by Nanette Londeree, Master Rosarian
What in the world are single roses? Roses that grow individually on a stem or plant? Roses that like to grow alone? Well, neither – when we refer to “single roses” we are referring to the form of the flower, in particular the number and arrangement of the petals. Petals are the most visible portion of the flower, and a rose can have anywhere from no petals, like Rosa chinensis viridflora, known as the “Green Rose”; it has no petals at all – it is actually covered by lots of sepals, to many old garden roses and English roses that may have more than 100 petals. The number of petals, or petal count, is a measure of the fullness of the rose. Single rose are defined by the American Rose Society to have between four and eight petals, while roses categorized as semi-double have nine to sixteen petals, double blooms have 17 – 25 petals, full blossoms are 26 – 40 and very full are 41 or more. More than forty-one petals sounds like a lot, but in the world of roses, it isn’t all that many.
All roses were originally singles, composed of five petals, with the exception of one four-petaled species. As natural mutations occurred that replaced stamens and pistils with additional petals, semi-double and double roses appeared. These growing oddities (at the time) were saved and propagated by gardeners. Flowers of hybrid teas, floribundas, and other rose classes with China and Tea roses prevalent in their ancestry have a lower petal count, but their petals are larger and longer. These mature flowers have a much looser appearance than those of the Old Garden Roses. Today, a double rose with 17 – 25 petals is the norm.
I began my romance with single roses many years ago – it was their wonderful simplicity that attracted me initially, and then I found out how easy they were to care for. The fuller the flower, the longer it takes to open, and if there is any moisture around, they can “ball” up and never open at all, or worse yet, they can tend to attract Botrytis Blight and rot on the plant. While that is extreme, most roses with very full blooms don’t open unless they get a lot of heat. With few petals, the rose opens easily, and many of the plants are “self-cleaning” meaning that they drop their petals when they are spent, and there is less need for deadheading right away to keep the plants looking good.
There is a long list of outstanding single roses that come from just about every type of rose from species and hybrid musks to hybrid teas and miniatures. They also come in lots of colors. Here are a few dozen roses that ARS members rate very highly:
| Name | Type | Color | ARS Rating | Year Introduced |
| Dortmund | Hybrid Kordesii | Medium Red | 9.3 | 1955 |
| R. rugosa rubra | Species | Mauve | 9.1 | 1784 |
| R. rugosa alba | Species | White | 9.1 | 1811 |
| Alba Semi-plena | Alba | White | 8.9 | before 1867 |
| Golden Wings | Shrub | Light Yellow | 8.9 | 1956 |
| Irish Elegance | Hybrid Tea | Orange Blend | 8.9 | 1905 |
| Kiftsgate | Species | White | 8.8 | 1954 |
| Lyda Rose | Shrub | White | 8.9 | 1994 |
| Mutabilis | Hybrid China | Yellow Blend | 8.9 | before 1894 |
| Sally Holmes | Shrub | White | 8.9 | 1976 |
| Complicata | Hybrid Gallica | Pink Blend | 8.8 | no date |
| La Marne | Polyantha | Pink Blend | 8.8 | 1915 |
| Nevada | Hybrid Moyesii | White | 8.8 | 1927 |
| Robin Red Breast | Miniature | Red Blend | 8.8 | 1983 |
| Ballerina | Hybrid Musk | Medium Pink | 8.7 | 1937 |
| Kathleen | Hybrid Musk | Light Pink | 8.7 | 1922 |
| Dainty Bess | Hybrid Tea | Light Pink | 8.6 | 1925 |
| Knock Out | Shrub | Red Blend | 8.6 | 2000 |
| Poulsen’s Pearl | Floribunda | Light Pink | 8.7 | 1949 |
| My Sunshine | Miniature | Medium Yellow | 8.6 | 1986 |
| Pink Meidiland | Shrub | Pink Blend | 8.6 | 1984 |
| Altissimo | Large-Flowered Climber | Medium Red | 8.5 | 1966 |
| Frau Dagmar Hartopp | Hybrid Rugosa | Medium Pink | 8.5 | 1914 |
| Fred Loads | Shrub | Orange Red | 8.5 | 1968 |
| Fruhlingsmorgen | Hybrid Spinosissima | Pink Blend | 8.4 | 1942 |
| Eyepaint | Floribunda | Red Blend | 8.4 | 1975 |
| Mrs. Oakley Fisher | Hybrid Tea | Deep Yellow | 8.3 | 1921 |
| Playboy | Floribunda | Red Blend | 8.5 | 1976 |
| R. eglanteria | Species | Light Pink | 8.4 | before 1551 |
| Simplex | Miniature | White | 8.4 | 1961 |
| Playgirl | Floribunda | Medium Pink | 8.4 | 1986 |
| Betty Prior | Floribunda | Medium Pink | 8.2 | 1935 |
| Carefree Delight | Shrub | Pink Blend | 8.2 | 1994 |
| Dusky Maiden | Floribunda | Dark Red | 8.2 | 1947 |
| Hoot Owl | Miniature | Red Blend | 8.2 | 1990 |
I have the good fortune to grow most of the roses on this list, and with minor exceptions, I can say that they generally perform better than roses with more petals. While the number of petals certainly has a lot to do with it, it is also related to their heritage, and since many are hybridized from species like R. eglanteria, the “Sweet Brier Rose” and of R. spinosissima, the “Scotch Rose” that have proven durability, they are hard to beat. You can grow ones like Kiftsgate that grows easily to 10 by 20 feet and is spectacular in bloom, to more modest sized versions like Mrs Oakly Fisher, staying about four feet tall, covered with thick, lush foliage that begins a rich plum color that is a great contrast to the apricot blooms. Regardless which you choose, you can’t go wrong with singles!
Photo of Complicata used with permission by © Wendy Annibell, Long Island, NY