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Entries in Rainbow Knock Out Rose (5)


Two Full Disclosures About my Favorite Plant, Rainbow Knock Out Rose

July is a brutal month for most perennials. It is also the time when even the most floriferous of roses will take a break from putting on impressive displays. My favorite rose, Rainbow Knock Out, is not spared this intermission; during this past July, I was finally able to witness how it coped with the temporary transformation brought on by the heat of summer. It was not a pretty sight and my observations might help to explain why this otherwise amazing rose bush is not popular anymore with garden center owners.  

The first image demonstrates how beautiful this bush can be in the temperate weather of early summer.

The second image shows what it looks like in July. By then, the vivid coral blooms fade to white and the shimmering gold centers turn brown. My rose bush maintained this less-than attractive, white and brown appearance during the entire month of July and began to revert back to its coral glory only in August.

One may correctly presume that a prospective consumer, browsing through a nursery in July, might not be drawn to a plant putting on such a faded display. The “shelf-space” occupied by any plant is critical to encouraging customers to shop and this rose cannot “pull its own weight” when it looks so tepid. If I were a nursery owner, I, too, would be eager to replace this rose with a more attractive-looking plant.

So, what does this mean for the gardener who adores this rose, in spite of its shortcomings? Rainbow Knock Out will work just fine when it is planted among, and surrounded by, colorful July-blooming plants. Its faded appearance might be mistaken for an anonymous white perennial inserted into a garden composition; it will hardly be noticed. Conversely, do not plant this rose all by itself, as a specimen, because that is when its shortcomings become blatant.

This is the third time that I post about Rainbow Knock Out Rose. Some readers might erroneously believe that I have a vested interest in the marketing of this plant. Therefore, in full disclosure, I report that, because I live in Canada, I have no opportunity to either receive any freebies from American growers [who ship awesome plants across the border to my suppliers], nor am I able to enjoy the company of their public relations representatives at garden writers’ conventions. Since blogging is a labor of love, I cannot justify the expenses associated with attending these events. I pay for my own plants and write about them whenever they enchant or inspire me.

P.S. Since I first wrote this post, Eileen, who garden blogs at Gatsby's Gardens has reported on her site that her Rainbow plant grows rather large and that, after the first bloom, she has contained its volume by shearing it down a size or two without affecting its floriferousnes.


A Perennial Garden Will Always be a Work in Progress

When designing a perennial garden, one cannot predict with certainty how it will grow during the following season. Sun, rain, temperature, soil conditions, location, borrowed views, and a plant’s naturally - determined personality will interfere even with the most experienced gardener’s vision. Editing a flowerbed, in seasons to come, is an integral part of the design process.

The photo above demonstrates a late May-early June combination from this season that was planted last year. While it creates a satisfying visual composition, it is not growing as spectacularly as envisioned in the original plan on paper. From left to right, one can see Salvia Caradonna, Rainbow Knock Out Rose, Itoh Peony Bartzella and Iris sibirica Caesar’s Brother. A vivid pink Silene Rolly’s Choice grows in the background but it is unintentional to the composition.

For better results, the rose ought to have had more blooms on it; the purple siberian iris ought to have been growing behind the yellow Itoh peony for a more vibrant color effect and the purple-blue Salvia ought to have been closer to the rose. Except for moving the iris, the other “ought tos” are not realistic options in the narrow flowerbed that flanks a walkway. In fact, Salvia Caradonna is such an impressive perennial that by the beginning of July, it became necessary to move it to another spot in the bed where it could flourish without overpowering the garden. Furthermore, in USDA Zone 4, the rose will only pump out more blooms in early July.

Since shooting this photo, the taller purple irises were lifted and placed behind the shorter yellow peony. The intention is to create a more dramatic composition. Perhaps in their new location, the irises will contribute visual excitement when they bloom in tandem with the coral roses.

My only regret in posting this photo is that Itoh Peony Bartzella is not a friend of the camera. The bright lemon yellow saturation of its petals is so intense that light bounces off the flower, even on an overcast day. It is quite a challenge for this neophyte photographer to capture a satisfying image of this very unusual and dramatic plant.

Even with the generous advice of skilled photographers, at this time of year, garden projects leave so little time to learn how to use the camera properly. I am sure that one can control for this bleaching-out effect if one takes time to read the owner’s manual provided with the camera. With only modest results, I have relied upon the editing feature of Zoombrowser to improve the appearance of the yellow petals. My consolation is that instead of mastering my Canon Power Shot, I gave homeowners the garden of their dreams.


The Frog Prince in my Garden

Photo is the copy-write property of allanbecker-gardenguru.The Rainbow Knock Out Rose is one of the most important plants in my repertoire and the most difficult to find. Last year, it was available from only two wholesalers in my region who reached a  sold out position by mid season. Half way through, what turned out to be a bumper year for my garden design business, I had to source it from a big box store. Although the plants were scrawny and, for my purposes, overpriced, I had no other choice but to purchase every one that I could find. I promised my clients that the unimpressive diminutive plants, that appeared, at first, to add nothing to their newly designed gardens, would knock their socks off by the following year. 

A garden writing colleague had mentioned that in her region, a similar unavailability occurred. She reported that most retail nurseries refuse to stock it because Rainbow Knock Out Rose doesn’t show very well in its pot. That is true. It is a Frog Prince in the garden. Not only is it unattractive at point of sale but until it produces its first full flush of blooms, it resembles an ugly brambly bush. However, once it starts pumping out multi-hued coral roses, it becomes a prince as it takes visual ownership of the flower bed.

Unfortunately and realistically, no nursery can expect to do business by promising the consumer to take a chance or to wait and see. Consequently, most refuse to buy and miss out on a great and pleasurable visual experience. I am fortunate that my clients trusted me; they have not been disappointed. Some have asked me to plant additional Rainbow Knock Outs after watching the first one develop. 

Imagine an almost spherical shrub, 3 feet high and wide, completely coated in many hues and shades of pink, yellow, coral and blush. It resembles a giant luminous scoop of bubble gum-peach ice cream. For those who live in temperate climates, that might not be such a big deal. Just south of where I live, in the warmer parts of the United States, gardeners have a wide selection of warm, tropical-colored flowering plants that bloom impressively at various times of year. By comparison, the cold climate gardener in USDA Zone 4b, has very few of these experiences. That is why the contribution to the garden of Rainbow Knock Out Rose is so significant. 

How sad that a plant that delivers such a moving experience to the patient gardener should be so unattractive at point of sale that it is removed from market. Perhaps it should be tagged with a luxurious glossy image attached to a plastic wand stuck into the pot. The Endless Summer series of Hydrangeas are marketed that way and I believe that Rainbow Knock Out would benefit from a similar treatment. However, growers should pay special attention to the quality of the photograph that they use. The consumer needs to see two images:- one, a close up of the rose when it is still a deep coral color and two, an image of the shrub coated in multi-hued flowers. 

On the other hand, I’ll bet the breeders are now working to develop an improved Rainbow Knock Out that will present well at retail. In the gardening business, the market is a powerful and influential force that drives change. Meanwhile, I will continue to hunt and collect as many of these roses as I can. This plant belongs in the category of takes your breathe away.


Update on Knock Out Rose "Rainbow"; don’t walk, to your nearest garden center to buy the Rainbow variety in the Knock Out Rose series before it is sold out and while it is still safe to plant. I added it to my test garden at the beginning of the season to see how it would perform. [See my blog entry of May 19, 2009.] And perform it did. It blooms floriferously.

Gardening colleagues report that by year three, after the first bloom of the season, the volume of this shrub was enormous and that it became necessary to shear downits shape by a size or two. The haircut did not affect its subsequent flower power in the weeks that followed.

For most of the growing season, the entire rose bush is covered with the most delightful shades of coral flowers with subtle yellow centers. Each batch of blooms is more numerous than the one before and the color intensity is both striking and moderate at one and the same time. I was unsure if coral would blend well into the garden and that turned out to be an unnecessary concern.

This enchanting plant integrates well wherever it is placed and draws attention to itself with its unique color saturation. Don’t be afraid to mix this rose bush into any color scheme. You won’t be sorry that you did.


Rainbow Rose Is a Knock Out


While browsing through the catalogue from my Rose supplier, I came across thisvivid-colored Rose called Rainbow. I ordered it because there is always a demand for tropical colored flowers. I had earmarked it for the garden of a particular client but after it arrived, I had a change of heart.

While unpacking it, I glanced at the color photo tag attached to the neck of the plant and was, once again, so impressed with the photo that I decided to grow it in my garden instead. I need to confirm if this plant will live up to the promise of its picture.

The Knock Out Rose series is considered to be the most disease resistant Rose collection on the market. Rainbow, is another cultivar in that series. Although it is a compact plant growing three feet high and wide, it is a prolific bloomer if fed and watered regularly. It grows well in zones 4 to 9.

The flower is a delicate single form blossom that starts out with a coral pink bud that opens to orange then quickly turns to soft coral pink shading to gold at the base, surrounding a yellow center. As the flower matures, it fades to light coral. What makes this plant magnificent is the multicolor presentation when in full bloom. Imagine looking at this shrub and seeing the various colors of the bud, new bloom and mature flower all at the same time. This is a self cleaning plant. There is no need to deadhead spent flowers.

Click here to find out how this rose fared in my garden.