Looking lovely in the gardens today is the incredible Epimedium ‘Pink Champagne’. This 2007 Darrell Probst introduction still remains one of the finest fairy wing cultivars ever introduced. Our plant below is growing where it receives a couple of hours of mid-day sun. A mature clump will reach 2′ tall x 3′ wide. Winter hardiness is Zone 5a-8b.
Tag Archives: evergreen groundcover
A Tweet from the Cordial Canary
Ajuga ‘Cordial Canary’ is one of the new generations of well-behaved bugleweed selections, this from the work of Chris Hansen. It looks pretty amazing for mid-March at JLBG. We love colorful groundcovers that play nice with their surroundings. Zone 4a-9b.
Palmer’s Winter-blooming Sedum
Sedum palmeri ‘Mendoza’ is looking superb in the garden in late winter. This northern Mexico native is one of our favorite species, flowering far earlier in the year than any of the other sedum species we grow. We had tried Sedum palmeri prior to to growing this clone, and never succeeded in getting it to survive our winters.
In 2002, we were eating lunch at a ski lodge near the border with Argentina and Chile, when I spotted this compact form growing in a flower bed. We have no idea how a plant from Northern Mexico got so far from its’ home, but we’re glad it did. This patch in the garden was grown from a single cutting we legally brought home from the trip. We subsequently named this after the nearby town of Mendoza, and introduced it through Plant Delights in 2013. Zone 7b-10b, at least.
Carpet’s of White
Here are a couple of groundcovers that are looking nice in the garden in early March. The first is the Western US native, Cerastium beeringianum (Western Snow in Summer), which is a close relative of the Italian Cerastium tomentosum. We selected this form from seed we grew, originally purchased from a native plant nursery as the US native, Arenaria stricta–oops! Both genera are at least members of the dianthus family, Carophyllaceae.
We’re still pretty excited, despite the misname, since this is an alpine species that typically grows above 10,000′ elevation. We’ve added the name ‘Southern Snowstorm’ to this exceptional clone.
Below is the Balkan native, Arabis procurrens. This member of the Brassicaceae family makes a superb groundcover. Our 5 year old, well-behaved, evergreen clump pictured below is almost 4′ wide.
Not so drab Draba
We love the late winter flowering Drabas, which thrive in our dry crevice garden. Below is the miniature Draba hispanica, which has been in flower since late February. This Spanish species likes to grow in dry limestone cracks, such as the one we provided here. Unless you’re an avid rock gardener, you may not realize that draba is actually in the cabbage family, Brassicaceae. Once the flowers finish, you’re left with a fuzzy evergreen bun of foliage for the rest of the season. Zone 5a-8a, at least.
Looking fabulous in the garden now is Veronica umbrosa ‘Georgia Blue’. We’ve grown this amazing groundcover in the garden since 1990, and find it as great now as it was 33 years ago. This superb introduction was originally collected in the wild in Georgia (the country, not the state) by England’s legendary plantsman, Roy Lancaster in 1979. In 30+ years of growing it, its never misbehaved or thrown a single seedling. Flowering time for us is usually from mid February through March, so it can be used as a background for spring bulbs.
Splurge with Allegheny Spurge
Flowering in the garden now is the wonderful US native Pachysandra procumbens (Allegheny spurge). Native from Indiana south to the gulf coast, our selection, Pachysandra ‘Angola’ comes from the woods near that well-know Louisiana prison. This stunning evergreen, variegated, slow-spreading, woodland groundcover, is quite different from its better known and much faster spreading Asian cousin, Pachysandra terminalis. The flowers are also sweetly fragrant, what more could you want? Hardiness is Zone 5a-9b.
Distilled Spirits of Winter
Our plants of the shrubby Distyllum myricoides has been in stunning flower for the last few weeks. This fascinating evergreen shrub, mostly native to China, is in the same family, Hamamelidaceae, as its’ better-known cousins, Hamamelis (witch hazel) and Fothergilla (witch alder).
Due to the breeding efforts of Dr. Michael Dirr, distyllum has actually begun to show up in box stores…something that was unthinkable two decades earlier. We love it for the evergreen foliage, but what really excites us is the amazing winter floral show as you can see below.
Stick out your tongue fern and say, Ah-ha
We’re several years into an experiment to see how well the epiphytic (grow mostly on trees) tongue ferns of the genus Pyrrosia fare in hanging, moss-lined baskets when left outdoors all year. This is our coldest winter to date since the test began, with a low of 11 degrees F. Here is a photo of one of those baskets taken today. They were not protected in any way during the cold. We have 17 clones on trial in this manner, and some do show a bit of foliar damage, while others are untouched. We think it’s quite amazing to have evergreen hanging baskets of live plants that can remain outdoors here in Zone 7b.
Splendor in the Cracks – Urophysa
I’m betting that even the most seasoned plant collectors probably haven’t grown or even heard of Urophysa henryi. This odd generic member of the Ranunculaceae family hails from China, where it can be found only in a very few scattered populations, hanging out from cliff-side karst rock fissures in Guizhou, Sichuan, Western Hubei and into Northwestern Hunan.
Urophysa henryi is very closely related to the highly prized, but rather difficult to grow, rock garden plant, Semiquilegia adoxoides. I was particularly interested to read in a 2021 Chinese research paper, “In field observations and laboratory experiments, we found that U. rockii and U. henryi can not survive outside the karst limestone, which indicated that the karst limestone plays a significant role in their growth and development.” This is why you never send a botanist to do a horticulturist’s job!
In our garden, sans the Karst limestone, it has thrived in our rock garden, not blinking this year at 11F. The 4″ tall x 6″ wide evergreen clumps of columbine-like foliage are topped with clusters of small, outfacing white flowers, which resemble our native Isopyrum biternatum, Like Isopyrum, Urophysa flowering starts for us in early January, and continues through March. We think these are an outstanding addition to the winter garden and are going to do our best to get these propagated to share before words gets out that they can’t be grown in cultivation.
A Lumpy Pancake
I was just admiring our specimen of the East Coast native, Thuja occidentalis ‘Concessarini’ today. I find this a fascinating plant in the garden, sadly never promoted by those who claim to extoll the virtues of native plants.
Our oldest specimen below is now 10 years old and measures 3′ tall x 6′ wide…quite a bit larger than it’s introducer claims it to be at 1′ tall x 2′ wide. If you dig deeper, you’ll see that the plant patent application shows they only measured a three year old plant, and have never bothered to update the mature size in their marketing or on their tags. It shows how little many plant introducers think of the end consumer, when they set them up for failure by promoting these fake mature sizes. Commercially, it is marketed under the fake trade name of Pancake arborvitae. That’s one seriously lumpy pancake.
This juvenile-foliage sport of Thuja ‘Linesville’ was discovered by nurseryman, Gabriel Cessarini. We think it’s pretty cool, just allow enough room in the garden. Winter hardiness is Zone 3a-8b.
Our 13 year old clump of the evergreen Japanese Asarum asperum is looking superb in the garden this week. Looks like it’s about time to divide this for the first time and start to build up stock so we can share in the future. Winter hardiness is Zone 6-9.
Casting Around Seed
We can’t imagine there are many people who grow cast iron plants from seed, but we have found the results quite fascinating. Below are a couple of our seedling which we found good enough to name. Neither has been divided yet, and are still under evaluation, but we think they have good potential.
Aspidistra ‘Bright Lights’ is a 2015 seedling from Aspidistra ‘Okame’ and has a similar variegation pattern, although it has more white banding than its parent.
Aspidistra ‘Illumination’ is a 2016 seedling of Aspidistra ‘Sekko Kan’, and inherited the white tips from its mama, but has also pickup up more streaking that wasn’t present in the preceding generation, so perhaps it outcrossed to a nearby streaked parent. If you’re interested in trying this yourself, the seed are found in a 1-2″ wide green ball at the base of the plant now. The seed should be mature in the next 4-6 weeks.
In 2014, Plant Delights introduced this amazing, wild collected mondo grass, which we think is one of the coolest ophiopgons we’ve ever grown. This Darrell Probst collection from China has formed a 20″ tall x 4′ wide mound of foliage. This image was taken in the garden this week after our 11 degree F freeze, and is looking absolutely fabulous. Although it keys out to Ophiopogon japonicus, it doesn’t phenotypically (what it looks like) that species. We’re pretty sure it represents a new undescribed species.
We love the texture, both in the woodland garden and in half day full sun. Although it’s winter hardy throughout Zone 6, it was one of the worst selling plants we ever offered. Sometimes we just want to throw our hands up trying to figure out why people don’t purchase some of these amazing plants.
At the Coast with Holly
The typical holly fern, Cyrtomium falcatum, is considered fairly reliable in Zone 7b, but no further north. The oddball is the coastal form, which grows on the coast of both Japan and Korea. We received the plant shown below in 2005, as Cyrtomium falcatum var. maritimum, which our taxonomy staff tells me, isn’t a valid name. According to Patrick and Zac, the Japanese coastal material is correctly called Cyrtomium falcatum var. littorale, but there is no mention in the literature they’ve reviewed of the same coastal form occurring off Korea.
Other than the dwarf size, which is often seen in plants that grow in harsh coastal conditions, these weather-battered denizens adapt by developing thicker leaves and a denser habit. Additionally, this form is significantly more winter hardy than the typical material of Cyrtomium falcatum seen in the trade. We’ve always listed this dwarf form as a Zone 7a plant, but we wouldn’t be surprised at all if it’s also hardy in Zone 6. If you’ve been adventurous enough to try it, we’d love to hear from you. Our mature clumps below, photographed over Christmas, are now 8″ tall x 18″ wide.
Holiday Cast Offs
During the holidays, house plants often get relegated to dark, unattended corners, but some house plants make great holiday decorations without any special seasonal input. One of those is the Taiwan native cast iron plant, Aspidistra attenuata. Here are 3 clones in our collection, all photographed this year on Christmas day. In order, they are Aspidistra attenuata ‘Alishan Broad’, ‘Dungpu Dazzler’, and ‘Taiwan Treasure’. These are but a few of the amazing cast iron plant species and cultivars that are sadly ignored commercially. We think they’re pretty cool.
This is a very good year for the annual winter fruit show on Rohdea japonica (sacred lily). The attractive berries remain until early March, when they begin to drop. Although seed from these cultivars do not come true, you’ll always end up with an interesting variety of offspring.
Dry-opteris on a Wet, Rainy Day – New Relevations
The cold and raw weather of late autumn and winter provide the perfect opportunity to sit down with the dissecting scope and put our ferns through the identification mill. Often gardens and nurseries receive a plant into their collections from an exporter or collector who has put their best guess on the identification. After many years in cultivation, we realize what we thought was the right species name for our specimens is incorrect. Today’s nasty weather provided the opportunity to examine, in detail, one of our favorite evergreen fern groups – Dryopteris section Variae.
These firm-leaved evergreens produce thick-textured, durable, medium-sized fronds of varying shape but all display a noticeably longer basioscopic pinnule (that’s fancy talk for the lowest, innermost segments of the divided leaves). All members of the section that we have grown have proven to be very adaptable to our hot, humid summers and unpredictable winters if grown in shade or partial shade in moist woodland garden conditions. The fronds tend to burn if they receive too much light. They are late risers in the spring often not producing a new flush of leaves until late spring or even early summer.
At the beginning of the day, we started with 8 accessions of Dryopteris varia, 2 accessions of Dryopteris bissetiana, 6 accessions of Dryopteris formosana, one accession of Dryopteris saxifraga and a couple of unknowns. From these numbers you would expect that the one plant we would know best would be Dryopteris varia.
Well…it turns out all the plants we had received or had identified as D. varia were actually representative of other taxa. If you’ve never tried keying ferns using The Flora of China or The Ferns and Fern Allies of Taiwan, you would have no idea just how difficult a process this is. The floras of these areas are notoriously difficult to use and often contradictory or difficult to assess using illustrations or pictures (yes even plant taxonomists google names to find images). Very quickly we became intimately familiar with the nature of the stipe and rachis scales, frond outlines, and disposition of the vestiture (yeah you think that sounds easy, right?).
We found most of our collection was actually composed of Dryopteris bissetiana, which are mostly from collectors who sent us tentatively identified wild-collected material. The majority of these were from Sichuan in China, however one very beautiful, deep green and glossy selection that is only half the size or less of the others was Tony’s collection in Korea, and has tentatively been identified as Dryopteris saxifraga. All of these are remarkable garden plants, but we are very excited to some day offer the choice dwarf from Korea which we have named ‘Cheju Dwarf.’
It was a pleasant surprise to find that our collections of Dryopteris formosana were correctly labelled, but we weren’t prepared for there to be two distinctly different looking plants represented in our garden that are the same species.
One of these is the plant that has been shared among fern enthusiasts for some time that is the typical sexually reproducing diploid. The other is an apogamous triploid that looks like a completely different species. In a diploid (like you and I) the pairs of chromosomes uncouple and one copy of each goes into making the male and female gametes.
Thus, each gamete has only one set of each chromosome (haploid) and when combined with those from the complementing sperm or egg results in another diploid. Plants sometimes have a mistake in their cells that lead to the production of gametes with twice as many chromosomes as they would normally have and when such tetraploid plants breed with a diploid the result is a gamete with 2 copies of each chromosome combining with a gamete with only one—thus triploid. In your average plant this triploid is a dead end for reproduction by seed or spore because they have an uneven base number 3—which can’t be divided into an equal number of chromosomes, so it is sterile.
This triploid avoids the curse of having an uneven number of chromosome pairs by avoiding sexual reproduction and producing spores that will result in new plants without the traditional interplay of sperm and egg on a germinated gametophyte (yes apogamy in ferns is still legal in all states and countries). We were puzzled when two very different looking ferns keyed to the same species. Everything that was in the key matched. The bullate hairs, the shape, the color, the basioscopic pinnae and the overall shape.
Our taxonomist, Zac Hill, very quickly uncovered a recent paper by Kiyotaka Hori, et al (2017) which explained and beautifully illustrated our conundrum. The triploid produces a wider, far more pentagonal frond with a less erect nature in the way the blade is held, and a deeper green, highly pleasing color—now that’s pretty darn cool! This new discovery we have named ‘Yushan 2 X 4.’ A new plant for us all to grow in the years to come and now you know why we chose the name diploid (2) X tetraploid (4).
Now that we realize we grow seven different forms of Dryopteris bisettiana, each collection will be given a cultivar name, which will refer back to their specific origin and uniqueness.
Every day brings discovery when you manage a collection of 30,000 taxa but one thing we know for sure, these are amazing, well-behaved, slow growing woodland plants that are the essence of what makes Juniper Level Botanic Garden so amazing.
Patrick McMillan, director of horticulture and gardens
Hori, Kiyotaka, L. Kuo, W. Chiou, A. Ebihara and N. Murakami. 2017. Geographical distribution of sexual and apogamous types of Dryopteris formosana and Dryopteris varia (Dryopteridaceae) in Taiwan. Acta Phytotax. Geobot. 68 (1): 23-32.
You’re so Vein…Anastomosing, that is
Nurses and plant taxonomists are among the few fields in which you would run into the term, anastomosing veins. Having been in the plant world all my life, I had never even run into the term until trying to key our some bamboo ferns in the genus, Coniogramme, almost a decade ago. It turns out that to distinguish between species, you need to determine if the spore patterns on the back of the leaf have an anastomosing or parallel vein pattern. Anastomosing veins are those which diverge and reconnect forming a pattern like a snake skin. We’ve grown quite a few ferns, but none have the amazing vein patterns of coniogramme. Below are the leaf backs of Coniogramme japonica in fall.
Here’s a garden shot just prior to our expected first freeze of the year. Foreground to back: Muhlenbergia lindheimeri, Salvia darcyi, Juniperus conferta ‘All Gold’, Cuphea micropetala, Salvia ‘Phyllis Fancy’.
Juniperus communis is a common landscape juniper with a wide natural distribution…one of the widest of any woody plant in the entire world.
In the North American part of its range, it’s widespread throughout the Western US, and across the northern tier of the country all the way to Maine. East of the Mississippi River, however, it’s virtually not-existent south of the Great Lakes.
Patrick McMillan had been telling us about a population he rediscovered from an earlier Henry William Ravenel (1814-1887) documentation of a single clone growing naturally in Aiken, South Carolina. Last week, we made the 4 hour drive to visit this ancient living fossil. Here is all that remains, growing in an amazing nature park, known as Hitchcock Woods, where it grows surrounded by a forest of Kalmia (mountain laurel).
We have this propagated and growing at JLBG, and hopefully in the future, when our plants get larger, we can share these amazing genetics with a wider audience.
Looking great this week are most of the desert ferns, especially the wonderful Cheilanthes tomentosa. So many folks still don’t realize that an entire group of ferns grow naturally in desert conditions, often alongside cactus. This fern favorite has a shockingly large and unusual distribution, from Arizona east to Virginia. We’re fascinated why this evergreen fern known as Wooly lip fern, isn’t more widely grown. Hardiness is Zone 6a-8b, at least.
One of our most amazing dwarf ferns is our 2008 Taiwanese spore collection of Microsorum brachylepis ‘Datun’. Our garden patch pictured below, which is looking great this month, was planted outdoors in 2017, and is now 4″ tall x 3′ wide. We offered this personal favorite a few years through Plant Delights, but the sales were rather miserable…what a shame. This delightful evergreen makes a superb, dense groundcover. Hardiness is Zone 7b-10b.
Ajuga ‘Parrot Paradise’ is one of many new next generation colorful ajuga groundcovers that have hit the market in the last few years. These have been amazing in our trials, as you can see from the October photo below. Best of all, we haven’t seen any seedlings, which have been a problem with several of the more common clones in commerce. We think both the color and growth habits are truly outstanding.
Adiantum capillus-veneris ‘Bermuda Run’ is looking exceptional in the garden this fall. Actually, it looks exceptional most of the year for us. Until the temperatures drop below 12 degrees F, this amazing fern remains evergreen. This fern has a huge native range, being found on every continent except Antarctica.
Adiantum capillus-veneris, along with a couple of pteris fern species are often found growing in mortar cracks in many of the Southeast coastal cities and adjacent tropical islands. It is thought that some of these populations may have been spread along the early trade routes. This particularly dense form is our collection from the mortar walls on Bermuda. The same species is native to North Carolina, but only in a solitary population. Winter hardiness is Zone 7b-10b.
With the trend for green mulch (i.e. groundcovers), we continue to trial a number of new introductions that fit the bill. One of the top performers continues to be Sedum ellacombeanum ‘Cutting Edge’ PP 28,926. This 2016 Brent Horvath introduction has thrived in both sun and light shade, making a perfect ground-hugging mat. Despite being a top performer, sales were miserable when we offered it a few years ago. We’re not sure why it sold so poorly, but we now have some lovely drifts in the garden.
Monroe’s Monkey Grass
I wonder if the late Atlanta nurseryman, W.L. Monroe had any idea what would become of his white-flowered monkey grass, that he selected as a seedling and subsequently introduced to the gardening world in 1957?
In the 65 years that’s passed since it’s introduction, Liriope muscari ‘Monroe White’ is still the gold standard by which all white-flowered liriope are judged. Here are our plants flowering this week at JLBG. Unlike most liriope, which thrive in sun, this cultivar needs light shade for most of the day to prevent foliar scorch. Our plants in the photo only get a couple of hours of direct sun, where they thrive. Winter hardiness is Zone 6a-10b.
Purr-fect Pussy Toes
We love the miniature silver mats of Antennaria parviflora (little-leaf pussytoes). This little-known North American native (Canada south to Arizona) forms a tiny, 1″ tall groundcover that’s hard to the touch. In spring, the patch is topped with short fuzzy spikes of brush-like white flowers. The plant below, which measures 1′ in width, is only 18 months old from seed, and is growing in our rock garden in a well-drained mix of 50% Permatill. Hardiness is Zone 4b-7b.
Arrange your Asparagus
Asparagus virgatus is undoubtedly one of our favorite textural perennials. How many evergreens do you know that thrive in shade with such an amazing texture, and can be cut for flower arrangements. If you’ve ever worked with cut flowers, you’ll recognize this as “filler” that you purchase with your flowers to add 3-D texture to your arrangements. Few people, however realize that it’s an easy-to-grow garden perennial.
Although in the wild, it grows along streams, it has proven to be one of the most drought tolerant plants we grow. In terms of light, an hour or two of morning sun is fine, but this South African asparagus species much prefers light shade all day. Unless winter temperatures drop below 10 degrees F, the amazing foliage stays evergreen. Hardiness is at least Zone 7b and warmer.
A Golden Native
Here’s a photo this week of one of our favorite North American native plants, Juniperus horizontalis ‘Copper Harbor’. This would certainly add significant year round color interest to any native plant garden. In our trials, this is far and away the best of the golden Juniperus horizontalis cultivars. We offered this selection for a couple of years, but there seemed to be little interest.
Christmas in June
While doing some local botanizing recently, we ran across this fascinating form of our native Christmas fern, Polystichum acrostichoides. Not only was it more compact than any others in the area, with more “orderly” fronds, but it also showed none of the typical terminal spore production that would be expected this time of year. Since this was from a future development site, the plant was rescued, and is now at JLBG under evaluation. The second photo is more typical plant for the species for comparison, growing at JLBG.
The Crevice is “Woke”
The crevice garden has “woke” for spring, with early flowering plants in full gear. Here’s a shot of one small section, featuring Delospema dyeri and Iberis simplex (taurica). We hope you can visit in person for the second weekend of our spring open house, May 6 – 8, 2022.
A Little White Lying Groundcover
False lily-of-the-valley (Speirantha gardenii) is one of our favorite early spring-flowering evergreen groundcovers for shade, but one that just hasn’t caught on with customers. Every time we put this back in production at Plant Delights, we wind up throwing out most of the crop. Perhaps one day, folks will realize what a gem this is. Hardiness is Zone 5b-8b.
Here is a clump of Calanthe ‘Takane’ in our garden in early April. This amazing and easy-to-grow terrestrial ground orchid forms a dazzling clump with age. This mass started as a single division in a 4″ pot, 17 years ago. Not only do they thrive in the ground, but in Japan, they are prized as container plants.
Calanthe ‘Takane’ is a group of hybrids between Calanthe sieboldii and Calanthes discolor, so each seedling is slightly different in flower color. The foliage remains evergreen during most winters for us, but when temperatures drop near 0 degrees F, the foliage will die back completely. Calanthes thrive best in light shade. Winter hardiness is Zone 7a-9a.
Here are images of three of the “next generation” ajuga cultivars, all selections of the Italian Ajuga tenorii. These in-ground photos were all taken at JLBG on April 1. These new ajugas don’t spread wildly or seed around like many of the older, more commonly grown offerings. We think they are pretty darn amazing! The top photo of Ajuga ‘Blueberry Muffin’ represents several plants, planted on 1′ centers. The second image is a single plant of Ajuga ‘Cordial Canary’, and the third is a single plant of Ajuga ‘Petite Parakeet’. These are actually non-staged images, unlike the highly staged, completely unrealistic, manufactured photos you often see in the Dutch-centric catalogs. Hardy from zone 4a to 9b.
Crazy Eddie’s Dunce Cap
In our cold frames, some plants will occasionally flower out of season, and that’s the case this week when one of our Orostachys ‘Crazy Eddie’ plants decided to flower out of season…fall is it’s normal time. The offseason timing won’t adversely affect the plant, and it did give us an unexpected photo moment. Because of the form of the flower, orostachys gained the common name, dunce caps, named after the pointed caps that poorly performing students were forced to wear. Of course, you’re probably showing your age if you knew what dunce caps were.
Streaked like a Comet
We treasure any plant that makes a great woodland groundcover, and are particularly smitten with the ophiopgon (mondo grass) and liriope (monkey grass) selections. We currently grow over 120 different ophiopogon accesions including quite a number of wild collections, at JLBG…see what a touch of OCD does for you. We’ve grown Ophiopogon ‘Comet’ since 1997, and love it for its white striped foliage and well-behaved growth habit. Hardiness is Zone 7b-10b.
The first plant looks for all the world like a fine textured carex, but in fact, it’s an iris. Iris dabashanensis is a little-known species from China, that thrives for us in light shade, but will also take a few hours of early morning sun. Our plant is a Darrell Probst collection from Sichuan, China. Winter hardiness is Zone 5a -8a.
Below is the same plant flowering in early April.
The other plant growing nearby in our gardens that fools even the keenest plantsmen is this liriope look-alike. In fact, this is a cast iron plant, Aspidistra linearifolia. This demonstrates why those pesky taxonomic traits matter. In 2008 we introduced a selection with a lighter central stripe down the center of each leaf called A. linearifolia ‘Skinny Dippin’ which we will be offering again in 2023. Winter hardiness is Zone 7b and warmer.
Weeping cast irons
Most gardeners know the genus aspidistra (cast iron plant) from one or two species, and if that’s the case, you probably only know those which hold their leaves vertically upright. There are equally as many species with pendant leaves, which provide a completely different form in the woodland garden. Here are two of those pendant-leaf species from the garden this week.
The first is Aspidistra sichuanensis, which is one of the larger growing species. A single clump can easily spread to 6′ in width in a couple of decades. This clump has topped out at 3.5′ in height.
Below that is Aspidistra ebianensis ‘Flowing Fountains’. With narrower, wavier foliage, it makes a large clump, albeit slightly smaller than Aspidistra sichuanensis. Both plants are winter hardy from Zone 7b and south.
Ice n’ Roses Dilemma
Below are more of the Ice n’ Roses snow roses flowering now in the gardens at JLBG. These amazing sterile hybrids were created in Germany by the Heuger plant breeding company. They have proven fabulous in our trials, but are still often difficult to find due to the screwy production cycle.
Because these snow roses, as Heuger calls them, are clonal and sterile, they can only be commercially produced by tissue culture, which is all done overseas. The non-rooted microplants are shipped in sterile containers to the US, where they are received at rooting stations (nurseries capable of putting roots on these microplants).
There are only three North American rooting stations used by Heuger, one in Canada, and one on each of the US coasts. Once the microplants have roots and have grown large enough, they are purchased by finish growers, who pot and grow them for 2-3 months before they are a saleable size.
For a finish grower or retail nursery to have plants available to sell in late winter or early spring, they would need to receive liners (small plants with roots) from the rooting stations in September/October. The problem is that these rooting stations usually get their unrooted microplants from overseas in fall, when their losses are less and the plants finish faster.
Consequently, these rooting stations only have plants available for the finish growers from February – April. This means that the finish grower and retailer will only have plants ready to sell at the beginning of summer, which is certainly not ideal unless you live in the northern tier of states or Canada.
The only option a finished grower has is to hold the plants through the summer and fall, to have them available in the late winter flowering season. This drives up the crop cost dramatically, since a nursery has an overhead cost per square foot per month of growing space. Until a change is dictated by the grower throughout the supply chain, it is unlikely that the supply will be able to keep up with the potential demand. Anyone think making plants available is easy?
The Spectrum of Siblings
Throughout the years, we’ve grown literally thousands…perhaps 10s of thousands of seedlings of the Japanese sacred lily, Rohdea japonica. Each one varies slightly, but we only save those at the far end of the bell curve. Here are three of our seedlings which well represent that dramatic variation at each end of the spectrum…a wide leaf form we named Rohdea ‘Stork Nest’ (15 yrs old), a very narrow leaf form we named Rohdea ‘Thin Man’ (16 years old), and a miniature that has yet to be named.
We have long loved small crevice-sized succulents, but have also killed far more than our share, due mostly to our wet, cold winters. The newest star in our trials is the South African, Rabiea albipuncta, a first cousin to the better known, Delosperma. We should mention, that new DNA research has actually suggested a name change to Nananthus vittatus would be more correct, so we’ll be re-tagging shortly.
This gift from Denver Botanic Garden plantsman extraordinaire, Panayoti Kelaidis, has thrived in the gardens since 2018. We actually tried this back in 2004, but our site simply didn’t drain well enough in winter. This image was taken here at JLBG on February 2 this year, which shows how insanely tolerant the flowers are of cold weather. We hope to make this available next year through Plant Delights Nursery. This gem forms a substantial caudex, and as such is highly prized by bonsai enthusiasts.
We love the evergreen ruscus in garden, but realize they are a plant that will never be found at most mainstream garden centers. A genus of only 6 currently recognized species, native from Europe into Eurasia, these horticultural oddities are so odd that they once qualified to have their own plant family, Ruscaceae.
Now, with improved DNA testing, they were found to actually be members of the Asparagus family. Exactly where within the Asparagus family is still an ongoing debate. Within the last decade, they were grouped with Nolina and Dasylirion, which to those of us who work with live plants, made no sense. Most likely, they will wind up in their own section, but as distant cousins to better know genera like Rohdea and Liriope.
Ruscus are great evergreen plants for dry shade, in regions where they are winter hardy, which is usually Zone 7b and south. Ruscus are unique in that they don’t produce leaves, but instead have leaf like structures known as cladodes, from which the tiny flowers emerge. All ruscus species have both separate male and female plants, although there are four hermaphroditic (bi-sexual) cultivars of Ruscus aculeatus in commerce, which produce the lovely red fruit without a mate.
The most common ruscus species in cultivation is Ruscus aculeatus, which has a wide range from Western Europe through the Caucuses. A handful of named cultivars of Ruscus aculeatus can be found in the gardens. Below is a photo this month of Ruscus ‘Sparkler’ a self-fruiting form, whose 2′ tall height is mid-way between Ruscus ‘Elizabeth Lawrence’ and Ruscus ‘Wheeler’.
Ruscus hypophyllum is a species, which ranges from Spain to Northern Africa, that’s rarely cultivated in the US. Other than the very tender Ruscus streptophyllus, this has proven to the be the next most tender species. Prior to trying these new forms of Ruscus hypophyllum, which were planted in early 2020, we had only grown a single clone, which had consistently died in our Zone 7b winters. These new plants are seedlings, grown from an Alan Galloway seed collection in Majorca, Spain.
Ruscus hypoglossum, which hails from Italy to Turkey, is a similar sounding species that we were fortunate to study in the wilds of Slovenia a few years ago, where it grew in mountainous open forests.
Ruscus x microglossum (below) is a natural hybrid between Ruscus hypophyllum and Ruscus hypoglossum…quite a tongue-full.
Ruscus colchicus is a species we fell in love with during a trip to Hillier’s Arboretum in 2005. Hailing from NW Turkey to the Western Caucuses, Ruscus colchicus is possibly the most elegant garden species. We are fortunate to have three different clones growing at JLBG, which we hope to one day have enough to share.
Voted least likely to be found in an ex-situ plant collection is Ruscus hyrcanus, a species, whose native range is from the Crimea into Iran. In appearance it somewhat resembles a dwarf, horizontal-growing version of Ruscus aculeatus. We are thrilled to have been able to offer this little-cultivated species in the past through Plant Delights.
We hope you’ll take notice of these great evergreens during your next visit to JLBG.
Another of the mid-winter flowering species of wild ginger is the Chinese Asarum ichangense. Here is a green leaf form of this easy-to-grow wild ginger in late January from the top. If you push aside the leaves, you’ll see the amazing floral show, hidden beneath. Winter hardiness in Zone 6b-8b, and possibly colder.
A Characias Cracker
For years, we struggled to grow the Mediterranean/Balkan native spurge, Euphorbia characias…until we discovered its secrets. First, it isn’t a long lived plant to begin with…in most cases 3-5 years is it, so you’ll need to plant it where it’s likely to reseed. That would be well-drained slopes that are either mulched or covered with gravel.
Secondly, after it flowers in spring with its stunning show of yellow flowers, remove most of the flower stalks as soon as flowering has finished, except those needed to produce new seedlings (the flowers are also great to use in floral arrangements). If not, the seed stalks use up energy causing the plant to decline much faster. We’ve now allowed this to seed throughout the slopes in front of our house, and here is the result…a smattering of 3′ tall x 3′ wide clumps, photo taken mid-winter.
Although this section of the garden, planted in compost-amended sandy loam is irrigated, we typically don’t recommend irrigation for this spurge without excellent drainage. You’ll also read on-line that Euphorbia characias doesn’t like hot, humid summers…another example of fake gardening news that just keeps getting repeated without any concern for the facts.
We’ve also found Euphorbia characias to grow well in part sun under large trees, which keeps the soil dry. The plants will never be as dense as they are in full sun, but they survive and flowers. There is really not anything else that gives you this evergreen blue color and form in the winter garden.
bloomin’ Ice n’ Roses
The Helleborus x gladorfensis hybrids, known as the “Ice n’ Roses” series have begun with the opening of Helleborus ‘Ice n’ Roses Barolo’. This is the earlies flowering and darkest clone in the series…just a shade darker than H. ‘Ice n’ Roses Red’. These are sterile hybrids derived from crossed of Helleborus niger with Helleborus x hybridus. Winter hardiness is Zone 5a-8b.
Artist’s Palette in Winter
Asarum hypogynum ‘Artist’s Palette’ is in full flower here at JLBG in late January. Despite being first published in 1915, this little-known species is very poorly represented in ex-situ plant collections worldwide. Our clone is a division from a wild plant we brought back from our 2008 botanical expedition to Taiwan. The foliage on this species is some of the largest in the entire genus. For us, Asarum hypogynum starts flowering in late summer and continues most of the winter. We are working to eventually be able to share this with other collectors. Hardiness is Zone 7b and warmer.
A Major Minus
Asarum minus ‘Cupid’ is one of our heavily silver patterned selections of our native wild ginger. When cold weather arrives, the evergreen leaves take on a lovely purple cast. This is an excellent clonal selection we made in 1994 from a construction site, and one we hope to offer in the future though Plant Delights Nursery.
Lithophytes, epiphytes, tigers, and bears…oh my
Just out in the garden in early January and wanted to share photos of a few of our favorite evergreen ferns that would rather not be growing in the ground. In our garden, these are all growing within a few feet of each other.
Each of these ferns are epiphytes, which grow attached to a tree, or lithophytes, which grow attached to a rock. None of these ferns actually need soil to grow, since they get their food and water from the atmosphere and accumulated organic debris. Epiphytes, however, don’t get nutrients from their host plant…only physical support.
All epiphytic ferns thrive in hanging baskets, especially the spaghnum-lined type, since this most closely mimics their natural preferences. In our case, we are a bit colder than their native haunts, so for us, we force these ferns to reside in the ground since that gives them a bit more protection during severe winter temperatures. The key for epiphytes to survive in the ground is to have very loose, organic soils and always plant them on a steep slope.
Neolepisorus fortunei ‘Green Ribbons’ is our 2017 introduction of a Chinese native epiphytic fern.
Pyrrosia lingua ‘Hiryu’ is also an epiphytic fern, native to Japan.
Lastly is Polypodium vulgare ‘Ulleung Island’. Instead of being an epiphyte, this evergreen fern is a lithophyte. Lithophytes are classified as either epilithic (growing across the rock surface) or endolithic (growing in cracks or crevices). Since we found this in the wild, growing across the surface of a giant rock, this fern is an epilithic lithophyte…say that three times fast. This is our 1997 collection from an island, far off the coast of South Korea.
We hope you’ll explore these unique ferns in your garden.
Rohdea japonica ‘Shishi’ is looking lovely in the woodland garden. Rohdea ‘Shishi’ is a dwarf Japanese selection of the evergreen sacred lily with leaves that curl downward creating an unusual bird nest like appearance. Winter hardiness is Zone 6b-8b.
Flowering Tractor Seat
We recently had someone inquire if we grew tractor seat plant, a common name I had not heard prior. After a brief pause, I figured few plants, other than our 2000 introduction, could possibly fit that name. Sure enough, a quick web search confirmed that Farfugium japoncium var. giganetum ‘Marco’ is indeed their target. While wandering through the garden this weekend, I found one clump still in flower, that somehow avoided damage from several nights at 27 degrees F.
To our knowledge, this giant form of Farfgium japonicum, native Japan’s southernmost Ryukyu Islands, was first brought to the US by plantsman Marco Stufano, who rationed out one plant per year for a NY Rare Plant Auction. When Marco was ready to retire from Wave Hill, he finally shared a piece with us, so we could get it mass propagated, hence we named the clone in his honor. To our knowledge, all tractor seat plants sold in the US came from Marco’s original plant.
One of several rare wild gingers we grow is Asarum lewisii, which has a small native range limited to central NC and adjacent Virginia. In the wild, the evergreen Asarum lewisii is quite unique in only producing a single leaf every few inches to over 1′ apart when growing in leaf duff. In the garden, however, leaves are much more dense as you can see in the photo from the JLBG gardens this week. It’s ashamed it doesn’t sell better when we offer it through Plant Delights.
Mr. Butterfield’s Fern
We love the evergreen holly fern in all it’s species and forms. Cyrtomium falcatum ‘Butterfieldii’ is looking absolutely stupendous in the garden this month. This easy to grow shade lover glistens all winter with its glossy foliage with fancy serrated edges. Hardiness is Zone 7a-8b.
The cast iron plant, Aspidistra tonkinensis ‘Hanoi Honey’ has been looking quite stunning recently during its December flowering period. Unlike many cast iron plant that have reddish cinnamon flowers, this dazzler has large bright white flowers that are impossible to miss. Where it isn’t winter hardy, cast iron plants make fabulous, easy-to-grow house plants.
Slim and Trim
Anyone who has visited JLBG, knows we are huge fans of the Japanese sacred lily, Rohdea japonica. While the variegated forms are certainly showy, we also love the solid green varieties, especially the narrower leaf forms, so here are a few of our favorites. The top is Rohdea japonica ‘Fukuju Kan’, followed by Rohdea ‘Feelin’ Groovy’, and finally Rohdea ‘Line Dance’. All photos were taken in our gardens this week. For us, these amazing evergreen plants remain looking great all winter and the orange-red winter fruit are a bonus. In the garden, they function like evergreen hostas. The first two are what is known as dragon-ridge (crested) varieties. Hardiness is Zone 6b-9b.
The dwarf groundcover Sedum tetractinum ‘Little China’ is superb throughout the growing season, but we particularly love when cold weather arrives and the olive green foliage turns to bright red in the sun…what a superb winter show. Hardiness is Zone 4a-8b.
Proud to be a Siberian
We don’t have many Siberian plants which thrive in the southeast US, so we get pretty excited when we find one that does. I was introduced to Microbiota decussata by the late JC Raulston, back in the mid 1970s, and actually still have one of my original plants that’s still alive. Many years later, a much improved form came to market under the name Microbiota decussata ‘Prides’.
Microbiota is a monotypic genus of conifer that has a textural appearance somewhere between a Juniper and a Selaginella. In the wild, Microbiota can only be found in one small region of the Sikhote-Alin mountains, which is about 500 miles north of Vladovostok, Russia, where it occurs between 6,500′ and 7,000′ elevation.
Although Microbiota was officially discovered in 1921, and published in 1923, the Russian government, long-known for its secrecy, kept it completely under wraps until the early 1970s.
Unlike most junipers, which need sun to thrive, microbiota prefers shade to only part sun. Consequently, it you like this texture and don’t have full sun, this is the plant for you. For us, it matures at 18″ tall x 6′ wide.
Reineckea…the unknown cousin
Most gardeners in mild winter climates are familiar with Liriope (monkey grass), and Ophiopogon (mondo grass), but almost no one is familiar with the third cousin, reineckea (false lilyturf). Like both better known cousins, reineckea is an evergreen groundcover, but unlike the others, here is our clump of Reineckea ‘Little Giant’ in full flower for Thanksgiving. Depending on your taxonomist, there is between 1-3 species in the genus. We’re certain of three and think there may be more. We have assembled a collection of nearly 30 wild collections and will be working with other researchers to sort out the taxonomy of this group.
One of our favorite fall woodland plants is a member of the Aster family, belonging to the genus farfugium. Farfugiums have long had a bit of an identity crisis, as they were originally named in 1767 by Linnaeus as Tussilago japonicum. In 1768, the same plant was also published as Arnica tussilaginea. Then, in 1784, it was moved to the genus, senecio, and became Senecio japonicus.
Later in 1891, it was renamed again, this time as Senecio tussilagineus. It remained in the genus senecio until 1904, when it moved to the genus Ligularia, and became Ligularia tussilaginea. Here it remained until 1939, when it became Farfugium tussilagineum, but corrected the same year to match Linnaeus’s original epithet, resulting in Farfugium japonicum, which it remains today.
Below is our plant of the typical species, Farfugium japonicum in flower at JLBG this week. Through the decades, we have been collecting an array of other forms. Light open shade or a tiny bit of morning sun and average to slightly moist soils produce the best results.
Farfugium ‘Roundabout Fall’ is our selection of a hybrid with our Taiwanese collection Farfugium japonicum var. formosanum and the typical form. We like the smaller, thick, rounded leaf shape.
Farfugium ‘Jagged Edge’ is another upcoming JLBG/PDN introduction, scheduled for a 2023 release. It forms one of the larger clumps of any farfugium cultivars we’ve grown.
Farfugium ‘Bashi Ogi’ is the only cultivar we know of Farfugium japoncium var. luchuense. This rare variety hails from Japan’s southern Ryuku Islands of Okinawa and Kagoshima. It differs in appearance by being a much smaller plant with leaves which are wider than tall. Here is our plant flowering now here at JLBG.
For 2022, Plant Delights will introduce JLBG’s first selection of Farfugium japonicum var. luchuense, that we’ve named Farfugium ‘Sweet Spot’. It’s a miniature seed selection from the above Farfugium ‘Bashi Ogi’, that only gets a few inches tall, so will make a great house plant, where it isn’t winter hardy.
We love ferns of all types, but especially the single-leaf types. Our clump of the Chinese Lepisorus macrosphaerus really stands out in the fall and winter garden. In the wild, most lepisorus grow on rocks or tree trunks, but most we’ve grown have adapted well to growing in the soil. They tend to thrive better when growing on slopes, and in well-drained soils.
Green Eggs and ….pancakes?
Most everyone is familiar with Blue rug juniper…aka: Juniperus horizontalis ‘Wiltonii’, but few people know its dwarf cousin, Juniperus horizontalis ‘Pancake’. This amazing selection of the North American native groundcover is much slower growing, shorter, and with much finer textured foliage. Here is a recent photo of this amazing plant in the gardens at JLBG. Why is it that we never see Juniperus horizontalis touted for native plant gardens…hmmm?