Friday, December 19, 2008

HIP HIP HURRAY
Think of This Hardy Rose as a Shrub

By Rachel Foster 10/11/07

My favorite rose has no scent that I've noticed. The flowers, single and a bit small, are not my favorite color, and their bloom lasts only a few weeks. So why do I think you might want to grow this plant? Think of it as a shrub, rather than a rose, to re-align your expectations. There are two botanical names for it, Rosa glauca and Rosa rubrifolia. I am not sure which is currently favored by botanists, but I call it by the name I learned first and consider most descriptive: R. glauca. The adjective glaucus, from the Greek, is defined as bluish gray or bluish green. Bluish, greenish gray describes the leaves perfectly. Rubrifolia means red-leafed, which is a bit of a stretch, although the leaves are purplish when they first expand, especially in sun. The midribs in the leaves are also red, and so are the young stems.
The color of the leaves, however you perceive it, is this shrub's number one attraction, but there are other things to like about it. Five-petaled flowers, though small, occur in clusters and are numerous enough to make a good showing. Each petal is a strong pink, fading to white towards the center of the flower, creating an interesting effect that is somehow lively. Later, in August through October, comes an impressive show of fruit (called hips, in roses) that start out brown and slowly turn rust-red. All this time the lovely foliage continues in un-roselike good health. You won't see much alteration in the leaves until October, when they fade to creamy yellow.
Rosa glauca will grow in any reasonably bright location. Specimens growing in full sun have the best show of flowers and fruit, while plants in light shade have the most beautiful, glaucus leaves. The plant grows to 6 or 7 feet in an arching form that allows you to underplant it with smaller shrubs or (for instance) billowing hardy geraniums and catnip. Removing older stems from time to time keeps it from turning into a big round bush, and pruning is followed by a flush of gorgeously colored new growth. Some gardeners remove most of the older growth every year to promote long shoots with especially luxuriant blue leaves. You won't get as much bloom or fruit this way though.
This is a versatile plant seems as much at home in stylish gardens with New Zealand flax, honey bush and canna lilies as it does in lower key company of Aster frikartii and daylilies. I am currently trying to come up with a way to combine it with white or light pink Japanese anemones in my garden. Not particular as to soil, this rose, like many species roses, is rather drought tolerant. It is nearly impervious to disease in most gardens, even when stressed. This drought resistance suits it to combining with such xeric looking plants as yucca, silver Senecio 'Sunshine' and tall sedums. Crimson barberry picks up the red of the stems and midribs nicely.
There are, of course, other roses that may produce a showy crops of hips. Most have single or semi-double flowers, not the fully double flowers of the hybrid tea rose. Two standouts are pink-flowered Rosa rugosa 'Frau Dagmar Hastrup,' with green crinkled leaves and big, shiny red hips on a compact plant; and the towering R. moyesii, with red flowers and elongated fruit an inch and a half long. Roses that bloom only, or mostly, once a year as old roses, ramblers and many species do are good candidates. Our own wild native roses, such as Nootka, bald-hip and clustered rose, have quite decorative hips.
Hybrid musk roses, bred in the first third of the 20th century for recurrent bloom, are well known for producing a late flush of bloom in September. Some are also reliable fruiters, one of the best being 'Penelope,' whose hips are large, coral pink and last a long time. 'Darlow's Enigma' is a tall, wonderfully healthy, cream-flowered shrub rose or climber that originated by chance in Eugene's Owens Rose Garden and is now known nationwide. It shares some of the qualities of hybrid musks and is often listed with them although it is much more fragrant and more continuously in bloom than most. 'Darlow's Enigma' delivers sprays of salmon-colored, tiny hips that hang on well into winter.
You won't, of course, get rose hips if you deadhead too assiduously. Fortunately, most good hip producers have the sort of flowers that drop their petals, so you don't have to endure dead flowers for very long. Some roses can be deadheaded after the first heavy bloom and still produce hips from whatever flowers come later (my strategy with hybrid musk roses) though you won't get quite the same result as if you postpone all pruning until February.