A reader, matt d. reed, just informed me that the beautiful Bello Grigio® (Stachys Bello Grigio), my favorite 2016 annual (read A Silver Fountain for the Garden) and winner of many international awards in 2016 and 2017, is actually being sold under the wrong name.
It turns out not to be a stachys (Stachys) after all, but rather a Senecio known as white arnica (Senecio niveoaureus). In other words, it’s a close relative of the popular garden annual Dusty Miller (S. cineraria, now Jacobaea maritima) and in no way related to lamb’s ears (Stachys byzantina). The genus Senecio, in the Sunflower family (Asteraceae), has a worldwide distribution and, with more than 1200 species, is one of the largest genera of flowering plants in the world.
This isn’t a terribly surprising change. Yes, the silvery-white fuzzy leaves may look a lot like those of lamb’s ears, but the genus Senecio also has many furry, silvery plants. In fact, the name Senecio is Latin for “old man,” referring to the abundant white hair so typical of the genus.
Its Flowers Gave It Away
How was the mistake discovered? The plant bloomed in a few greenhouses last winter and the attractive yellow inflorescences are clearly typical of Senecio flowers, looking rather like small sunflowers, and absolutely not like the two-lipped flowers of the genus Stachys (Lamiaceae or mint family). It was then just a question of matching the flowers and foliage with known species of Senecio.
The More You Know…
This discovery will help gardeners better understand how to grow what is now Senecio niveoaureus Bello Grigio, as we can now trace its origins. (Until recently, it was assumed to be a greenhouse hybrid … definitely not the true situation.)
The species, known as white arnica, comes from the páramo of Colombia and Ecuador, a high-altitude tundra zone found at about 10,000 to 15,000 feet (3100 to 4600 m) of altitude in the Andes, a climate where it is cold at night all year long and rarely more than chilly during the day. If the plant is completely covered with white hairs, that’s partly to protect it from the cold, but also to filter out excess sunlight, because it usually grows above the clouds, fully exposed to harmful UV rays.
Just by experimenting with this plant, originally sold as an annual, many gardeners have already learned that you can actually keep it alive indoors over the winter on a sunny windowsill. It does all right there, but comes out looking a bit weakened by spring. However, we were assuming it was a tropical plant and needed warm conditions.
Knowing that it is a high-altitude plant used to the cold, we can now assume it will probably prefer cool fall temperatures outdoors through the fall, then can be brought indoors only when there is a risk of frost. (In fact, it will likely be able to take quite a bit of frost.) At that point, look for a brightly sunny and cold but nearly frost-free indoor location. An alpine greenhouse, for example, would be perfect.
Of course, this plant is already spectacular enough to be grown simply for its soft and silver foliage, but if it can also bloom indoors too … well, who wouldn’t want to see that!
Seed is Available
There is another benefit of knowing this plant’s real name. It turns out it is available by seed … and indeed, has been for years. Knowing that, you’ll be able to buy seeds of S. niveoaureus (notably from Sunshine Seeds) and then grow it at a lower cost compared to when it was uniquely sold as Bello Grigio, only available through cuttings and divisions.
Getting the Name Right
Still, isn’t it annoying that growers continue to launch plants on the market without bothering to do any research into them? It seems to me that the least thing you should expect to when you buy a new plant is a label with the right name!