The Genus Edgeworthia
Edgeworthia
There is one thing I know
for certain about Edgeworthia. No one seems to know what species
they have and few seem to know if more than one species actually
exists. I include myself amongst the taxonomically
challenged and amongst those guilty of propelling improper
nomenclature through my writing and speaking.
We grew what we called Edgeworthia papyrifera for many years at
Heronswood, having received our first plant from J.C. Raulston under
this name. It thrived in our woodland, each year setting
enormous quantities of silvery buttons in autumn that would open to
yellow, fragrant clusters of flowers in late January. We
twice dug a single specimen for use in Flower and Garden show
displays in Seattle and it sailed through both insults without harm.
Life seemed good.
Our plant formed a small
rounded shrub to 5’ with slender rubbery textured stems and bright
green deciduous leaves to 3” in length. There was a slight but
not overwhelming fragrance. It grew well in two locations of the
garden; both in shade as well as bright filtered light, in well drained
soils.
Things became more interesting when a
Canadian nursery began selling another clone ( or species?) of
Edgeworthia that appeared miles apart in appearance, under the name of
E. chyrsantha. Good enough. Stout in growth, the
leaves and inflorescenes were double the size of our plant, the flowers
much more fragrant. Unfortunately, at about the same time, the
RHS Plant Finder listed E. papyrifera as a synonym of E. chyrsanthum,
essentially leaving one of plants quite nameless. Which one?
In my experience thus far, the original clone we received from
Dr. Raulston is the best clone for cultivation in the greater Puget
Sound, while the more robust form seems to appreciate the heat (and
humidity) of the Southeastern states as well as Portland and
surrounding environs.
I have seen
Edgeworthias in the wild on numerous occasions. In E. Nepal in
1995 and again in 2003, we found them common, and encountered on
occasion local villagers making paper from its bark. In Sichuan
Province in 2003 and 2004, we hiked through thickets of Edgeworthia and
was, at that time, afforded the opportunity to collect its fruit.
Those collections were sold at Heronswood under a DJHS designation in
2006 under the name of Edgeworthia gardneri These, from my
limited perspective, seemed to represent the ‘taxa’ we had received
under the name of E. chrysantha though seemed to fit the botanical
description of the name we provided.
The only
time I have seen a plant resembling our original Edgeworthia
‘papyrifera’ has been under cultivation in Japan. In particular,
the red/orange flowered forms frequently encountered in gardens in the
Tokyo area seem to be identical in appearance but for the flower color.
In the Thymelaeaceae, this deciduous ‘Daphne’ would seem to
possess a certain degree of hardiness however that does not seem to be
the case. Though there are reports of some survival in protected
sites in the Philadelphia area, I do not believe one could expect
consistent flowering in zones 6 or lower.
There is another thing I know for certain about Edgeworthia.
Despite its taxonomic confusion, I would not be without it in my
garden. It is representative of the bounty of plants that bring
interest to the garden in the temperate winter garden as well as
accentuating exactly how much there remains to learn of the plant
world. That in itself is exciting.
If anyone reading this can illuminate me as to recent taxonomic
work on this genus, or personal musings on their experience with this
genus, I would greatly appreciate hearing from you.
info@danieljhinkley.com
DJH
This response from Tony Avent adds some additional light to the befuddlement of this genus.
Dan:
Perhaps I can shed more confusion about edgeworthia. The original plant that JC grew was a clone that Don Jacobs selected called E. papyrifera 'Eco Yaku'. We planted this clone all around the NC State Fairgrounds. The flowers and leaves were fairly small and I could detect no fragrance. He later acquired E. chrysantha, probably from Piroche. I got my original from Gossler via Piroche and it had the larger leaves and larger fragrant flowers. Ted Stephens later acquired seed of E. chrysantha and grew out many hundred to maturity. The seed variation was amazing, primarily in flower size as well as the leaves. Even looking at several hundred flowering plants, none were remotely close to the plant I know as E. papyrifera. All of Ted's seedlings were fragrant, compared to none of the E. papyrifera that I have seen. All of the E. papyrifera clones that we have grown are killed, or nearly so at temps below 5 degrees F., while E. chrysantha has dipped to 0 F with no damage several times. It is possible that E. chrysantha is a tetraploid population of E. papyrifera, but short of that, it sure looks like a good species. The only plant that I have seen as E. gardenii is the evergreen plant that Sean Hogan grows...totally different from the other two species. I hope this confuses you more.
--
Tony Avent