Wednesday, February 3, 2010

An article I wrote some years ago for an Old Roses newsletter

Stop and Smell the Roses’ ….LEAVES!

By John Starnes

How many of us would be so enraptured with, and dedicated to, the rose, if those visually enticing blooms did not also reward a hungry nose with stirring perfumes that linger in our memories on wintry days? The allure of fragrance is a powerful emotion that has undoubtedly helped to make the rose "The Queen of Flowers". Yet many roses offer a potent olfactory treat that many of us may have overlooked (oversniffed?).

If the new foliage and unopened buds of a surprising number of cultivars and species are pinched or rubbed then sniffed, some tantalizing scents may be enjoyed. This added dimension of rose pleasure became more important to me in 1997 after reading some antiquated texts that referred to the familiar ‘Persian Yellow’ as ‘Rosa eglanteria lutea’…so I marched out to my plant in the south hedge of my Denver yard, then pinched and sniffed the new growth and was startled by that familiar apple smell of the Sweet Brier! Interestingly, as I trained a ‘Lawrence Johnston’ in the summer of 1999 in another Denver garden I noticed that its new growth was also apple scented, though more subtley, jogging my memory that it was bred from ‘Persian Yellow’. I will now have great fun trying to establish why ‘Persian Yellow’ and the Sweet Brier ( R.rubiginosa or R. eglanteria) should share that charming aroma of Granny Smith apples…what ancient common origin links them?

During the 1997 Historic Roses Group International Conference in Cambridge, England, Trevor Nottle and I were pleasantly startled by the potent pine-and-medicine aroma of a low growing species in the botanic gardens labelled ‘R. glutinosa’, also known as ‘R. pulverulenta’. It echoed the scent of the Moss Roses but was sharper, like medicinal herbs touched by turpentine. Native to the Mediterranean region, it bears very pale pink 5-petalled blooms that mature into small round hips. Did the arid region impart this foliar pungency as a survival mechanism, perhaps to dissuade foraging mammals and insects? It is worth noting that like R. eglanteria it is a member of the Caninae group of species roses, and it has been suggested in the literature that R. eglanteria is a sport or hybrid of R. canina, a rose noted for odd chromosomal rregularities. Since the Dog Rose is thought to be a remote but crucial ancestor of the large flowered European Centifolias and Damasks and Albas and Gallicas (all of whom can have pine-scented new growth) it may also share a causal kinship to R. glutinosa.

In Colorado, at the Denver Botanic Gardens I sample every summer a large, bushy
pungently-leafed pink flowered species whose identity is uncertain… the odor is
reminiscent of Rosa glutinosa but more floral. Each fall its branches are weighted down with dark orange ovoid hips packed with seeds. A nearby ‘Canary Bird’ bears newly emerged ferny growth offering a subtle, resiny scent each spring.

At two metro Denver cemeteries increasingly known to be treasure troves of "Mystery Roses", are several beautiful roses offering pungent foliar fragrances….at Riverside Cemetery, explored and catalogued for 10 years by now-deceased rosarian Toni Tichy, is ‘Losasso Pink Primula" (possibly a hybrid of R. primula or perhaps R. willmottiae itself) whose ferny foliage virtually reeks of incense when bruised. It bears dense, elongated panicles of lavender-pink single roses potently scented of cinnamon followed by multitudes of small oval red-orange hips that ripen in late summer..the panicles are reminiscent of those of the Potentilla, with the blooms packed all along the length of each arching branch. It suckers VERY heavily and thus many clones of it were taken in 1999 for distribution. The hips were mailed to rosarians noted for their work with species in hopes of establishing its true identity. Toni felt the distinctly lavender shade of pink is an important (albeit charming!) clue.

Also at Riverside is the large-flowered, deep fuchsia and magenta "Obrecht", seemingly a Portland with the Moss Rose scent wafted by its new growth. The nearby Mystery Damask "Evans" also shares this trait. While many of us are not surprised by roses with mossy growths on the buds that are slightly sticky and pine-scented, it can be startling to detect that odor on growth that is barely glandular, as it the case with these large flowered Mystery Roses found in Colorado cemeteries.

In vast Fairmount Cemetery that pungent pine odor is freely released from the rubbed new growth on the large-flowered Mystery Roses "Fairmount Red", "Fairmount Proserpine", "Emmons Damask", "Austin Pink Damask" and the Colorado Gallica called (perhaps erroneously) ‘Desiree’ Parmentier’. Only "Fairmount Proserpine" shares with "Obrecht" the trait of repeat-blooming, so one wonders if the influence of the China roses tends to suppress this trait of scented new growth. (*my ‘Baronne Prevost’, which is predominantly Damask in character but also has a fair dollop of China blood, DOES also have aromatic new growth and buds)These cemetery finds add to the sensory feast with their buxom blooms exuding unique versions each of the heady Old Rose perfume we all adore. The quartered blossoms, lush fragrance, cold hardiness and the suckering habit (only "Fairmount Proserpine" doesn’t sucker) indicate they share a Gallica influence.

In 1998, at the Cranford Rose Garden in Brooklyn, New York, Stephen Scanniello
introduced me to his R. primula, the infamous yellow-flowered "Incense Rose" whose leaves exude an exotic incense-like perfume not for the faint of heart. I can’t help but wonder what wonderful new garden roses might be bred from this cold hardy, living potpourri. Since it originated in central Asia as did R. hugonis (also yellow-flowered and thought to be a parent of ‘Canary Bird’) the link between scented, ferny new growth and yellow single blossoms is worthy of investigation.

It is interesting to note that the simple flowered species types mentioned above can exude the scent from nearly all the leaves and buds, (though the potency of new growth is far greater), whereas the large-flowered "Mystery Roses" with their sumptuous Old Fashioned blooms limit their foliar fragrances to the newest tip growth and unopened buds…older leaves, when crushed, simply have a "green leaf" smell. Since the larger-flowered Eglanteria hybrids like ‘Anne of Geierstein’ and ‘Amy Robsart’ and ‘Goldbusch’ and ‘Applejack’ all have a much fainter apple scent to their leaves, it would seem this trait is recessive. (Note the parentage of the very appley scented Penzance eglanteria hybrid "Lady Penzance"…R. eglanteria X Persian Yellow….both parents exude the apple smell). Insects can be voracious during the short growing season that these scented small-flowered species are native to, so perhaps these odors are natural repellents akin to those of the marigold and onion.

As a bi-climate rosarian who divided my time between Colorado and my native Florida for fifteen years, I have yet to encounter any mild climate roses with fragrant foliage…could those essential oils be a protective adaptation to severe winters? Despite their apparent need for winter dormancy I am planting a number of these species in Tampa in hopes of providing Florida rose lovers with a new source of rose pleasure but also to incorporate into my mild climate breeding work the potential for scented leaves IF they adapt. If these oils DO have insect repelling qualities, that should be apparent in this subtropical region teeming with plant feeding insects. And it will be interesting to note that IF the plants adapt and become perennial here as in Colorado, will the pungency of the scented leaves increase or decrease in these hot, humid conditions?

I would be very pleased to hear from any of my comrades of other roses with this extra measure of pleasure. So I encourage you all, in your busy schedules, to
occasionally just stop and smell the roses’….leaves!

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