Plantsman Magazine
by Tony Avent
Plant Delights Nursery Inc.
9241 Sauls Road
Raleigh, NC 27603
919.772.4794
Epimediums are known by several common names such as fairy wings,
bishop's hat, and my personal favorite, horny goat weed. In Asian cultures,
epimediums are used as herbal medicines to stimulate androgen hormones
and therefore enhance sexual desire, erectile dysfunction, and to provide
energy. This use was reportedly discovered after a farmer noticed goats
which grazed on epimediums became much more sexually active. It is with
mixed feelings that one passes bushels of dried epimedium roots in a
roadside market on the way to a high peak in Asia ... I'm sure they
provided much enjoyment for the indulging parties, but at great expense
to the preservation of many of these species.
It was 40+ years into my gardening life before I got involved with
epimediums, partially because I found the conflicting information made
them more confusing as a group. It was only with the assistance of
epimedium guru, Darrell Probst, that I was finally able to wrap my arms
snugly around this group that we have since embraced. Epimediums are
members of the barberry family which includes such other familiar garden
plants as mahonia (lumped by some into berberis), berberis, podophyllum
(mayapple), and vancouveria.
In the late Professor William Stearn's first epimedium monograph in 1938
(updated just before his death in 2001), only 21 species were known.
Even as late as the early 1990s only a handful of these known species
were represented in cultivation by living specimens. As we would soon
discover, far less than half of the epimedium species had even been
discovered or named.
Few genera of plants have seen such a dramatic increase in new species,
primarily thanks to the work of Mikinori Ogisu of Japan and Darrell Probst
of Massachusetts. Most of the epimedium species discovered and introduced
in the 1990s were due to the work of the tireless, Ogisu. His discoveries
include Epimedium campanulatum (1996), Epimedium chlorandrum (1997), Epimedium dolichostemon
(1993), Epimedium flavum (1995), Epimedium fangii (1995), Epimedium franchetii (1996),
Epimedium ilicifolium (1998), Epimedium latisepalum (1993), Epimedium ogisui (1993),
Epimedium mikinorii (1998), Epimedium rhizomatosum (1998), and previously named species
that were not in cultivation such as Epimedium brevicornu, Epimedium ecalcaratum (1991),
Epimedium fargesii, Epimedium lishihchenii (1997), Epimedium pauciflorum, and Epimedium platypetalum.
Probst's introductions include Epimedium brachyrrhizum (1997), Epimedium dewuense (2003),
Epimedium epsteinii (1997), Epimedium myrianthum (1998), and the previously described
Epimedium sutchuenense which he introduced to cultivation. Many yet to be
published species from his work are in the pipeline.
As of 2008, our collection had swelled to 49 of the currently named 54
species, along with most of the distinct hybrids. Epimediums are quite
the promiscuous bunch, with bees creating both garden hybrids and well as
natural hybrids in the wild. While most epimediums make great garden
plants, there are a few that offer little for gardeners, and these will
not be discussed here. For the purpose of this article, I'm grouping my
descriptions based on the plant morphology ... plant characteristics that
are easily observable, especially flowers.
Epimediums spread via a woody rhizome, located just below the soil surface.
Just like bamboos, there are fast spreaders (leptomorphs), and slow
spreaders that appear to form a tight clump (pachymorphs). In the garden
and nursery, epimediums can be divided, which is best done after flowering
has finished. One of the most important tricks I learned from Darrell
Probst is to always leave two-thirds of the foliage on the newly divided
plants to encourage them to form new roots. The tight clumping
pachymorphs will be the most challenging to divide, hence the higher
price these usually demand. If you decide to try dividing them, get a
pair of bonsai scissors. Roots on divisions should be cut back to 4-5"
long. Epimediums can be grown from seed, but you'll need to have a keen
eye since the seed usually mature about 45 days after pollination (Probst).
I tried for years to gather seed, which must be sown fresh, with no luck
and now I just allow the seed to fall into a well prepared seed bed, where
it will germinate the following spring. If you're lucky enough to gather
the seed, they will require 60 days below 40 degrees F for germination.
We have been able to flower about 10% of one year old seedlings with the
rest flowering the second year. Since most epimediums are self-sterile,
a lot of your offspring will be hybrids, creating a myriad of possibilities
where many different species are grown nearby.
In gardening circles, epimediums are known as great plants for dry shade,
but in the wild, most grow in very moist soils, with many being found near
woodland waterfalls. While epimediums will indeed grow in dry shade,
they fare much better in part sun to light shade with a rich, organic,
moisture-retentive soil. As with all plants, stay away from salt-based
fertilizers which can burn epimediums when used in excess. Plants such as
Epimedium x rubrum, Epimedium x warleyense, Epimedium x perralchicum, Epimedium pinnatum ssp. colchicum,
and Epimedium x versicolor seem to be particularly durable in very dry sites.
Most epimediums are native to alkaline soils, so we recommend a soil with
a pH between 6.2 and 6.5 that allows us to grow all species well.
According to Dan Hinkley (Pacific Horticulture, 1997), the cultivars of
Epimedium grandiflorum do not fare well in alkaline soils.
Most epimediums are spring flowering, with a few species such as
Epimedium rhizomatosum and Epimedium davidii continuing sporadically through the summer.
I have categorized them into flowering times in the chart (Chart #1) below
with some beginning as early as early March (NC- Zone 7b) and other not
starting before late April. In areas subject to late spring frosts, the
flowering spikes of many of the early flowering epimediums will need to be
protected if temperatures drop below the mid-20s F.
Some epimediums have evergreen foliage, while others are completely deciduous.
As a rule, the deciduous species are more winter hardy than those that retain
their foliage. When planting them in the garden, keep in mind that just
because the foliage is evergreen doesn't mean it will look great throughout
the winter. For us, severely cold winters can damage evergreen foliage
that in some mild years may look fine. Most gardeners trim any remaining
damaged foliage in mid-late February, before the new flower spikes begin
to emerge. While many epimediums are grown primarily for their flowers,
several of the newer species and hybrids are worth growing for their lovely
foliage. Epimedium wushanense has superb mahonia-like leaves, while
Epimedium acuminatum and Epimedium x omeiense are a couple of species with
wonderful leaf mottling. Some selections of Epimedium x youngianum emerge
purple or with a red border, as does Epimedium grandiflorum v. higoense. The
leaves of Epimedium x versicolor are a kaleidoscope of colors as they emerge.
Below, I have categorized species by their plant form and flower types in
order to help you select the best plants for your site.
Small Epimedium with small/medium sized flowers
If you're looking for small and dainty in the epimedium world, the
deciduous Japanese Epimedium diphyllum is for you. This cute garden
plant has been in cultivation since the mid 1800s and ranges in flower
color from light pink to white. Epimedium diphyllum (Zone 5-8) is represented
in cultivation primarily by three cultivars Epimedium 'Nanum' (white flowers),
Epimedium 'Roseum' (pink flowers), and
Epimenium diphylum 'Variegatum'
(speckled leaves). The 8"tall flower spikes contain between 2 and 6 flowers
each ... certainly nothing to match the showier species. The fading flowers
are topped by a second flush of spring foliage. I would consider
Epimedium diphyllum to be a clumping species, but one which can make a 2' wide,
easily dividable clump in 7 years. Epimedium diphyllum and the evergreen
Epimedium sempervirens have naturally hybridized to produce Epimedium x setosum,
which is intermediate between both parents.
Mid-sized Epimediums and hybrid groups
Next are the most familiar group of epimediums ... mid-sized plants that
represent what most folks typically think of as epimediums. Plants in
this group average around 18" tall x 18" wide and are composed of several
species and hybrid groups. From smallest to largest, they include
E. sempervirens, E. x youngianum (E. diphyllum x E. grandiflorum),
E. grandiflorum, E. koreanum, and a series of interspecific hybrids.
Plantsman Darrell Probst has interesting theories on these confusing
groups and their origin that he will hopefully publish one day.
Epimedium sempervirens (Zone 5-8) is a similar Japanese species to
E. diphyllum, except for having evergreen (from Zone 7 south) foliage,
larger flowers and about 1/3 larger plant size. E. sempervirens produces
flower stalks reaching 12-15" tall with 6-10 flowers each, also in colors
ranging from white to lavender. Epimedium sempervirens is usually a tight
clumping species, although some forms can spread a bit. Another trait of
E. sempervirens is the new leaves often emerge with a lovely red flush.
Epimedium sempervirens is represented in the trade by Epimedium 'Candy Hearts'
(red edged leaves and pale lavender), Epimedium 'Cherry Hearts' (red edged
leaves and white flowers), Epimedium 'Mars' (red-purple flowers),
Epimedium 'Okuda's White' (white flowers), and Epimedium 'Violet Queen' (red-flushed
foliage and light lavender flowers). The major drawback to E. sempervirens
is the tendency of the second spring flush of foliage to obscure the
flowers.
Epimedium x youngianum represents a large group of hybrids between
E. diphyllum and E. grandiflorum. A few forms are tardily deciduous,
indicating that some hybrids attributed to this group may not belong here.
E. x youngianum is represented by a large number of hybrids in the
trade including, Epimedium 'Baby Doll Pink' (small clump with small pale pink
flowers),
Epimedium x youngianum 'Be My Valentine'
(very floriferous clump with dark pink sepals with a white cup),
Epimedium 'Beni-kujaku' (light lavender flowers), Epimedium 'Capella' (pink sepals
and white spurs), Epimedium 'Fairy Dust' (small light pink flowers), Epimedium 'Grape Fizz'
(small light lavender flowers), Epimedium 'Liliputian' (very dwarf white with
nice white flowers), Epimedium 'Milk Chocolate' (chocolate mottled leaves and
white flowers), Epimedium 'Milky Way' (white), Epimedium 'Murasaki Shikibu' (purple
sepals and white spurs), Epimedium 'Pink Star' (pale pink, nearly white),
Epimedium 'Purple Heart' (bronze leaves and white flowers), Epimedium 'Royal Flush'
(reddish bronze foliage and light pink lavender flowers), Epimedium 'Ruby Tuesday'
(pink spurs with a violet cup),
Epimedium x youngianum 'Tamabotan'
(purple foliage and light lavender flowers)', Epimedium 'White Cloud' (small
clump with white flowers), and Epimedium 'White Star' (white flowers). We
find each of these to be dramatic improvements over Epimedium x youngianum 'Niveum'
and Epimedium x youngianum 'Roseum'. Some clones of E. x youngianum also have a
second flush of foliage that obscures the flowers, but the problem isn't
nearly as prevalent as in E. sempervirens or E. diphyllum. As expected,
E. x youngianum is usually intermediate between the spreading clumps of
E. diphyllum and the tight clumps of E. grandiflorum.
Epimedium grandiflorum (Zone 4-8) is a winter deciduous Japanese species
that represents the majority of the epimedium cultivars in commercial trade.
Like E. sempervirens, most forms are tight clumpers, although a few may have
longer rhizomes. Many of the earlier selections of E. grandiflorum have
large flowers produced among or just slightly atop the foliage, usually
obscured by the second spring flush. Selections of E. grandiflorum in
the trade include
Epimedium grandiflorum var. higoense 'Bandit'
(dwarf plant with red-edged leaves and white flowers),
Epimedium grandiflorum 'Benedict's Violet'
(lavender flowers),
Epimedium grandiflorum var. violaceum 'Bronze Maid'
(chocolate foliage and light lavender flowers),
Epimedium 'Cranberry Sparkle' (chocolate new leaves and cranberry red flowers),
Epimedium grandiflorum 'Dark Beauty'
(chocolate leaves and white cup and spurs/purple outer sepals),
Epimedium 'Lavender Lady' (dark purple buds opening to light lavender flowers) ,
Epimedium 'Lilafee' (bronze mottled foliage and lavender purple flowers),
Epimedium grandiflorum 'Pierre's Purple'
(dark purple flowers),
Epimedium grandiflorum 'Princess Susan;
(white cups and spurs with purple outer sepals),
Epimedium 'Purple Prince' (dark purple cup with light lavender spurs),
Epimedium grandiflorum 'Red Queen'
Epimedium 'Red Queen' (carmine red),
Epimedium 'Saxton's Purple' (light lavender flowers),
Epimedium 'Silver Queen' (white flowers),
Epimedium 'Spring Wedding' (red edged leaves, pale lavender flowers),
Epimedium 'Swallowtail' (red edged leaves and light lavender flowers),
Epimedium grandiflorum 'Tama-no-gempei'
(white cups and spurs, purple outer sepals),
Epimedium 'Waterfall' (rose purple flower with white spurs),
Epimedium 'Yellow Princess' (light yellow flowers), and
Epimedium grandiflorum 'Yubae'
(purple foliage, cranberry flowers).
With the exception of E. grandiflorum 'Swallowtail', the other
E. grandiflorum selections don't pick up their nice leaf coloration
until after flowering.
Epimedium koreanum (Zone 3-7) was long considered a subspecies of
E. grandiflorum, but was finally split out as a species on it's own.
As the name indicates, it is found in Korea and northern Japan.
While most E. grandiflorum outside of Northern Japan where
E. grandiflorum var. flavescens resides,
E. grandiflorum has flowers of white to purple, while
E. koreanum has yellow flowers. Also, the deciduous
E. koreanum spreads 6-12" per year via rhizomes compared to the
typically clumping E. grandiflorum. In the trade, E. koreanum is
represented by two selections,
Epimedium koreanum 'Harold Epstein'
(light yellow flowers on red stems), and Epimedium 'La Rocaille' (creamy flowers).
Epimedium x rubrum (Zone 4-8) is a name used for a group of semi-evergreen
hybrids between E. alpinum and probably E. sempervirens
(Probst - Garden Vision catalog 1997). E. x rubrum is most prized for
its leaves, which emerge with a stunning reddish margin. The short spikes
of pinkish red flowers can be obscured if the old foliage is not removed
before flowering. The unnamed clone in the trade is widespread thanks to
the fact that it spreads well via rhizomes. A much more vigorous clone
named Epimedium 'Sweetheart' was introduced by Darrell Probst. As with
E. grandiflorum, the attractive red leaf edges don't occur until flowering
is finished.
Epimedium x versicolor (Zone 5-8) is the name for a group of hybrids
between the deciduous Japanese E. grandiflorum and the European native
evergreen Epimedium pinnatum first raised in the Ghent, Belgium Botanic Garden
in the mid 1800s. These hybrids are known for their stunning new foliage,
which is chocolate, highlighted by green veins. From Zone 7 south,
the foliage remains evergreen, but becomes deciduous as you head further
north. The well-spreading Epimedium x versicolor is represented in the trade by
Epimedium 'Sulphureum' (evergreen, new foliage brown with green veins, light
yellow outer sepals, light yellow spur and cup),
Epimedium 'Neosulphureum' (tan new evergreen foliage and creamy sepals with
a yellow cup), and
Epimedium 'Versicolor' (deciduous, stunning netted new foliage of dark cinnamon,
peach sepals with a yellow cup).
My favorite of the group is
Epimedium x versicolor 'Cherry Tart'
(cinnamon foliage and light pink sepals, dark pink spurs, and a yellow-tip
cup.
Epimediums with short flower spikes and large spider-type flowers
The next group are evergreen epimediums that have large flowers in pink
to white, but are borne on short flower stalks. Epimedium brachyrrhizum,
first described from China in 1997 is similar to another species,
Epimedium leptorrhizum (Zone 5-8) that has been known since 1938. Both have
spreading rhizomes with Epimedium brachyrrhizum possessing a thicker rhizome,
spreading considerably slower. For us E. leptorrhizum never exceeds
6" in height, while E. brachyrrhizum typically reaches 1' tall.
Both evergreen species are topped in early spring with very short flower
spikes of 8-12 flowers ranging from pink to lavender, and occasionally
white. E. brachyrrhizum (Zone 5-8) is represented in the trade by two
hard to find cultivars Epimedium 'Elfin Magic', and soon, the white flowered
PDN selection Epimedium 'Little Angels'. The foliage of E. brachyrrhizum turns
a nice shade of lavender in the winter. Epimedium ogisui(1993) (Zone 6-9) is
a similar spreading evergreen species with near horizontal spikes of
large white flowers. The Chinese Epimedium epsteinii (Zone 5b-8),
also named in 1997, is a similar evergreen species with short, but
spreading rhizomes and short flowers spikes, sporting up to 12 large
bicolored inflorescences of purple cups and spurs, backed by a white
outer sepal. Plants in this group make superb groundcovers, often with
attractive red mottled foliage.
Some of the most showy epimediums are those with large flowers on long
spikes. The evergreen Epimedium acuminatum (Zone 5-8) from limestone
cliffs in the Southern Chinese provinces of Yunnan and Sichuan leads this
list along with its hybrid, Epimedium x omeiense (acuminatum x fangii).
E. x omeiense is fairly new to cultivation, first flowering in cultivation
in 1982 (W. Stearn 2002). In our studies, the primary easily visible
difference is that Epimedium acuminatum has smaller, narrower leaves and is
shorter in stature, 12" tall for E. acuminatum, compared to 24" tall
for E. x omeiense. E. acuminatum flowers with 18" long arching spikes,
each adorned with up to 50 large flowers composed of long dark purple spurs,
highlighted by pale lavender inner sepals. The flowers are so large,
the spikes can become quite heavy, so much that their tips nearly touch
the ground. For this reason, I recommend both E. acuminatum and
E. x omeiense be planted atop a berm, so the flowers can be better enjoyed.
Both E. acuminatum and E. x omeiense are prized for their long-pointed and
wonderfully mahogany mottled leaves. Compared to the tight clumping
species, this is a reasonably good spreading species. Heronswood's
E. acuminatum 'Ruby Star' (white sepals, lavender spurs, and a purple cup),
and Darrell Probst's E. acuminatum 'Night Mistress' (pink spurs, purple spurs,
and a purple cup) are the two easiest to find clones on the market.
Mikinori Ogisu=s wild collected clone of E. x omeiense released as
Epimedium 'Stormcloud', Dan Hinkley's 'Myriad Years' (white sepals, light
lavender spurs and a purple cup), and the Japanese 'Akane' are the easiest
to find in the market.
Epimediums with yellow spider-type flowers
There are a number of evergreen Chinese species with large cream to
yellow flowers including Epimedium davidii, Epimedium fangii,
Epimedium flavum, Epimedium hunanense, Epimedium franchetii,
Epimedium lishihchenii, Epimedium rhizomatosum, Epimedium membranaceum,
Epimedium chlorandrum, and Epimedium wushanense. I would consider all
of these to make very showy garden specimens.
Although first discovered on limestone cliffs in China around 1869, the
garden worthy Epimedium davidii (Zone 5-8) wasn't introduced to cultivation
until 1985. There are both tight clumping and slowly spreading forms of
E. davidii, both of which hold their spikes of up to 2 dozen curved
yellow-spurred flowers above the small spiny green foliage for good
visibility. Because new buds that form along the rhizomes and the leaf
axils re-flower (Probst, American Nurseryman, 1998), it produces new
flowers for us throughout the summer. E. davidii is a superb garden
plant deserving more widespread recognition, although it is not a species
that performs well in dry locations. The Chinese Epimedium fangii (1995)
(Zone 5-8), E. flavum (1995) (Zone 5-8), and E. hunanense (1931)(Zone 5b-8)
are similar evergreen species with short flower stalks of bright yellow
flowers. These are still little known in cultivation. E. fangii is the
fastest spreading of these species, followed by the vigorous E. hunanense
and then the dwarf E. flavum. The flowers in this group are much smalller
than the rest of the yellow spider group.
Epimedium franchetii (1996) (Zone 4-8) and the similar Epimedium
lishihchenii (1997) (Zone 4-8) are slowly spreading evergreen species,
also recently discovered in China. Both of these species are similar in
growth and form to Epimedium acuminatum and Epimedium x omeiense, but
with up to 2 dozen large yellow flowers with recurved spurs, held
horizontally on sturdy 2' long flower stalks. Both species can produce
foliage that emerges with an attractive bronze hue. Although some folks
argue that these represent a single species, we find that all of our
clones of E. lishihchenii have much larger foliage than E. franchetii.
I feel that the cultivar E. franchetii 'Brimstone Butterfly' actually
belongs to E. lishihchenii. Epimedium chlorandrum (1997) (Zone 5-8)
is a similar slowly-spreading species native to Sichuan and also
resembles E. acuminatum, but the flowers are creamy yellow on 2' long
arching spikes.
Another group of yellow spider-flowered epimediums include
Epimedium rhizomatosum, Epimedium membranaceum, and Epimedium ilicifolium.
For us the Chinese Epimedium rhizomatosum (Zone 5-8) flowers longer than
any other species, often reblooming throughout the summer. As the name
would indicate, E. rhizomatosum, named in 1998, spreads via long rhizomes,
as compared to the shorter rhizomes of the similar looking
E. membranaceum (1922). E. rhizomatosum is adorned with short 15" long
flower stems of large-spurred yellow flowers. Epimedium membranaceum
(Zone 5-8) is a similar species with up to 30 large-spurred yellow flowers
on 2' long stems. E. membranaceum is a superb garden specimen that starts
flowering just as Epimedium franchetii ends and continues all summer,
thereby extended the flowering season. The third and smallest of the group
is Epimedium ilicifolium, a smaller growing (1' tall x 2' wide in 3 years)
plant, composed of narrow, spiny green leaves. Despite its small stature,
E. ilicifolium is one of the most floriferous of the group with light
yellow flowers that are tightly packed along the flower spike as compared
to the wide spacing of E. rhizomatosum and E. membranaceum.
As best I can determine, the slowly spreading Epimedium wushanense
(Zone 5-8), although named in 1975, wasn't sold before 2000.
My prediction is that it won't be long before this becomes one of the
most popular garden species. The long, spiny evergreen leaves (nicely
mottled in some clones) up to 8" long come through the winter in great
shape (NC), and serve as a nice background for the spikes of up to 100
long-spurred creamy-yellow flowers. The entire flowering spike can reach
nearly 3' in height. The flowers are bunched closely together and held
just above horizontal on a very sturdy spike.
Epimediums with small yellow bell-shaped spurless flowers
For something a little more dainty, there are yellow-flowered species
without the long spurs of the group above. Epimedium platypetalum (1922)
(Zone 5-7) is a cute semi-evergreen Chinese species with spreading
rhizomes and small yellow spurless bell-shaped flowers along 1' tall
flowering stems. Two other little known, but similar Chinese species
with compact rhizomes are Epimedium ecalcaratum (1991) (Zone 5-7) and
the clump-forming evergreen Epimedium campanulatum (1996) (Zone 4-7a),
topped in spring with 2' flower stalks of small yellow bells.
Epimediums with tiny white flowers
You'll never hear this next group decried as showy, but I would not be
without these in my garden for their understated charm. The clumping,
evergreen Epimedium sagitatum (1877) (Zone 5-8) is one of many Chinese
species with tiny flowers, but the feature to recommend is the attractive
cinnamon colored leaves as it emerges. The only cultivar of E. sagitatum
in the trade is Epimedium 'Warlord', a plant that is worth growing for
it's exceptional red and tan flushed new foliage. Epimedium myrianthum
(1998) (Zone 5-8) is similar to E. sagittatum, except the former usually
has red tinted foliage, while the latter is often mottled and E. myrianthum
has a much larger number (up to 150) of tiny flowers. E. myrianthum,
which can often rebloom in summer, is represented in the trade by the
stunning foliaged Darrell Probst introduction, Epimedium 'Mottled Madness'.
Epimedium pubescens (1877) (Zone 6-8) is a similar evergreen species
with slightly larger flowers. Unlike the previous two, E. pubescens comes
in both a clumping and a creeping form. Epimedium stellatum is relatively
new, being introduced to cultivation in 1983 and only named in 1993.
E. stellatum (Zone 5-8) is similar to the above three species, but with
even larger flowers on a 20" tall stalk that gives it considerably garden
value. The most common cultivar of E. stellulatum in the trade is
Roy Lancaster's dwarf 1' tall 1983 Chinese collection, 'Wudang Star' and
a taller 20" tall clone known simply as "long leaf form". Other species
in this group, which are still relatively rare include the Chinese
Epimedium truncatum (1990) (Zone 5-8), and Epimedium baieali-guizhouense
(1993) (Zone 5-8), each with tiny white flowers.
Epimediums with Dodecatheon-like flowers
Several other favorites that don't resemble any of the aforementioned
species are the clumping evergreen species Epimedium fargesii (1894)
(Zone 5-8), Epimedium dewuense (2003) and the slowly spreading evergreen
Epimedium dolichostemon (1988)(Zone 5-8). In flower, these more closely
resembles a dodecatheon (shooting star). I find E. fargesii to be of
the most elegant, understated of all the fairy wings ... unfortunately,
the lack of commercial demand will probably keep it rare. Epimedium
fargesii is represented by the cultivars Epimedium 'Pink Constellation',
Epimedium 'Pink Treasure', and Epimedium 'Star Shower'. Epimedium
dolichostemon which has wider spurs is also prized for its wonderfully
mottled foliage. Epimedium dewuense is the smallest of the three with
flowers that resemble a small Epimedium fargesii.
Other Epimedium Species and Hybrid Groups
Other than the previously mentioned species and groups, there are a couple
of others which are fairly widespread in commercial production.
The European Epimedium pinnatum ssp. colchicum (1903) (Zone 5-8) is a
lovely evergreen species, best known in the trade by the US National
Arboretum collection from near the Black Sea and later named
Epimedium pinnatum ssp. Colchium 'Thunderbolt'
In cold weather, the foliage darkens to nearly black with a few green veins.
Epimedium x warleyense is a hybrid of Epimedium alpinum and Epimedium pinnatum
ssp. colchicum. This is one of the few true orange epimediums. Commonly
available cultivars from this cross include Epimedium 'Ellen Willmott', and
Epimedium x warleyense 'Orangekonigin'.
Epimedium perralderianum (1862) (Zone 5-8) is the only species native to
Africa ... Algeria, in fact. The 1' tall stalk, held above the foliage is
adorned with up to two dozen large bright yellow flowers. A similar
looking hybrid to the parent derived from crossing E. perralderianum with
the closely related Epimedium pinnatum ssp. colchicum is
Epimedium x perralchicum. This cross, also with long spreading rhizomes
as it parents, is represented in the trade by Epimedium 'Frohnleiten'
(reddish spring foliage with green veins and only 8" tall, yellow flowers),
and Epimedium 'Wisley'.
Epimedium Hybrids
Despite all of the fabulous species and species selections, some of the
most exciting new epimediums are coming from interspecific crosses. I
thought I'd share a few of my favorites.
Epimedium 'Amber Queen' PP 17,197
is a cross of Epimedium 'Caramel' x Epimedium flavum. This amazing
hybrid is topped with large floral sprays of large golden flowers.
Also from Robin White's breeding program in the UK is
Epimedium 'Pink Elf' PP 17,228. This
floriferous hybrid comes thanks to Epimedium pubescens with the other
parent in question ... reportedly Epimedium leptorrhizum, but I'm betting
on Epimedium grandiflorum. This is the very first epimediums to flower for
us, often starting to bud by early March. The numerous flower stalks create
a cloud-like effect of small flesh-colored flowers.
There are a number of other hybrids of unknown parentage. Some of my
favorites including the Japanese hybrid
Epimedium 'Yohiki',
a later selection with long-spurred white flowers, which have white cups
and hot pink sepals.
Epimedium 'Spritzer'
is a wonderful Epimedium membranaceum hybrid from Darrell Probst with
heavily liver-speckled, spiny-edged leaves, topped starting in late March
with tall spikes of large yellow flowers with contrasting coral sepals.
Another one of my favorites of Darrell's hybrids is
Epimedium 'Domino' ... mid-March flowering
vigorous 3' wide specimen with nicely mottled leaves, topped with 2' tall
burgundy flower spikes that have huge numbers of large white flowers,
highlighted by pink cups. Two others that should soon become more widely
available are Robin White's Epimedium 'William Stearn' (long pink spurs and
raspberry cups) and Darrell Probst's E. 'Pink Champagne' (red mottled
foliage and flowers of long light pink spurs and raspberry cups). These
are just a sample of the wonderful hybrids that have just begun to hit the
market with more on the way including many from our work here at PDN.
I hope you find this group as enjoyable as I have and hope your interest in
epimediums has been "spurred" to new heights. Again, a final thanks to
Darrell Probst, without whom this would not have been possible and without
whom many of these great epimediums would never have made it into commerce.
Chart 1 - Epimedium Relative Flowering Times
*Flowering times are average in Zone 7b Raleigh, NC (average winter temperatures -15 degrees C (5F) and will be later in colder climates and earlier in others.
- Early March - Mid March
- E. pubescens - ends late April
- Mid March - Late March
- E. brachyrrhizum - ends mid-April
- E. chlorandrum - ends late April
- E. epsteinii - ends mid- April
- E. fargesii - ends mid-April
- E. franchetii - ends mid-April
- E. sagitatum - ends early April
- E. sempervirens - ends mid April
- E. stellatum - ends early May
- E. truncatum - ends early May
- Late March - Early April
- E. acuminatum - ends early May
- E. davidii - ends May-July
- E. dolichostemon - ends mid April
- E. grandiflorum - ends mid April
- E. leptorrhizum - ends mid- April
- E. lishihchenii - ends mid-April
- E. myrianthum - ends mid-April
- E. ogisui - ends late April
- E. pauciflorum - ends mid-April
- E. rhizomatosum - ends mid-May
- E. x rubrum - ends mid-April
- E. x setosum - ends mid April
- E. x versicolor - ends mid April
- E. x youngianum - ends mid April
- Early April - Mid April
- E. baieli-guizhouense - ends late May
- E. brevicornu - ends mid-May
- E. x cantabrigiense - ends early May
- E. diphyllum - ends late May
- E. grandiflorum v. higoense
- E. hunanense - ends late April
- E. ilicifolium - ends late April
- E. x omeiense - ends early May
- E. x perralchicum - ends late April
- E. pubigerum - ends late April
- E. x sasaki - ends late April
- E. wushanense - ends late April
- Mid April - Early May
- E. dewuense - ends early May
- E. membranaceum - ends August
- E. platypetalum - ends early May
- E. shuichengense - ends mid-May