors like wind and rain.
The flowers appear from July through to October and have deep brown centers speckled with tiny yellow stamens around the edge. The larger petals are bright yellow and occasionally have small red splashes.
|botanical name Helenium ‘Hot Lava’|
|bloom colors Red|
|hardiness zones 4-9|
This hybrid was created in the Netherlands to grow compactly and produce especially flashy flowers. These pretty blooms appear as yellow with some red streaking. As the flowers mature, their color intensifies to a deep crimson red before fading to a softer shade of orange.
The color-changing nature of these flowers makes this variety extra popular. They show up en masse from early summer through to the fall months. They also make excellent cut flowers with sturdy stems, upward-facing blooms, and a long vase life.
|botanical name Helenium ‘Helbro’ Mardi Gras|
|bloom colors Yellow, Orange, and Red|
|height 3’ – 4’|
|hardiness zones 3-8|
You may have guessed by the name that this plant is a real garden party. ‘Mardi Gras’ is a slightly taller variety, reaching 4’ tall when mature. Pinching this variety in late spring will lead to rich, dense foliage and plenty of flowers. The stems are nice and strong in this variety, so the flowers are great for cutting.
The flowers appear during midsummer in a great, colorful show. The center of the blooms is reddish brown. The base color of the blooms is bright yellow splashed with brilliant red and orange, making for a very colorful and interesting plant.
|botanical name Helenium ‘Potter’s Wheel’|
|bloom colors Red and Yellow|
|height 3’ – 4’|
|hardiness zones 3-8|
‘Potter’s Wheel’ is a Dutch hybrid Helenium variety. This cultivar flowers so heavily in late summer that it often needs support to hold up its stems. The flowers bloom in clusters at the end of branches, making this one of the most floriferous varieties.
The blooms have a chocolate brown center which gradually turns yellow as the flowers age. The larger circle of petals is a deep, velvety red with a thin yellow halo around the very outer edge of the flower. The flowers are set off nicely against attractive green foliage.
‘Ring of Fire’
|botanical name Helenium ‘Ring of Fire’|
|bloom colors Yellow and Red|
|height 4’ – 5’|
|hardiness zones 5-9|
Another delightful hybrid, ‘Ring of Fire,’ is an award winner for good reason. This taller variety reaches up to 5’ tall, making it a great midground flower in the garden. Plant this variety, and you will see many native bees and butterflies visiting the garden.
‘Ring of Fire’ blooms in late summer. The flowers are a reddish brown color, with rings of yellow toward the center and around the outer edges. Sometimes the flowers have a splashier appearance, with the yellow portions woven throughout the darker background shade.
|botanical name Helenium ‘Short n’Sassy’|
|bloom colors Yellow and Orange|
|hardiness zones 4-8|
‘Short n’Sassy’ has some great characteristics that make it wonderful for borders and foreground planting. This cultivar was hybridized to have a dwarf growing habit, so it only reaches about 18” tall at maturity. It was also bred to have an earlier and longer blooming habit, so it will begin blooming mid-summer and continue to show off until September.
This variety has smaller flowers, around 1.5” rather than a more standard 2”. Not a huge difference, but noteworthy as it was bred to be smaller. Bright golden yellow and orange flowers have downturned petals that surround a chocolate brown central cone.
Pests and Diseases
Sneezeweeds are surprisingly pest-deterrent and deer-resistant. Few typical garden pests spend much time seeking out these plants. Instead, they are incredibly popular with various pollinating and beneficial insects. They are vulnerable to a few diseases, but for the most part, Helenium is notorious for being easy to grow and sturdy.
Slugs and snails can be an issue for young plants, although, once mature, Helenium is not much of a target for these slimy garden snackers. There are many ways to deter slugs and snails from eating your plants.
Diatomaceous earth can deter slugs and snails until it gets wet. They are also not partial to bark mulches, as the bark often has fine slivers that repel them.
A wide copper strip around the exterior of your container or garden bed can also keep them at bay. Once your plants are mature, the slugs and snails are less concerning of an issue.
Spider mites are a potential problem for Helenium. However, they are unlikely to do great damage to mature plants. They are best detected by identifying the thin, weblike structures they build beneath plant leaves. These insects feed on the sweet sap of plants, leading to shriveled and stunted growth.
Neem oil is an effective treatment for spider mites, as are insecticidal soaps and horticultural oils. However, with sneezeweed being so popular among pollinating insects, spraying them with insecticides is not ideal. Use neem oil in the evening after pollinators have left.
Some varieties, such as ‘Sombrero,’ have been bred for better resistance to powdery mildew, but this is the most common issue for other cultivars.
Powdery mildew is a fungal disease usually resulting from overcrowding in the garden and occasionally from watering in the evening, as the damp leaves and cooler temperatures create a perfect condition for fungal spores to take hold.
This fungal disease is easy to detect. It causes a powdery white appearance to appear on foliage and can permanently discolor leaves. It is rarely fatal to the plant but can lead to less robust plants that don’t flower well. Thin out plants that become crowded to improve air circulation and prevent infections.
Rust is another fungal disease that spreads via fungal spores, often carried by water. Water splashing onto a leaf surface and pooling there can spread these spores and infect the plant. Watering plants at the base rather than overhead can help to reduce the risk of fungal diseases on the foliage of your plants.
Rust diseases create red, blister-like masses on the underside of affected leaves, releasing a red powdery substance containing spores. On the upper surface of the masses, it will be reddish-brown in color, similar to the rust from which it takes its name. It doesn’t look very nice, and additionally, it damages the health of the plant as a whole, making it more vulnerable to other diseases and pests.
Dusting affected plants with sulfur powder once a week until the disease is no longer active is an effective treatment for rust, provided that the leaves stay dry; if they do not, the sulfur powder will be washed off the leaves and the treatment will be ineffective.
Leaf spot can refer to several different diseases commonly affecting ornamental and edible plants and trees. The cause can be bacterial or fungal, and insect damage may be mistaken for a leaf spot disease. The most common symptom, of course, is spots on the leaves. These can be black, brown, or white and of different shapes and sizes, depending on the cause.
Plants in the Asteraceae family are most commonly affected by Septoria, Alternaria, and Cercospora. All three of these are fungal and can be dealt with similarly. All affected foliage should be removed, and the rest of the plant should be treated with a fungicide. Avoid allowing water to pool or sit on the leaves until things are under control.
Sneezeweed, or Helenium, is a versatile, hardy, low-maintenance flowering perennial. It is easy to grow and native to most of the North American continent. Very few pests, including deer and rodents, are attracted to this plant, and pollinators will be grateful for the late-season nectar and pollen that these plants will provide.
Adding some of this pretty, flowering plant to your garden will bring a huge pop of late summer and fall gardens and come back year after year with more of their cheery blooms!