Echinacea Purpurea – How To Grow Purple Coneflower
September 16, 2018
Purple Coneflower/Echinacea Purpurea – How To Grow and Care
Echinacea purpurea Facts / General Description
Purple Coneflower, (Echinacea Purpurea) one of the most popular flower for landscapes and backyard micro-prairies, for good reason. This native perennial has a long bloom time and is very showy, also being very tall (3-5’, 1-1.5 m). I’ve have around 10-15 of various varieties in my garden at any one time. The roots of Echinacea typically go to around 5’ deep (1.5 m), making it very drought tolerant. This plant can thrive in any type of soil, even clay. But, it probably won’t survive if it is semi-wetland, or just a general moist area that doesn’t drain. In fact, this plant is so adapted to clay it is almost unbelievable. Nearly every picture of Echinacea you will see in this article was grown in horrible, tough, hard clay soil. I would add some good compost in the plants immediate area when transplanting, but that is all.
Echinacea will bloom later than its cousin, Pale Purple Coneflower (Echinacea Pallida). Having both plants in the garden can help give a longer bloom period. And that means, more color, more butterflies, and more bees!
It can do quite well with other companion plants, such as Heliopsis (False Sunflower), Bee Balm, Rudbeckia, Liatris, and many others. You just need to ensure that the plants are spaced accordingly. Mixing different species of native plants can really help your overall garden ecosystem, have a longer period of color, and give you more pollinators/birds to view as well.
Do Coneflowers Spread?
No, Coneflowers don’t send out runner roots or spread by rhizomes. The plant can grow to about 3′ diameter, however they won’t expand beyond that. Once a plant gets to be about 3′ in diameter, you should consider dividing it in the early Spring when it emerges from dormancy.
How to grow Purple Coneflower from seed
This plant is readily available from most garden centers, but the most economical way to grow it is from seed. It is available as seed packets, from most garden centers or from these websites Purple Coneflower seeds . Also, scroll down to see a ‘how-to’ video on planting seeds.
You can sow this seed at any time, although I wouldn’t start any seed beyond July 1st for USDA garden zone 6 and lower. This is because I want to ensure that the plant will have enough time to establish itself before dormancy sets in late September/October. Stratification is not required to germinate, although it will increase the germination rate. I generally use 3-5 seeds per pot/cell, and often find myself having to thin the cells whether they are stratified or not.
How to transplant Echinacea into the garden
Transplant small seedlings to larger pots once they begin to fill out their pots. I generally recommend something that is 4” square or diameter at a minimum. Let the seedling grow for another month or so before transplanting out to the garden. An extra step that is always good practice when planting any flower is to mix some compost into the soil when transplanting to the garden. I generally add about 1-2 pints (0.5 L), and dig the hole twice as wide as the plant, and twice as deep. This is to make growing roots as easy as possible for the young plant. However, this plant can thrive in clay soil, so this isn’t 100% necessary. It is just good practice to add compost, as it will lighten the soil making root production easier, as well as being a natural slow-release fertilizer. One more trick that is awesome is to pour some water into the whole, but don’t add the plant until it has completely drained. Doing this will give the seedling its own supply of water deep underground for when it is just planted, as well as encourage vigorous root growth earlier.
Other transplanting considerations
When choosing a location in the garden, make sure you give this plant enough space. A small seedling one year can easily turn into a large 3’ diameter plant the second year. Also, beware of deer/rabbits, as they like to eat the leaves of young seedlings. We use and recommend Liquid Fence Concentrate during the first year it is planted in the garden. For second year or older plants, then I generally apply liquid fence every 2-3 weeks until the plant reaches 1′ (30 cm) in height. From my experience, at least where I live the rabbits don’t seem to interested in larger plants.
This plant will generally not bloom the first year. But if transplanted early enough, I have seen a 1-2 blooms. The second year you can expect to have a strong, vigorous plant that can product 15-40 blooms. So, it will establish quite quickly.
Direct Sowing Echinacea
You can also direct sow this plant in the flower bed/garden. Prepare the area a bit by mixing some compost in about 6″ wide/6″deep area (15 cm X 15 cm). Just plant he seeds (about 5-6) about 1/8″ or 3 mm deep, label it, and then keep an eye out for seedlings/ germination. But – you must make sure it is protected from predators. Rabbits seem to love nibbling off young growth of Echinacea (at least mine!). I would suggest sowing the seeds in April, and just take care of them/protect them. If they germinate in April or May, then they should be able to develop a decent root system by July when the heat sets in (although, use your own eyes to determine if they need extra watering).
Dividing Echinacea, another way to propagate the coneflower
In early spring, when new foliage begins to emerge you can separate and divide Purple Coneflower, and replant the separated section somewhere else. All you need to do is dig up the crown of the root, and cut it in to two equal pieces, or more depending on the size. Then immediately replant the original, and plant the ‘cut’ section where you want another Echinacea. The main reason you should consider doing this is that over time the root crown gets too large, and nothing will grow from the center. This means although you will still have a healthy Echinacea, it will not be as attractive having a ‘dead zone’ in the center of the plant.
General Echinacea Growing Requirements
There isn’t much to this section, as the plant is pretty tough. In general growing Echinacea purpurea is pretty easy. Most coneflowers and Echinacea varieties are pretty hardy once established. It is native to the prairie, where it would receive sun all day, occasional droughts, high wind, etc. The biggest risks are rabbits when the plants are young, or emerging from winter. And putting it in a space that collects too much water, or if it doesn’t receive enough sun.
As is typical with all sun-loving plants, more sunlight will mean larger plants. This plant is best if it can get six hours of sunlight per day from June-August. Also, during extreme heat/drought, it may like to get a bit of water.
What kind of soil does Echinacea need?
Echinacea will do just fine in any soil that is well drained. I would call this plant a true ‘clay buster’ as that is mainly where I have grown it, and it has always been full of blooms and about 4′ tall. Now, that isn’t saying it could grow on a beach, but as long as you can call your yard ‘soil’ I’m pretty sure that this plant can survive.
How to prep Echinacea for winter
Do nothing. It is native to North America, and can take a long hard winter (zone 4-8). Once this plant is done blooming and begins to go dormant, don’t cut it back. Leaving your dead plants up can provide many ecological benefits. The first benefit you will notice with this flower is that the birds, particularly goldfinches, love to land on the seed heads and pick out the seeds to eat. I’ve seen four goldfinches at a time eating seed from plants I have grown. So, it is like a natural bird feeder for your garden! Also, many beneficial insects will hibernate, or have larvae in the hollow stems. Keeping those up will allow them a safe place to over-winter and reemerge in the spring.
However, if it is in the front of your house, then the dead blooms aren’t that attractive. If you wish to cut it back, that will not harm the plant.
Harvesting Echinacea Seed
Saving seeds from Echinacea purpurea is incredibly easy. You should click below to get to our detailed article on how to save Echinacea / Coneflower seeds.
You should try to save the larger, firmer seeds (if practicable). The smaller, thinner specimens may not be viable. But – I am always liberal with the amount of seed I sow, so this generally isn’t a concern for me.
There is one caution I will give you prior to saving seed – if there are many cultivars or species of Echinacea blooming, then be aware that this plant can cross pollinate. So, the seed you save may give you a completely different plant than the ‘parent’ plant you collected from.
Storing Coneflower Seed
For storing the seed, as long as the seed heads had time to dry out in a cool/dry location for a week before separation, then long term storage is easy. Just put them in a zip-lock style plastic sandwich bag, and keep them in a dry area out of direct sunlight, and away from temperature extremes. That’s it – it really is that easy. You don’t need to store them in the refrigerator or anything special. And I’m speaking to you as someone who has only bought one seeds once, five years ago. But, I’ve germinated plants every year since, from seeds I collected the previous growing season. The germination rate for two year old seed is pretty good by my experience, and that is just in a little baggy, stored in a dark location in my house.
Typical Garden Use for Echinacea
This plant is so versatile for any flower bed, it just looks great almost anywhere. For instance, it makes a great ‘center piece’ in a flower bed with taller species such as False Sunflower in the back, and Winecup flower in the front of the bed. It can make a thick, interesting border along your property, and it can even serve as a back border of a front flower bed. The bloom time is so long (approximately 2 months without dead heading) that you should be asking yourself why you don’t have it already! The wildlife it can bring in is incredible, from bumble bees and butterflies to goldfinches swinging on the seed heads. If you have even a passing interest in the bees/butterflies/birds then you should grow at least 3 or 4 of these incredible plants.
Does Echinacea/Coneflowers spread aggressively?
I’ve not seen Echinacea or coneflower be aggressive in any flower bed I’ve grown/maintained. Since the plant is native to so much of North America, a good test as to weather a plant is aggressive is to see how often it occurs in the wild. So, driving through the Midwest you will see specimens every 20-50 yards/meters in the ditch, you probably won’t ever see a field or ditch that is just covered in Echinacea. The fact is, the seed either falls near the parent plant, or is dispersed by a bird. So you won’t see 50+ seedlings within a 20′ radius of the parent plant.