In 2000 the horticultural world turned upside down with the introduction of a new rose. Its registration name was ‘RADrazz’, but it became known to the world as ‘Knock Out’. Sixteen years later, it is probably the most popular rose in the United States, if not the world.
On the face of it, ‘Knock Out’ appears pretty but not extraordinary. The flower petals have often been described as “cherry red”, with five to fifteen per flower. Categorized as a shrub or landscape rose, ‘Knock Out’ grows up to four feet tall and wide, but can be kept smaller. Supposedly it has a light, spicy scent, though I have rarely detected any scent when the blooms have come near my nose. On appearance alone it cannot compare to real beauties of the rose world, like peachy-pink ‘Abraham Darby’ or ‘Sally Holmes’, with its gorgeous, single white blooms.
So what is all the hype about?
‘Knock Out’ has been touted as the closest thing to no-maintenance rose. The subject of many rose trials in many places, it has proven to be pest and disease resistant and able to thrive under a wide variety of conditions, including light shade. It reblooms prolifically throughout the season. Texas A&M University included it in their list of Earth Kind ® roses, signifying that it met their stringent requirements for superior performance without the need for chemical intervention. It has lived up to most of the hype, getting along fine in situations ranging from the well-tended rose beds of botanical gardens to the frequently-neglected median strips of large shopping malls. Homeowners from Bakersfield, California to Bangor, Maine have grown the shrubs successfully in flower beds and large containers. Anyone anywhere can grab a ‘Knock Out’ off the shelf at the local mass merchandiser, take it home, plant it in a reasonably sunny spot and get decent results. In full bloom the flowers are cheerful and eye-catching.
It is hard to begrudge a rose with that many virtues. However, I will never grow it.
Life may be full of sunny days—unless of course you live in England—but my yard is not overflowing with sunny space. Any rose worthy of taking up some of that sunny space must have rare beauty, fragrance and the ability to survive on a diet of neglect. Since ‘Knock Out’ does only one of those things, I can’t find a reason to include it. For fragrance I would rather tickle my nose with the likes of ‘Zephirine Drouhin’, a rose-pink climber with an intoxicating scent. In my yard, at least, the plant is untroubled by black spot or mildew. Its climbing habit means it takes up fairly little horizontal space, which is another plus. The blooms are elegant and appear several times over the course of the season. It also beats ‘Knock Out’ on another count—thorns. ‘Zephirine Drouhin’ is virtually thornless, while ‘Knock Out’ has plenty of thorns.
‘Knock Out’ has great utility as a landscape shrub and is often planted en masse for dramatic effect. From the marketing materials, you would think that it is the only rose suitable for this purpose. This is untrue. One of my favorites, the fragrant hybrid musk ‘Buff Beauty’, works nicely as a landscape shrub, combining toughness, good looks and vigorous growth. The buds are yellow with just a hint of peach and the flowers open pale yellow, aging to white. I have never sprayed mine for any reason other than to repel deer and it has flourished for seventeen years.
By the way, ‘Knock Out’ may not get black spot, but it is no more deer resistant than any other rose. Mr. Antlers and his vast family clearly have not read the advertising copy.
To my way of thinking, ‘Knock Out’ and its many progeny, all of which bear the ‘Knock Out’ name, have no romance. Now, a rose cynic or a ‘Knock Out” vendor might counter with the argument that there is nothing romantic about a rose that needs excessive coddling just to produce a few perfect flowers. That is absolutely true. But intelligent rose lovers have always found shrubs that rank high on the scale for beauty and fragrance scale and low for maintenance. ‘Golden Celebration’, one of the best of David Austin’s English roses, bears repeated flushes of golden roses on extremely vigorous bushes. If you buy “own root” rather than grafted bushes, the shrubs will even grow back true to type after the top growth has been killed by hard freezes. My ‘Golden Celebration’ even came back strong after Hurricane Sandy, when high winds tore off its strongest canes.
‘Knock Out’ boasts of continuous bloom and it may have an edge over other reblooming varieties, producing more flowers more regularly. This is a plus in a landscape setting, but not so important that I am willing to sacrifice the romance provided by reblooming varieties with a slightly smaller output. After all, if I want roses that are always in bloom and perpetually perfect, I can buy plastic ones. All they ever need is dusting.
The choice, of course, is up to every gardener and there are no bad choices if you are happy with the end result. My avoidance of ‘Knock Out’ roses will have absolutely no effect on global sales and will, in fact, leave more for the people who love them.