Plant potted coneflowers (Echinacea) in fall or spring; Clemson says fall is the best time. From seed, sow indoors 8 to 10 weeks before planting out (Johnny's), or sow outdoors in fall so winter chills the seed (Johnny's, Mississippi State). Give them full sun to part shade and well-drained soil, and don't bury the crown (Mississippi State). Plants from seed often take 2 years or more to reach full size and bloom well (Clemson, Wisconsin).
Coneflowers are native perennials of the central and eastern United States (NC State, Clemson). Purple coneflower (E. purpurea) is the most common; Clemson lists 2 to 3.5 feet tall, and NC State 3 to 4 feet. Other species include the narrow-leaf, pale and yellow coneflowers (Clemson, Wisconsin), and many hybrids come in orange, yellow, white and double forms. Hardiness depends on the species: Clemson gives zones 3 to 9 for the genus, NC State lists 3a to 8b for purple coneflower, and Penn State 3 to 9. Bloom runs from early summer into fall (NC State, Clemson).
When to plant coneflowers
| Timing | What the sources say |
|---|---|
| Fall (potted plants) | Clemson says fall is the best time to plant echinacea |
| Spring (potted plants and divisions) | Johnny's transplants in late spring or early summer; Mississippi State and Clemson divide clumps every 3 to 4 years in spring (Clemson also allows fall) |
| 8 to 10 weeks before planting out (seed indoors) | Johnny's sows indoors then; germination takes 10 to 15 days at 65 to 70°F (Johnny's) or 10 to 20 days (Clemson). Clemson says seedlings are ready to move 20 to 28 days after sowing |
| Spring, once soil reaches 65°F (seed outdoors) | Johnny's sows 3 to 4 seeds together, 1/8 in deep. Clemson allows outdoor sowing in spring or summer, up to 2 months before frost |
| Fall (seed outdoors, natural chilling) | Johnny's and Mississippi State allow a fall sowing outdoors, which gives the seed a cold, moist period over winter. Wisconsin uses fall sowing for yellow coneflower |
Our planting calendar counts back from your last frost: 8 to 10 weeks before it is the indoor seed window (Johnny's). Sources differ on chilling the seed. Penn State says the seed needs cold stratification, Mississippi State suggests 30 to 90 days of cool, moist conditions, and the USDA fact sheet says it isn't required but improves germination. Wisconsin chills yellow coneflower seed in moist sand in the refrigerator for 1 to 2 months. In our reading, a few weeks of chilling is cheap insurance, and a fall sowing outdoors does the same job (GardenPal reasoning).
How to plant coneflowers
| Coneflower | |
|---|---|
| Light | Full sun to part shade (Clemson, NC State, Mississippi State, Johnny's) |
| Soil | Well drained (Mississippi State, Johnny's); NC State and Penn State say it adapts to clay or rocky soil. The USDA fact sheet prefers pH 6.5 to 7.2 and says it won't tolerate waterlogging |
| Crown | Set at the same level as the surrounding soil, never deeper, to avoid crown rot; raised beds or berms help drainage (Mississippi State) |
| Spacing | 18 to 24 in (Johnny's); Clemson lists plants 20 to 28 in wide and says good spacing helps prevent disease |
| Seed depth | 1/8 in (Johnny's); 1/8 to 1/4 in (USDA). Clemson covers seed lightly because light can slow germination |
Watering, feeding and deadheading
- Water until established. Coneflowers are drought tolerant once settled (NC State, Clemson). Clemson avoids overhead watering.
- Feed lightly. Clemson says they are not heavy feeders; Mississippi State adds compost or a balanced slow-release fertilizer each spring.
- Mulch, but not on the crown. Mississippi State pulls mulch away from the crown so it doesn't stay wet.
- Deadhead or leave seed heads. Deadheading encourages more flowers (Mississippi State), but goldfinches eat the seeds, so Clemson and Penn State leave some heads for winter. Plants also self-sow (NC State, Clemson).
- Divide every 3 to 4 years to prevent crowding (Clemson, Mississippi State).
Coneflowers in containers
Mississippi State says large containers are a good way to improve drainage, using a commercial potting mix. Compact cultivars such as 'Kim's Knee High', 12 to 18 inches tall (Clemson), suit pots best.
Fall and winter
- Leave stems standing. NC State suggests cutting dead stems back to 12 to 24 inches for stem-nesting bees, and leaving seed heads for birds. Clemson removes old stems in fall, winter or early spring.
- Wet winters are the main risk. Mississippi State says coneflowers can be short-lived there because of crown rot in cool, damp winters.
- Salt: NC State lists salt tolerance, but Clemson says coneflowers struggle on the South Carolina coast because of poor salt tolerance.
Pests and problems
Aster yellows, spread by leafhoppers, causes green, tufted, distorted flowers; remove and destroy infected plants (Clemson) and don't compost them (Mississippi State). Clemson also lists stem rots, powdery mildew, anthracnose, aphids, Japanese beetles and eriophyid mites, and says rabbits can eat plants to the ground. Mississippi State adds spittlebugs. Sources differ on deer: NC State and Clemson call coneflowers deer resistant, while Penn State says they are not deer-resistant.
Coneflowers around the vegetable garden
Coneflowers are butterfly and pollinator plants (Clemson, NC State), so a clump near the vegetable garden can bring in visitors. Mississippi State pairs them with ornamental grasses, 'Autumn Joy' sedum, rudbeckias, Mexican bush sage and lamb's ear; Penn State suggests lavender, Russian sage and salvia; Wisconsin pairs yellow coneflower with bee balm and catmint. For more sunny-border plants, see when to plant liatris, when to plant lavender and flowers that attract beneficial insects.
Frequently asked questions
What is the best time to plant coneflowers?
Clemson says fall is best for planting echinacea. Spring planting works too; Johnny's transplants seedlings in late spring or early summer.
Do coneflower seeds need cold stratification?
Penn State says yes. The USDA fact sheet says it isn't required but improves germination, and Mississippi State suggests 30 to 90 days of cool, moist conditions or a fall sowing outdoors.
Will coneflowers bloom the first year from seed?
Often not much. Clemson says plants from seed can take 2 or more years to reach full size, and Wisconsin says yellow coneflower usually blooms in its second or third year.
Why are my coneflowers dying?
Usually wet soil. Mississippi State warns that a buried crown or wet winter soil causes crown rot. Aster yellows can also kill plants (Clemson).
Should I deadhead coneflowers?
Deadheading brings more flowers (Mississippi State), but leaving some seed heads feeds goldfinches in winter (Clemson, Penn State).
Are coneflowers deer resistant?
Sources disagree. NC State and Clemson say they are, while Penn State says they are not deer-resistant.
Enter your frost dates to time indoor coneflower sowing or a fall planting.
Open itSources
- Virginia Cooperative Extension, "Companion Planting in Gardening" (SPES-620P)
- University of Maryland Extension, "Vegetable Succession and Companion Planting"
- Oregon State University Extension, "Companion Planting"
- Penn State Extension, "Herbs Make Good Plant Partners and Companions"
- University of Minnesota Extension, "Planting the vegetable garden"
- USDA Plant Hardiness Zone Map
- NOAA NCEI U.S. Climate Normals (frost/freeze data)
- NC State Extension Gardener Plant Toolbox, "Echinacea purpurea"
- Clemson Cooperative Extension HGIC, "Echinacea (coneflower)"
- Mississippi State University Extension, "Purple coneflowers for the Mississippi gardener"
- Penn State Extension, "Purple coneflower"
- Johnny's Selected Seeds, "Echinacea: key growing information"
- USDA NRCS Plant Fact Sheet, "Eastern purple coneflower"
- University of Wisconsin-Madison Extension (Susan Mahr), "Yellow coneflower, Echinacea paradoxa"
Pairings are summarized in our own words from extension-service guidance. Research support for many companion effects is limited, so treat them as good habits, not guarantees.