Fall bloomers always catch my attention – not only do they provide interest and color when a lot of other plants are still just waking up from summer-dry semi (or total) dormancy, but they also celebrate what I consider to be the ‘start’ of the natural year in mediterranean climates – when the rainy season begins!
Arum pictum, the subject of this article, is the only fall blooming in its genus. In the original version of this article, published in September 2010, I mentioned that I was interested in growing this species myself, but was having trouble locating it in the trade. In response, one of my readers contacted me and, to my delight, eventually sent me some tubers from his own planting which was growing happily in his garden near Sacramento (in California’s Central Valley).
I have been growing Arum species for many years and I liked the idea of a fall blooming species with the flowers opening at the same time that the foliage is fresh (other spring bloomers flower when the foliage is looking tired or already starting to go dormant). That the range species is squarely in the Mediterranean – Corsica, Sardinia, & the Balearic Islands – aligned with my interests in understanding how plants adapt to the mediterranean climate.
Here is what Peter Boyce, the well-known authority of the genus Arum, has to say about this species:
“The leaves of A. pictum display a variety of colours, depending on the stage of development reached. On first emerging they are a deep, shiny, metallic green, with the margins . . . tinged with purple. As the leaf expands the purple . . . coloration fades while the main and lateral veins become slightly paler; the margin however retains its coloration. As the season progresses . . . the veins continue to lighten until late spring, when they stand out as a creamy-white to silvery-grey network. The late season coloration of A. pictum leaves is similar to the silver-grey veining of many forms of A. italicum, although the leaf shape is very different. In view of this similarity it is hardly surprising that these two plants have been much confused in the past. In addition to its attractive foliage, A. pictum produces spathes at the start of the growth period in the autumn, a flowering pattern which is unique to this species.
“Arum pictum was first described by Linnaeus the younger from material gathered on Corsica, where it occurs in stony or rocky places or beneath low scrub.”
As Peter Boyce mentions, there is sometimes confusion of this little-known species with some very common forms of Arum italicum. This makes researching the on the Internet or even finding a seed source problematic.
Growing my newly received Arum was easy. They arrived at the end of our summer as dormant corms. I potted them up immediately and waited for them to awaken and start growing. A few weeks later, with cooling weather and some rain, green shoots emerged. These unfurled into some very handsome small leaves (no flowers, unfortunately) which gradually gave way to larger and larger leaves.
My plants do not show the intense silvery veins that are seen in some forms, but they are quite handsome. Getting to know this plant better I’ve discovered a group of international plant collectors growing this species. Since Arum pictum occurs on various western Mediterranean islands, a number of different forms seem to be in the process of diversifying further in their isolation from each other. Except now these enthusiasts are crossing and selecting forms that are even more distinct. The silver in some leaves has become pronounced, there is even a form with a reddish midrib!
The leaves are the only variation – flower color can also vary. Sometimes the dark red spathe is lighter, or even shaded from pale to deep burgundy. ‘White-spathed’ forms are not uncommon (usually green) and some of those forms also have a pale spadix as well.