Many gardeners are disappointed with the new echinaceas, formerly called purple coneflowers (Echinacea cvs), that have dominated the horticultural market over recent years, the ones that come in new colors (red, orange, green, and yellow) and forms (double, semi-double, etc.). They claim they are not as cold hardy as they are claimed to be, the proof being they repeatedly lose their plants over the winter.
While it is certainly possible that some of these new varieties might not be very hardy (you’d have to do a thorough side-by-side test to tell), that’s not the real source of the problem in most cases. With proper treatment, pretty much any echinacea will thrive in zone 4, and most in zone 3 as well, and that’s pretty hardy.
Instead, look into how echinaceas are now grown for the cause of so many failures.
Sold Before Their Time
You see, garden centers sell more echinaceas when they are in bloom. And their main selling season is in May and June, yet echinaceas normally bloom in late summer or fall. To fix this, they offer plants that were specially treated in greenhouses to bloom outside their normal season. That’s why when you go plant shopping in May or June, you find a wide selection of coneflowers in full bloom. But there is a price to pay for this early flowering.
You see, forcing a plant (giving a plant special treatment so it blooms outside its normal flowering period) disrupts its growth. It creates considerable stress on the plant, reducing its overall resistance. In addition, plants that are planted while they are blooming don’t tend to develop a very good root system, since they’re putting all their energy into flowering… and yet, a good root system is vital to ensure winter survival.
What makes forcing especially harmful to echinaceas is that it is often practiced on young plants fresh out of the tissue culture laboratories where they were produced. In the past, these plants would have been grown on for a full year, then sold, without bloom, the following spring. But instead they’re forced to bloom after only a few months of growth, way before their time.
That’s why your new echinacea – in bloom too young, too early in the season, and with a very limited root system – really isn’t ready to undergo the rigors of a harsh winter.
Flowers on the Chopping Block
What can you do to counter this?
I scarcely dare say this, as I know it will disappoint many readers, but when you buy a young echinacea in bloom, especially outside its normal season, the best thing to do is to remove all the flowers before planting it. (Or afterwards, if you’ve already planted it). In fact, for top results, simply don’t let it bloom at all the first year, even if it isn’t in bloom at purchase time.
By preventing your young echinacea from blooming the first year, it will no longer lack energy, but actually have more than it needs, a surplus it can instead invest in producing a strong root system and a rich reserves of carbohydrates for next year’s blooms. The resulting plant will be much more resistant to harsh winter conditions, giving you a plant full of energy that will bloom massively… and at the right season too, that is at the end of the summer into fall.In addition, this “first year sabbatical” will give you a plant more inclined to live a long time, even many years after the treatment, usually a decade or more.
Therefore, gardeners, to your pruner shears! Removing the first-year flowers of your echinaceas will ensure a robust, floriferous and long-lived plant that will show its true winter hardiness and give you great results for years to come.
It Works on Other Plants Too
The same principle applies to most other perennials and even to shrubs and trees: they will all be more vigorous and floriferous in the future if you don’t let them bloom the first year. Give them time to settle in before putting them through the rigors of what is, for the plant, an energy-stealing activity.
This is doubly true for perennials that are reputed to be short-lived, like gaillardia or blanketflower (Gaillardia x grandiflora). If you want these plants to survive the winter and live for at least a few years, just don’t let them bloom the first year.
Would this be the same reason that Delphiniums don’t live long?
Actually, delphiniums can live for decades… under the right conditions. They are cold climate plants. They’re short-lived in climates with hot climates, especially hot dry ones.
Really helpful, thanks! Explains why of the two I bought on clearance last year, the only one to come back was the one struggling so bad I cut it back.