How to Grow and Care for Coneflowers

Introduction

Coneflower is a native North American perennial sporting daisylike flowers with raised centers. The flower, plant, and root of some types are used in herbal remedies.

About coneflowers

Widely renowned as a medicinal plant, coneflowers are a long-flowering perennial for borders, wildflower meadows, and prairie gardens. Blooming midsummer to fall, the plants are relatively drought-tolerant and rarely bothered by pests. The flowers are a magnet for butterflies, and the seeds in the dried flower heads attract songbirds. Flower colors include rose, purple, pink, and white, plus a new orange variety. Plants grow 2 to 4 feet tall, depending on variety.

Special features of coneflowers

1. Easy care/low maintenance

2. Multiplies readily
   

3. Good for cut flowers
   

4. Attracts butterflies
   

5. Deer resistant
   

6. Tolerates dry soil
   

Choosing a Site to Grow Coneflowers

Select a site with full sun to light shade and well-drained soil.

Recommended Varieties

Purple coneflower (E. purpurea) is the most widely available species. Recommended cultivars include Alba (creamy white with coppery tones), Bright Star (red to rose petals, flatter form), Magnus (broad pink petals with brown cone), White Lustre (reflexed white petals with orange cone), and White Swan (white flowers with deep orange cone, comes true from seed).

Black Sampson (E. angustifolia) grows only 10 to 24 inches tall, producing light purple to rose pink flowers 2.5 to 3 inches in diameter. Pale Purple Coneflower (E. pallida) grows 3 to 3.5 feet tall with distinctive 3- to 6-inch flowers featuring reflexed petals. Most coneflowers are hardy to zone 3.

Planting Instructions for Coneflowers

Plant in spring, spacing plants 1 to 3 feet apart, depending on the variety. Prepare the garden bed by using a garden fork or tiller to loosen the soil to a depth of 12 to 15 inches, then mix in a 2- to 4-inch layer of compost. Dig a hole twice the diameter of the pot the plant is in. Carefully remove the plant from its container and place it in the hole so the top of the root ball is level with the soil surface. Carefully fill in around the root ball and firm the soil gently. Water thoroughly.

Plant coneflower in a sunny location that has well-drained, fertile soil. Most can thrive on available rainfall once established, and plenty of sun and heat won't bother them. The long-blooming, colorful flowers are at home in sunny borders, herb gardens, cottage gardens, prairie gardens, or wild gardens.

Propagate by seed, or dig and divide the main rootstalk in spring or fall. Root division is an alternative for all species, but it is most successful with E. purpurea. The best time to divide roots is in early autumn or spring. Cut through the crown of the coneflower clump with a sharp spade. Separate two to three young roots and shoots from the main plant every 4 to 5 years.

Grow coneflower plants from seed following a dormancy-breaking period. Seeds germinate best between 70° and 75°F and, for E. purpurea, after dry prechilling (1 to 3 months at 40°F). Sow seeds indoors 6 to 8 weeks before the last frost date in your area; or sow on the surface of a sandy soil mix in an open cold frame in early spring. (See individual species descriptions for exceptions.) Seeds normally germinate within 10 to 20 days. Transplant seedlings outside after all danger of frost has passed. Coneflower self-sows readily but not aggressively.

In short-season regions, coneflowers may need more than one growing season to produce flowers unless seeds are started early indoors.

In northern areas (zones 3, 4, and 5), plants need to develop roots fast. Pinch off flower buds that develop the first year from seed. The plant will divert its energy into root development. In mild-winter areas, coneflower may grow and flower the first year from seeds sown in the garden.

Ongoing Care for Coneflowers

Apply a thin layer of compost each spring, followed by a 2-inch layer of mulch to retain moisture and control weeds. Water plants during the summer if rainfall is less than 1 inch per week. Deadhead spent flowers to extend flower period, but leave late-season flowers on the plants to mature; the seedheads will attract birds. Divide plants every 3 to 4 years as new growth begins in the spring, lifting plants and dividing them into clumps.

To extend the flowering period of mature plants, cut off faded flower heads. However, toward season's end, you may want to leave some to dry out on the stems: They make attractive forms in winter, and their seeds attract many birds, especially finches.

Pests and Problems for Coneflowers

Depending upon where you live, you may need to protect young plants from rabbits and groundhogs that find new shoots appetizing. The only other pests are leaf spot fungus and Japanese beetles, but neither is likely to kill the plant, so I recommend no treatment other than picking off the beetles. Caterpillars are known to defoliate coneflower plants. If you prefer the plants to the potential butterflies, use Bt (Bacillus thuringiensis) to control caterpillar infestation. Daily caterpillar picking is the butterfly-friendly alternative.

Medicinal Properties and Use for Echinacea (Coneflower)

Native Americans considered coneflower an important medicinal plant. They applied crushed root pieces directly to venomous bites and stings, and they chewed on dried root to treat a variety of ailments. Modern herbalists agree that coneflower root is one of the best herbal remedies available to prevent, and reduce the severity of, colds and flu.

Both roots and aboveground parts of E. angustifolia and E. purpurea are the sources of most of the modern echinacea remedies, but the dried roots are used in homemade preparations. Powdered roots and tinctures are sold in health-food stores and some supermarkets.

Allow seed-started plants to grow for 3 to 4 years before harvesting roots; divided plants need two years. Dig them in the autumn after flowering is finished, and cut washed and dried roots that are thicker than 1/2-inch into sections to speed drying. Allow the roots to dry in a warm but shaded place. Replant the crown with smaller roots to continue your supply.

Prepare roots in either of these ways: Grind dried root pieces into a powder. Mix 4 tablespoons of powdered root per quart of water; cover and simmer over low heat for 20 minutes, then strain. Drink the solution hot or cool, 1 to 2 cups per day. The tea cannot be stored because it becomes unstable, which is why most herbalists prepare it in an alcohol tincture.

Make a tincture by covering washed, chopped, and dried root with 1 to 2 inches of 100-proof vodka in a clean glass jar that has an enamel cap. Allow it to steep at room temperature for two weeks, shaking the container daily. Proper dosage is an individual matter, and you should consult with a naturopathic physician or qualified herbalist before using any herb. Echinacea tincture is effective in very small amounts. Generally, half to one full eyedropper (30 to 60 drops) a day in water, juice, or tea is about right.

Frequently Asked Questions about Coneflowers

I planted new coneflowers, amended the hole generously, and now the leaf edges are brown and curling. What is wrong?

The amendments are the most likely reason, which is a hard thing to hear after a lot of digging. Coneflowers are prairie plants. They evolved on lean, fast draining ground, they carry a deep taproot on the straight species, and they are adapted to soils that dry out between rains. Average to poor soil with good drainage suits them better than anything you can improve it with.

The specific problem with a large hole dug in clay and filled with compost, manure and other amendments is that you have built a bathtub. Water moves easily through the loose material you added, reaches the clay wall of the hole, and stops, because water does not move readily from a fine textured soil into a coarse one or the reverse. The result is a sump that holds water around the crown and roots long after the surrounding ground has drained. The plant looks good for a few weeks on the stored nutrients, then the roots begin to suffocate, and the first visible symptom is scorched, curling leaf margins, which is exactly what a plant that cannot take up water looks like whether the cause is drought or drowning.

Go and check before you do anything else. Dig at the edge of the planting hole, down toward the bottom, a day or two after a watering. If the material there is wet and heavy while the surrounding ground is merely damp, you have your answer. Look at the roots at the same time: healthy coneflower roots are firm and creamy white inside, while roots that are brown, black or rusty, soft or slimy have already rotted.

Watering on a schedule and then cutting back is the natural thing to do and rarely the right one. Stop watering by the calendar and start checking by feel. Push a finger, or better a wooden dowel, several inches into the soil near the plant, and if it comes out damp, do not water. Established coneflowers tolerate real drought; newly planted ones need enough water to establish but not a saturated root zone. The direction of the error changes with the season, though. In their first summer on a hot west facing slope they do need regular water while the roots grow out, which is different from the drought tolerance they will have in their second year.

If the hole is holding water, the fix is to lift them and replant higher. On a slope, a terraced pocket or a low berm works well, and setting the crown an inch or so proud of the surrounding grade keeps water off it. Do not backfill with amended soil this time. Use the native soil you took out, break up the sides and bottom of the hole so roots can penetrate, and if you want to improve the ground generally, spread organic matter over the surface of the whole bed and let it work down rather than concentrating it in a hole. Mulch an inch or two deep, kept off the crown. Coneflowers resent disturbance once established, so if you are going to move them, fall or the following spring is the moment.

While you are there, ignore the bone meal for future plantings unless a soil test says you need phosphorus. Most established garden soils have plenty, coneflowers are not heavy feeders, and rich soil produces the specific problem these plants are known for: tall, soft, floppy growth that falls over in the first storm. A lean site gives you shorter, stiffer stems that stand up on their own.

As for the plants themselves, cut off the spent flower stems and remove leaves that have clearly died, but leave the rest of the foliage alone until frost. Green leaves are still feeding the root system, and that is what the plant will restart from. Coneflowers are genuinely tough, and a plant that is only drowning rather than rotted usually comes back the next spring with better stems than it had this year.

My coneflowers looked perfect and then the whole plant wilted and died within a day. What causes that?

Sudden total collapse, with no gradual yellowing and no insects to be found, is a root or crown problem almost every time. The top of the plant is fine right up to the moment it can no longer be supplied with water, and then it goes all at once. Dig the plant up rather than guessing. It takes five minutes and it tells you what happened.

Root and crown rot is the usual finding, and poor drainage is the usual cause. Healthy roots are firm and white to cream inside when you cut one. Rotted roots are dark brown, black or rust colored, often soft, sometimes slimy, and they smell sour. Look particularly at the crown, the point where the stems meet the roots, because on coneflowers rot right at soil level kills a plant faster than anything happening further down. If some roots are still sound, you can cut away the dead material and replant the healthy remainder in a better drained spot, and it is worth trying. If the crown itself has gone soft, the plant will not recover.

The conditions that produce it are the ones described above: heavy soil, an amended planting hole that acts as a sump, watering in the evening so the crown stays wet overnight, mulch piled against the stems, and plants set too deep. The crown of a coneflower should sit at grade, never below it.

Three other explanations are worth checking if the roots turn out to be healthy. Voles eat coneflower roots and crowns, and the damage is invisible until the plant collapses; the tell is that the plant lifts out of the ground with almost no resistance and the roots have been chewed off cleanly rather than rotted, with quarter sized holes and surface runs under the mulch. Southern blight, which appears in hot humid regions, produces a distinctive white fungal mat at the base of the stem with small tan or reddish spheres in it, about the size of mustard seed; if you find that, remove the plant with the soil immediately around it and do not compost it. And stem borers tunnel down the stem of coneflowers in some areas, so split a wilted stem lengthwise and look for a hollowed channel and frass.

None of these is worth treating with a spray. The response in each case is sanitation and site correction: remove what has died, improve drainage before replanting, water the ground rather than the plant, keep mulch off the crown, and give the plants enough space that air moves through the planting. Coneflowers set closely in a solid block in humid weather have far more of this trouble than the same plants at honest spacing.

My coneflower foliage went black last summer. How do I prevent it?

Foliage that blackens and spreads through a planting over the course of a season is usually bacterial leaf spot rather than the fungal leaf spot coneflowers more often shrug off. Both Pseudomonas and Xanthomonas species affect echinacea. Neither can be cured once a leaf is infected, so the whole approach is sanitation and drier foliage, and it is worth doing because the plants themselves are rarely killed.

Pick off and dispose of infected leaves and stems as you see them rather than composting them, and cut the plants down and clear the debris thoroughly at the end of the season so there is less for the bacteria to overwinter in. Water at the base of the plant instead of overhead, and if the foliage does get wet, water in the morning so it dries quickly rather than staying damp overnight.

Then give the planting sun and room. A crowded clump holds moisture around its leaves for hours after rain, which is exactly the condition these bacteria need, so dividing an overgrown clump and thinning the perennials pressing in around it does more good than any treatment. If you are setting out new plants, choose a fresh spot rather than replanting into ground where the disease has been active. Managed this way, a planting usually comes through the following season clean.

My coneflowers have healthy cones but no petals. Is a pest eating them?

Maybe, but the more likely answer in most seasons is that they simply have not opened yet, and this is a case where waiting a week costs you nothing and spraying costs you something.

Coneflowers open from the center out, and the central cone forms and colors up first. The ray florets, the drooping petal like parts, unfurl afterward, one ring at a time. In a dry season, or during a hot spell, the whole sequence slows down noticeably and you can have cones standing bare for a week or more before the petals appear. If you never saw petals in the first place, patience is the treatment. Water the plants deeply once during a dry spell and they usually finish the job.

If you watched petals emerge and then disappear, something is eating them, and the usual suspects are chewing insects. Grasshoppers are the most likely in a dry summer and they take ragged bites out of ray florets. Various beetles feed on the flowers too, including the small metallic ones that work in groups. Earwigs chew petals at night and hide in the flower head by day, so look at dusk or shake a flower over a light colored surface. Slugs will do it in a wet season and leave slime trails on the stems. Sunflower head moth caterpillars are worth knowing about because they are common on coneflowers and often blamed on something else: they feed inside the cone, and the sign is webbing, frass and a chewed, hollowed center.

Two things that are not insects should also be ruled out. Aster yellows is a disease spread by leafhoppers and is unmistakable once you have seen it: flowers come out green and deformed, with tufts of small leafy growths sprouting out of the cone and ray florets that are stunted, twisted or absent. There is no cure. Dig affected plants out, bag them, and do not compost them, because leafhoppers move the organism from an infected plant to healthy ones. And deer and rabbits browse flower buds and open flowers cleanly, taking the whole top rather than nibbling petal edges, so if flowers vanish overnight at a consistent height from the ground, that is what is happening.

For genuine insect damage on an ornamental, the honest answer is that most of it does not need treating. The flowers are still there, the plant is not harmed, the damage stops when the pest generation passes, and coneflowers are one of the best pollinator plants in a summer garden. Spraying them is directly at odds with the reason most people grow them. Hand picking in the evening, floating row cover over young plants while a grasshopper flight passes, keeping the surrounding area free of tall dry weeds where grasshoppers breed, and simply tolerating some chewing are all better answers. If damage is severe enough that you decide to intervene, identify the insect first, take it to your county Cooperative Extension office if you are unsure, and use only a product whose current label names both the plant and that pest. Never apply anything to open flowers where bees are working, and if you must treat, do it in the evening after foraging has stopped.

Should I pinch the first flower buds off young coneflowers to make them bushier?

You can, but on coneflowers it will not do what you are hoping. Pinching works well on many annuals and on plants that branch readily from leaf axils. Coneflowers do not respond that way. They are naturally upright and rather gaunt in their first year, and pinching the top out mostly delays flowering without producing the fuller shape you want.

What actually fills them out is time. A first year coneflower builds its crown through the season and into the next, and a plant that looked like three thin stalks in June is a dense clump with a dozen or more stems by its second or third summer. That thickening comes from the base, not from branching at the top.

Two things do help in the meantime. Deadhead through the season: cutting a finished flower back to the next bud or leaf junction encourages the plant to push side shoots and extends the bloom period substantially, often from midsummer into fall. That is the pruning that pays on this plant. And plant in groups at close spacing so the plants support each other and read as a drift rather than as individual stems. Eighteen inches apart is generous for most garden cultivars and works well; you can go tighter for effect and thin later. Coneflowers divide and move easily in spring or fall, so a spacing decision now is not permanent.

Two other points about legginess. Light matters more than pruning: a coneflower in anything less than full sun stretches toward it and leans, and no amount of pinching corrects that. So does soil richness, as described above, because a well fed plant grows tall and soft. If you want stiff stems that stand without staking, give them sun and lean ground.

If you would rather not fight the habit at all, plant breeding has moved a long way on this point, and there are now many compact cultivars bred specifically to branch low and stay under two feet. One caution is worth knowing: some of the heavily bred double and unusually colored cultivars are less vigorous and shorter lived than the straight species and the older selections, and they are much less useful to pollinators because the doubled flowers hold little accessible nectar. If longevity and bees matter to you, the simple purple coneflower and its long established selections are still the most reliable plants in the group.

How do I get my coneflowers ready for winter?

Less than you might think, and the best thing you can do is leave them standing.

Do not cut them back while the foliage is still green. Leaves that are still working are still sending food down to the root system, and that reserve is what the plant restarts from in spring. Wait until frost has killed the top growth and the foliage has withered.

Then consider not cutting them at all until spring. The seed heads are one of the best winter food sources in the garden for goldfinches and other small birds, the standing stems catch snow and look good through the dead months, and the hollow stems and leaf litter shelter overwintering native bees and beneficial insects. Cutting everything to the ground in fall and raking the bed clean is tidy, and it removes all of that. The one situation where fall cleanup is genuinely better is where the plants had a disease problem during the season, because removing the infected material reduces what carries over. If you do cut in fall, take the stems down to about three inches once they have withered, and put diseased material in household waste rather than the compost pile.

Mulch is optional for an established plant in zone 4 or 5. Coneflowers are hardy well beyond that, and the plants do not need protecting so much as they need not to be heaved out of the ground by soil that repeatedly freezes and thaws. If you mulch, wait until the ground has actually frozen and then use something light and airy, such as evergreen boughs, straw or shredded leaves, a few inches deep. Applying heavy wet mulch before the ground freezes does the opposite of what you want: it keeps the crown warm and damp and invites the crown rot described above. Pull it back in early spring as growth starts. First year plants set out late in the season are the exception and are worth mulching, because their roots have not gone deep enough to resist heaving.

Do not fertilize in fall, and do not water once the plants are dormant unless you are in a dry winter climate where the ground never freezes.

When should I start coneflower seed, and does it need chilling?

Count back about ten to twelve weeks from the date you intend to set plants out, which for a middle of May planting means starting in late February or early March. If you have strong light and space to grow them on well, twelve to fourteen weeks gives you a bigger plant; if your light is marginal, ten weeks and a smaller, sturdier transplant is the better bet. Overgrown, stretched seedlings set out into wind and sun do worse than small compact ones, so if the weather turns against you it is better to hold the plants back than to rush them out.

The important step is the one most seed packets mention only briefly, and the usual advice often gets its timing backwards. Purple coneflower germinates far more reliably after a period of cold and moist conditions, which is what the seed would get lying on the prairie over winter, and that chill happens before you sow rather than after you sow and wait to see if anything comes up. Mix the seed with barely damp vermiculite, sand or a little seed compost, seal it in a labeled plastic bag or lidded container, and put it in the refrigerator, not the freezer, at around 40 degrees for four to six weeks. Then sow it. Fresh Echinacea purpurea seed often germinates perfectly well at ordinary room temperature with no chilling at all, which is why you will read that stratification is unnecessary. Both work; stratified seed simply comes up faster and much more evenly.

Sow into a moist seed starting mix, barely covering the seed since light helps germination, and keep the container at ordinary room temperature, around 65 to 70 degrees. Seedlings usually appear within one to three weeks. Bottom heat is not needed and can work against you. Once they are up, strong light is critical: a bright window is usually not enough by itself and produces long floppy seedlings, so use a fluorescent or LED plant light held a few inches above the leaves for fourteen to sixteen hours a day. Pot on into individual pots once the first true leaves are well developed.

An easier route, if you have the patience for a season's delay, is to sow outdoors. Scatter the seed on a prepared bed in late fall or early winter and let the winter do the chilling for you, or sow in a labeled pot of compost left outside over winter in a sheltered spot. This is how the plant does it in the wild, and germination is often better than anything achieved indoors.

Harden the plants off over ten days to two weeks before planting out, moving them into progressively more sun and wind and leaving them out overnight only once frost has passed. Set them out on the small side rather than large and stressed. Many gardeners grow first year perennials in a nursery row where they can be watched and watered easily, and move them into their final positions in fall or the following spring at a decent size.

Expect flowers in the second year. Some seed grown coneflowers will give you a modest showing in their first summer, particularly if started early, but the real display comes the year after. One last thing to know if you are collecting seed from your own plants: named cultivars, especially the modern colored ones, do not come true from seed, and the seedlings usually revert toward ordinary purple. That is not a failure, and the plants are frequently tougher than their parents.

The cleome I sowed at the same time did not come up either. Why?

This pairing comes up often enough to be worth answering here, because the two failures have different causes and both are easy to fix.

Cleome seeds must be sown on the surface or barely pressed into the mix. They need light to germinate, so if you covered them to any sowing depth, you buried them, and no amount of warmth will fix buried seed. Resow on top of the soil or seed starting mix, in a bright location where they stay evenly moist but are not covered. Cleome also responds to warmth and to a temperature swing: aim for a daytime high around 80 degrees and let it drop about ten degrees at night. A heat mat running around the clock at a constant temperature often fails where a windowsill with a day and night swing succeeds. An old or stubborn batch germinates better after a cold moist chill of a week or two, mixed with barely damp sand or vermiculite in a labeled bag and refrigerated around 40 degrees before sowing. Once up, cleome germinates readily and grows fast.

Garden cleome is Cleome hassleriana, now often placed in Tarenaya, and it is the tall spider flower. It self sows with real enthusiasm and will return year after year uninvited, which is worth knowing before you plant it, though some modern selections are sterile and set no seed at all. Its stems carry small spines and the foliage has a strong, distinctive odor, so wear gloves when handling, pulling or deadheading it.

Can I grow purple coneflower in south Florida?

Realistically, not as a perennial. You can have it in the garden, but not as a plant that comes back year after year the way it does elsewhere.

The explanation usually given is hardiness zones: Echinacea purpurea is generally listed for something like zones 3 to 8, sometimes 9, and south Florida sits beyond that. But the zone map only describes winter cold, and cold is not what is killing it. What defeats coneflower there is the other half of the year. Hot, wet summers are the real obstacle. Coneflower comes from prairie and open woodland, where it stands in soil that drains fast, and its crown is intolerant of sitting warm and saturated. A subtropical summer delivers exactly the opposite: heavy rain over ground that stays wet, soil temperatures that never drop, and humidity that keeps foliage damp for long stretches. The crown rots, and where it does not rot outright, foliar diseases build up on the leaves and grind the plant down. Nights that stay warm add to it, because a plant that cannot cool down at night is respiring away reserves it never gets to bank. The pattern people report is consistent: a plant put in during the cool season looks good, flowers, then thins out and disappears through its first summer, or limps through one and is gone in the second.

It does work as a cool season annual. Set plants out in fall, roughly October into November once the worst of the heat has broken, and grow them through the mild dry season. They will flower from late winter into spring, which is the best stretch of the year in that climate anyway, and deadheading keeps them producing. When real heat and the summer rains arrive, they finish. Pull them and plant something else, in the same way a northern gardener treats pansies.

If you want to give one the best chance of surviving longer, the whole strategy is keeping the crown dry: plant in a raised bed or a container rather than in flat ground, use a mix that drains sharply, give morning sun with some shelter from the worst afternoon heat, and keep mulch pulled back from the crown rather than heaped against it, since mulch on the crown is what turns a wet week into rot. Even done well, expect it to be short lived.

For something that genuinely persists through subtropical summers, ask locally and ask before you buy. Plant performance in south Florida varies sharply over short distances, so a recommendation that suits one part of the state fails in another. Your county extension service and your regional native plant society both maintain lists and will know what is thriving in gardens near you this year. If you want the coneflower effect specifically, a daisy shaped flower on an upright stem for sun, describe it in those terms and let them name the plants that deliver it in your conditions. Check any plant you are considering against your state and regional invasive plant lists before you buy it. Florida has an unusually serious invasive plant problem, several widely sold ornamentals have escaped into natural areas there, and the situation changes as new species are listed. Your extension office can point you at the current lists.

Mail order seed companies and perennial nurseries carry Echinacea purpurea as a matter of course, and started indoors in late summer, plants are ready to set out for the cool season. For plants, garden centers that buy for the local climate are worth trying first, and if they do not stock it, that itself tells you something about how it performs there. For anything marginal, extension service plant clinics, master gardener programs and native plant society sales are the most useful sources of all, because the people running them are growing in your conditions and will tell you plainly which cultivars have held up locally.