trailing rosemary (Rosmarinus officinalis ‘Prostratus’)
In Acciaroli, a remote fishing village in southern Italy, around 15% of the population (300 out of 2000 people) are at least 100 years old. This fact aroused the curiosity of Alan Maisel, professor of cardiology at UC San Diego.
So Maisel took a trip to Acciaroli as a member of “the first group of researchers to be given permission to study this population.” Before getting down to basic research, which will involve taking blood samples and mapping out genetic markers for longevity through DNA analysis of the centenarians, Maisel mingled with the locals, observing their habits and diet. Astonshingly, he found that most of them were smokers and the majority were overweight.
One of Maisel’s first observations concerned the ubiquitous presence of rosemary in the food that they ate. “Everybody eats rosemary,” Masiel reported. “They all grow it, they use it as a garnish, they use it in oils.”
The UC San Diego group is working in conjunction with the Sapienza University of Rome. Salvatore Di Somma, a professor of internal medicine at this university, notes that “rosemary is very diffused here (in Acciaroli) and has been shown to have metabolic benefits for longevity so it is one of the strong factors of many we are looking at.”
Dozens of scholarly, peer reviewed scientific studies have been published regarding the beneficial effects of rosemary. At Kansas State University, for example, it was concluded that rosemary extracts, when mixed with ground beef, prevented development of “cancer-causing compounds produced when meats are grilled, broiled or fried.” Take home lesson: before you barbecue your burgers, make sure you add a significant dose of rosemary to your ground beef.
A study published in the International Journal of Neuroscience revealed that misting of cubicles of test subjects with rosemary oil enhanced their overall memory and alertness. Numerous studies suggest that regular consumption of rosemary may combat the onset or advance of dementia and Alzheimer’s disease.
The best part of all this, from a gardener’s perspective, is that no plant is easier to grow than rosemary. Rosemary is happy in full sun but can also thrive in partial shade. Traditional rosemary (Rosmarinus officinalis) is an upright species that may reach six feet in height and is adorned with sky blue flowers for many months. But there are other rosemary types worth planting, including cultivars with dark blue (such as ‘Tuscan Blue’), pink, and white flowers as well as ‘Golden Rain,’ which features green foliage with gold margins. There are also trailing. ‘Prostratus’ rosemary varieties that do not exceed two or three feet in height and are a wonderful selection for erosion control on slopes.
I have noticed that my own mature, mulched rosemary shrubs have gone through this very hot summer with no more than a single soaking each month. I would even go so far as to say that had they not been watered at all this summer they might have done just fine with the 9.65 inches of rainfall (albeit significantly less than our 14.77 inch annual average) that were recorded during the past year.
The one absolute rosemary requirement is well-drained soil. I have seen rosemary die after heavy late winter rains followed by warm temperatures. Such conditions are ideal for activation of Phytophthora water mold fungi, which will quickly kill rosemary and other Mediterranean climate plants, including many California natives, where soil drainage is imperfect.
In truth, clinical trials have demonstrated the therapeutic effect of a wide spectrum of essential herbal oils, whether derived from rosemary, lemon balm, sage, lavender, or marjoram in the treatment of Alzheimer’s symptoms. The effect is not olfactory with certain oils, since many Alzheimer’s patients have lost the sense of smell but respond positively when herbal lotions are topically applied.
Hibiscus ‘Haight Ashbury’
When it comes to horticulture, you never know where you might see something you have never seen before. Just the other day at Ralph’s Supermarket on Magnolia Boulevard in Sherman Oaks, I was introduced to Hibiscus ‘Haight Ashbury,’ on display among a mélange of ornamental plant offerings outside the store. This cultivar has foliage that looks more like Japanese maple than hibiscus and leaf pigmentation includes splashes of pink and white against a burgundy background.
Here’s an encouraging word about hibiscus in general. Since the early 1990’s, when giant whitefly first arrived in Southern California from Guadalajara, Mexico, this sucking insect has been a nightmarish pest, coating foliage of susceptible plants – especially hibiscus and xylosma — with a layer of white fur that resembles laundry lint, but is actually a collection of waxy, threadlike filaments produced by whitefly nymphs. This is the first summer I can recall in over 25 years where no giant whiteflies on my neighborhood hibiscus have been seen. It would appear that the control of giant whiteflies may be explained by releases of certain parasitic wasps, their natural predators, or perhaps the drought has something to do with the blessed disappearance of this pest.
Echeveria ‘Red Velvet’
Tip of the Week: Speaking of finding new plant varieties in unexpected places, I was pleasantly surprised to discover Echeveria ‘Red Velvet’ in the nursery at Gelson’s Market this past week. For years, I had marveled at Echeveria pulvinata, noted for its fuzzy gray leaves edged in red and long-blooming clusters of orange flowers. This new variety must be a close cousin except for its somewhat more fiery blooms. Grow ‘Red Velvet’ in half-day sun and keep water off the foliage, during hot weather, for best results.
