Sometimes you see a plant, or a photo of a plant, that raises your horticultural lust to somewhat unhealthy levels. At this point in life, that happens far less than it used to, but one plant that remained on my lust list for over a decade was the aroid, Pinellia ‘Purple Dragon’.
For those who aren’t familiar with pinellia, they are an Asian genus of only 9 species of hardy woodland aroids, related to Arisaema (Jack-in-the-Pulpit). I will admit to have eliminated most pinellias from the garden because they grow too well, and spread too prolifically.
The only Pinellia species we retained in the garden are the non-weedy Pinellia cordata and Pinellia peltata, which don’t move outside of a small area. Pinellia hybrids have also always intrigued us. The first hybrid to be named was from the former We-Du Nursery, Pinellia ‘Polly Spout’ (P. pedatisecta x tripartita), and is sterile unless it is grown near one of it’s weedy parent species. We have grown this in the garden since 2004, and it remains a solitary clump, producing no seed.
When we heard of a second hybrid (P. cordata x tripartita), the search was on. Pinellia x cortita ‘Purple Dragon’ showed up at NY’s Glover Perennials, which unfortunately doesn’t ship. We finally tracked down a plant in 2019, and have subsequently fast-tracked it in the production process, so we could share this amazing gem that excited us so much. As we expected, none of our plants have ever produced a single seed.
The only problem with the plant is the cultivar name Purple Dragon, which has been used for years as the common name for the purple-spathed form of the weedy Pinellia tripartita, which sadly many folks will probably confuse with this new sterile hybrid.
Pinellia ‘Purple Dragon’ is effectively an everblooming arisaema, with flowers being produced non-stop from spring into fall. The new foliage emerges dark purple and opens olive green on the top and purple underneath. This has proven to be an exceptional plant in our garden. Our trial plant in half day sun has thrived as well as our specimens in more shade. If you like Jack-in-the-Pulpits, we hope you enjoy this new treasure as much as we do.
I had to chuckle as folks on several Facebook plant groups were wringing their hands in worry prior to the recent cold snap, while we were secretly hoping for even colder temperatures than forecast.
JLBG registered three consecutive nights in the teens recently; 11F, 19F, and 19F. While this was certainly not abnormal for our area, folks with very short memories thought the horticultural world was coming to an end. In reality, we recorded similar temperatures in the winter of 2017/2018, albeit a week later that year.
When we first started the gardens at JLBG, we were squarely on the Zone 7b side of the Zone 7a line. We are now on the Zone 7b side of the Zone 8a line. In order words, we have shifted about 1/4 of a hardiness zone. Since 2018, JLBG has registered three consecutive Zone 9a winters, so it’s not surprising the new gardeners or those with short memories start assuming that all kind of plants are reliably winter hardy, which is not the case.
We long for cold temperatures because we want and need good winter hardiness data, and while mild winters may be enjoyable to us Homo sapiens, we don’t learn anything about plant hardiness from those winters. So, here are a few things we learned this year.
Agave weberi ‘Stone Cold Austin’ is Patrick McMillan’s collection of Agave weberi from Austin, Texas. We’ve tried Agave weberi a couple of times prior, and could never get it through one of our milder winters. Patrick’s original plant at Clemson got large enough to flower there, so we’re hoping for the same. The older foliage is showing damage from 11F, and will most likely be lost, but the bud seems fine so far.
We’ve never had any luck with any of the dwarf Agave lechuguilla mutants we’ve tried in the garden, but this new one, shared by plantsman Hans Hansen, that we call Agave ‘Tater Tot’, had no problem with 11F. These are often sold as Agave x pumila, which actually doesn’t exist. Everyone assumed that A. x pumila was a hybrid, but when one in Europe recently mutated back to the original form, it turned out to be nothing more that a super dwarf form of Agave lechugullla.
Mangave ‘Racing Stripes’ is a plant we had high hopes for in terms of winter hardiness, but we had not had a cold enough winter to get good data. Our only reservation was that it contains genes from the tropical Agave gypsophila. Thankfully, our plant came through the 11F freeze in reasonably good shape. The wrinkled nature of the older leaves are indications of cold damage that will show up in a few more days, but the core seems intact and should re-grow.
We fully expected Bambusa multiplex ‘Green Giant’ to be defoliated after 11F and the stalks killed to the ground, but our fully exposed clump still looks like it’s mid-summer…at least from the north side.
On the south side, the same clump has fried foliage. There are typically two causes for such damage. One is wind desication when the winds are blowing from a single direction and the ground is frozen, making it impossible for the plant to replenish water lost through the foliage. During the time that our ground was frozen, our winds were coming from the West, so that wouldn’t account for damage only on the south side of the plant.
In this case, the more likely scenario is that this is due to sun scorch when the soils was frozen, since the damage is on the south side. If the canes are indeed undamaged, as it appears, new leaves should reflush in spring.
We didn’t hold out much hope for the Mexican palm, Brahea decumbens, but it sailed through 11F unscathed.
Since we know that genetics matters, we will often plant more than one clone of a marginal plant like a new palm. Below are two seedlings of the small-seeded European Fan Palm, Chamaerops humilis var. microcarpa. The first shows significant foliage burn, while the second plant, growing nearby shows no damage after 11F.
The hardiest of all Sabal palmetto forms are those from NC’s Bald Head Island. Our plant from there came through the cold unscathed. We expect many local businesses and even homeowners who purchase large trunked forms directly from Florida growers will probably be in for a disappointing spring.
All of our hardy cycads have assumed the straw-color we see every year when the temperatures drop below 18 degrees F. The plants are fine, but we recommend waiting to remove the dead fronds, since doing so now, can cause the new foliage to emerge in the middle of winter, which is never a good idea. April 1 is our target date to remove the fried foliage.
One of the real surprises was the fried foliage of Viburnum ‘Moonlit Lace’, where it was growing in full sun. The same plant growing in shade looks untouched. The stems are fine and the plant should re-sprout fine, but gardeners who grow this in full sun may be disappointed.
This is the coldest temperatures we’ve seen since planting Patrick’s hardy selection, Opuntia microdasys ‘Dripping Springs’. Our clump looks great after the cold. It’s hard to imagine that this clone is so much more winter hardy than any of the other forms of this species that we’ve tried previously and killed at much warmer temperatures. Although we don’t offer this for sales, I’ll remind you of our great prickly pear cactus giveaway at our Summer Open Nursery and Garden in July.
The Mexican Sedum praeltum looks a bit sad, but actually seems to be fine with sound buds up and down the stem. This little-known perennial forms a plant that looks almost exactly like the tender Jade plant, Crassula ovata.
Lastly, our patches of Living Stones, Lithops aucampiae, sailed through 11 degrees F. I wonder if we can ever get all the disinformation on the Internet regarding their tolerance to cold corrected.
Several plants emerge in the fall/winter season…some native, and others from far away Mediterranean climates. One of the most unusual plants we grow is the pig’s butt arum, Helicodiceros muscivorus. Depending on the location of the original population on one of the Mediterranean islands, it can emerge in our climate as late as February or as early as December. Here is a photo of our plant of an Alan Galloway collection from Majorca, which is the earliest to emerge in our garden. Let’s hope it’s ready for our upcoming cold snap. Even if this never flowered, we marvel at the glaucous, three-dimensional Escher-esque foliage.
I’m just back from a recent plant trip to coastal Virginia and wanted to share some trip highlights and photos. Mark Weathington of the JC Raulston Arboretum and I headed north for a quick 2 day jaunt to the Norfolk area of Virginia.
Our first stop was the garden of long time garden friend, Pam Harper. For decades, Pam was probably the most prolific and knowledgeable garden writer in the country, in addition to having what was once the largest horticultural slide library.
At 92, and despite suffering from debilitating eyesight issues, Pam still gardens, including planting and pushing carts of mulch around the garden. It was such a joy to once again walk her amazing garden, listening to the both the historical details and performance of each plant we passed.
Pam was donating the remainder (20,000) of her slide collection, which previously numbered over 100,000 images, to the JC Raulston Arboretum. There, they will be digitized for public availability.
Her 45 year-old Camellia sasanqua ‘Yuletide’ was the largest either of us had ever seen.
We both also fell in love with Camellia x vernalis ‘Meiko Tanaka’…a plant we’d never encountered in flower, but seems to have good commercial availability.
The gold barked Japanese maple, Acer palmatum ‘Bihou’ was also showing off its stunning winter color.
Pam’s garden has always yielded some of the most amazing Arum italicum seedlings I’ve ever seen. We are already growing two of her selections in hopes of future introduction, but we found a few more that we couldn’t resist.
Our next stop was the Virginia Tech Tidewater Arboretum at the Hampton Roads Experiment Station. It had been many years since either of us had visited.
What we found was an amazing plant collection that has been mostly abandoned, except for some minimal mowing maintenance. In most cases the labeling was somewhat intact, although some required Easter egg-like hunts, and others were simply nowhere to be found.
The late Virginia Tech researcher, Bonnie Appleton had worked to get homeowners to plant shorter maturing trees under power lines. To make her demonstration more authentic, she had faux power lines installed, which you can make out among the branches. It was interesting to see that virtually all of the plants she promoted as dwarf, had all grown well into the power lines. Mark recalled conversations with her decades earlier explaining that her choices weren’t really very sound.
There were a number of amazing older specimens including one of the largest Quercus polymorpha (Mexican Oak) that we’d ever seen in cultivation. This 75′ tall specimen dated to 1989, was originally gifted to them by the late JC Raulston, from a Yucca Do Nursery wild collection.
The old specimens of Ilex buergeri were absolutely stunning. This is a beautifully-textured, spineless broadleaf evergreen that’s virtually unknown in the commercial trade.
Another spineless holly, Ilex pedunculosa (long-stalk holly), is known for being difficult to grow in our hot, humid climate. Their specimen, however, looked absolutely superb.
We caught Fatsia japonica in full flower…always a great nectar source for honeybees in the winter months.
A highlight for me was catching the amazing stinkhorn fungus, Clathrus columnatus in full splendor…both visually and odoriferously.
Leaving the Hampton Roads station, we headed to the Norfolk Botanical Garden, where Mark worked before he came to the JCRA. Much of their efforts in the fall and winter are put toward their massive winter lights festival.
Norfolk Botanical Garden is home to an extensive and renown camellia collection, so we spent a good bit of time roaming the woodland garden where they grow. We were particularly interested in their Camellia species collection, several of which had questionable labeling. Here is one that was correct, Camellia gaudichaudii.
We spent a good bit of time studying a holly, labeled Ilex purpurea (syn. chinensis). The plant was amazing, but looks nothing like that species. Hopefully, a holly expert will be able to help us identify it from our photos.
This was my first time seeing the self-fertile idesia, Idesia polycarpa ‘Kentucky Fry’. I can’t imagine why this amazing, easy-to-grow plant isn’t more widely planted. I can think of few trees with more winter interest.
The shrub/small tree that blew us away from several hundred feet was a specimen of Arbutus unedo ‘Oktoberfest’. We’ve grown Arbutus unedo ‘Compacta’ for decades at JLBG, but have never seen anything as stunning as this clone.
While we’re talking about plants with red fruit, I was fascinated with their specimen of Cotoneaster lacteus. I had mistakenly assumed that most cotoneasters fail in our hot, humid summers, but obviously, I’ve never tried this species, which is typically rated as hardy only to Zone 8a. I think we need to trial this at JLBG.
Finally, I was particularly fascinated with a Quercus nigra (water oak), that formerly had a planter built around it’s base. As you can imagine, the tree roots made short work of the planter, but once the planter boards were removed, the resulting tree root sculpture is simply exquisite.
I hope you’ve enjoyed the highlights of our recent trip.
A first cousin to the better known aroid, arisaema is the lesser known aroid, arisarum. While arisaema has a distribution that is primarily North American and Asian, arisarum is primarily European. We planted our first arisarums back in 1994, and since then have tried quite a few and killed quite a few. The best species for our climate is Arisarum vulgare, a Mediterranean native, found naturally in the countries of Albania, Algeria, Baleares, Corsica, Crete, Cyprus, East Aegean Islands, France, Greece, Italy, Lebanon-Syria, Morocco, Palestine, Sardinia, Sicily, Sinai, Spain, Transcaucasus, Turkey, and the former Yugoslavia.
With such a wide range of occurrence, some forms are naturally going to be more adaptable to our Zone 7b climate than others. The star in our trials has been a 2010 Crete collection of Arisarum vulgare from near the town of Lakki. From a tiny rhizome piece, it has spread to a 3′ wide patch. Like its’ other cousin, arum, arisarum goes summer dormant, re-emerging in fall. All of the previous forms of Arisarum vulgare we’ve grown have flowered only in early spring, but this amazing form flowers quite well every fall, in addition to being incredibly vigorous. We’ve just dug some of our patch today, and will work on propagating them for a future PDN catalog under the name Arisarum vulgare ‘Lady Lakki’. Hardiness is Zone 7b and warmer.
We are always interested in checking out the offspring, when plants in the garden have unexpected romantic rendezvous with their distant cousins…often when we least expect it. We have found arums tend to be quite promiscuous in the garden. While most offspring go to the great compost pile in the sky, a few are worthy of adoption and naming.
Below is our selection of a cross of Arum dioscorides x Arum italicum that we named Arum ‘Love Child’. While the foliage resembles typical Arum italicum, the spring-borne flowers show great influence of Arum dioscorides with the purple spotting inside the spathe. It’s our hope that Plant Delights will have a first crop of this new hybrid to share in the 2023 catalog.
Flowering today at JLBG is one of the tiniest of the geophyte aroids, Ambrosina bassii. This tiny gem, which matures at a whopping 1-2″ in height, is native to the Mediterranean region from Southern Italy to Northern Africa, where it grows on woodland slopes over alkaline rocks. There is only a single species in this little-known genus.
We always look forward to elephant ear evaluation day at JLBG, which was recently completed.
Each year, Colocasia breeder, Dr. John Cho flies in from Hawaii to study and select from our field trials of his new hybrids. This year we were joined by Robert Bett, owner of the California-based plant marketing firm, PlantHaven, who handles the Royal Hawaiian elephant ear program. The JLBG trials consist of all named colocasia introductions growing alongside Dr. Cho’s new hybrids created the year prior.
JLBG staff members, Jeremy Schmidt and Zac Hill spent most of the morning working with Robert and John on the time-consuming evaluation process.
After lunch, Jim Putnam from Proven Winners, joined us to see which remaining plants struck his fancy for potential introduction into their branded program. As you can see, lots of amazing plants didn’t make the final cut, which is necessary, since we’ll need more room for the new selections.
Plants selected for introduction are then sent to a tissue culture lab to be produced for the next step, which is grower/retailer trials. If these are successful, and the plant can be multiplied well in the lab, the plants are scheduled for retail introduction.
Hopefully, by now, most folks are familiar with our 2020 top selection, Colocasia ‘Waikiki’, which hit the market this year. There are more really exciting new selections in the pipeline, but we can’t share photos of those quite yet…stay tuned.
We’ve long been fascinated by Amorphophallus konjac ‘Shattered Glass’, an unstable variegated cultivar, developed by plantsman Michael Marcotrigiano. Some years, the foliage emerges solid green, other years with a small bit of sectoral variegation, and this year with a fully variegated leaf.
Plant nerds use the term BIO plant, short for Botanical Interest Only, for plants which have little, if any ornamental value, but are highly prized by crazed plant collectors. Spathicarpa hastifolia is such a plant. This odd aroid from Southern Brazil has actually thrived in our woodland garden since 2019. The coldest winter temperatures we’ve experienced in that period is 16 degrees F.
The small woodland plants mature at 1′ tall x 1′ wide, with oddly interesting flowers, which you can see in our image…if you squint. If this continues to perform well, and we can get it propagated, perhaps we’ll have some to share in the future. To quote our friend Bob McCartney, “We have the market cornered on plants for which there is no market.”
One of our favorite love lilies in our 2003 introduction, Amorphophallus konjac ‘Pinto’. This amazing dwarf never has foliage that exceeds 16″ in height. Unfortunately, the ridiculously slow growth rate has kept us from offering it again since, but perhaps one day. Here is our parent plant in the garden this week. Even if you don’t have a home garden, this form is superb in a container. We had a large crop of dwarfs from seed two years ago, and are looking for more unique new compact selections.
While most arisaemas flower in early spring, several members of the Franchetiana section of the genus are summer bloomers. There are five species in this section, but the only one that flowers in spring is Arisaema fargesii. Flowering recently are those pictured below, A. candidissumum, Arisaema franchetianum, and Arisaema purpureogaleatum. The debate still rages on whether Arisaema purpureogaleatum is merely a form of Arisaema franchetianum, but regardless, it has a distinct appearance when in flower. Of these three, Arisaema candidissimum is the least tolerant of our summer heat.
We love “vulgar” plants, which are good for providing unexpected shrieks from garden visitors. One of our favorite plants for evoking such moments is the European native, Dracunculus vulgaris. For those who took Latin in school, you’ll know that the English translation of the Latin name is Vulgar Dragon’s Butt. This fascinating spring ephemeral is native to very rocky, dry sites in the Southwest corner of Turkey, the Aegean Island (inc. Greece), and into the Balkans.
Virtually all of the material in commerce, which comes from the Turkish populations, are the red spathe/purple spadix form. Once you move to Crete, the inflorescences take on a different color theme with blends of white in spathe, and spadices which range from black to yellow. Below are a few which flowered at JLBG this spring.
We inherited the work of the late aroid researcher Alan Galloway, who actively hybridized dracunculus in an attempt to study the genetics as well as create new color forms for gardeners. Once final selections are made, these will require tissue culture for reproduction. Without tissue culture (dividing plants with a tiny knife), commercial quantities could never be obtained. Wish us luck!
Below are two variations on a theme…calla lilies in the garden. Here is Zone 7b, both are reliably winter hardy in the ground.
The striped-leaf selection of the winter-blooming South African native, Zantedeschia aethiopica ‘African Gold’ has looked fabulous all spring, where we have it planted in a seep, which gets full sun for 3-4 hours in the morning.
Zantedeschia ‘Picasso’ is a hybrid, created using several of the summer-flowering South African native calla lily species. Here it is in our garden in mid-June, where it gets 4-6 hours of sun daily, and the soil stays reasonably moist.
Over the last few weeks, I’ve been working on a plant survey of a local woodland area of about 30 acres. The low, moist areas are filled with Arisaema triphyllum, (Jack-in-the-pulpit) which is quite common in our area. The first image is what is typical for the species.
I’ve been studying patches of Jack-in-the-pulpit for well over 55 years, always looking for unusual leaf forms that showed any type of patterning. Until last month, I’d never found a single form with atypical foliage. That all changed with my first trip to this local site, where so far, I have found several dozen forms with silver leaf vein patterns. Up until now, there are only two pattern leaf forms of Arisaema triphyllum in cultivation, Arisaema ‘Mrs. French’ and Arisaema ‘Starburst’.
Each patterned leaf clone varies slightly as you would expect within a population including both green and purple stalk coloration.
While I’d never found any true variegation prior to this, I had found plenty of transient leaf patterning caused by Jack-in-the-pulpit rust (Uromyces ari triphylli). This site was no exception, with a number of plants showing the characteristic patterning. If you find these, turn the leaf upside down and you’ll see the small orange rust pustules.
While these may seem exciting, the pattern are not genetic and will disappear without the fungus. Fortunately, this rust can be cured by cutting off the top of the plant and discarding it where the spores can not spread via the wind. Infected plant should be fine, albeit smaller next year. The susceptibility of Arisaema triphyllum to jack-in-the-pulpit rust varies with genetics. Of the tens of thousands of plants I observed at the site, less than 10% were infected with the rust.
Here are a few buttery-colored plants flowering today in garden, starting with Arum creticum ‘Golden Torch’. This started as a small field division of a particularly large flowered selection from our 2010 expedition to Crete.
Paeonia mlokosewitschii is known for being un-pronouncable, so most folks refer to it as Molly the Witch peony. This is a particularly lovely butter yellow form from Ellen Hornig of the former Seneca Hill Perennials.
Trillium sp. nov. freemanii is a still unpublished new trillium species (hopefully soon), that we discovered in 1998. Normally red flowered, this is a rare yellow-flowered form.
Flowering at JLBG since early March is the little-known Jack-in-the-pulpit, Arisaema ilanense. This collection hails from Ilan (Yilan), in northeastern Taiwan, and for us is the very first arisaema to flower each winter, even when temperatures are still quite cold. The mature size is only 4-6″ in height, so this is one for a very special site in the rock garden. There are very few plants of this species in ex-situ conservation collections, so thanks to JCRA Director, Mark Weathington for sharing. Our specimen has been in the garden since 2016. Hardiness is unknown, but we’re guessing Zone 7b-9b.
One of the last plant exploration trips the late plantsman Alan Galloway made, was to Majorca, Spain. Alan was so excited to return home with some special selections of the fall-flowering Arum pictum, which typically has solid green foliage…except on Majorca. This beautiful form is known by collectors as Arum pictum var. sagittitifolium, although the name isn’t considered valid due to the natural variability in leaf patterns. This is Alan’s favorite form from his trip, to which we added the cutlivar name, A. pictum ‘King James’. It seems that back when Majorca had kings (thirteenth and fourteenth century), before its merger with Spain, they had a propensity for naming most of them, James.
Many gardeners are familiar with or have grown arum…mostly forms of the widespread Arum italicum, but few have grown the blingy gem of the genus, Arum pictum var. sagittitifolium. We are thankful to have this amazing collection from an Alan Galloway expedition to Majorca, Spain. Sadly, this species isn’t nearly as winter hardy (Zone 7b and warmer) as Arum italicum and we have never been able to coax it to set seed.
Here’s a recent image of the amazing Colocasia esculenta ‘Maui Sunrise’, still looking great in late October! Moist, rich soils and full sun are the key for your plants to look this spectacular! Winter hardiness is Zone 7b and warmer.
Apologies for commandeering the famed Duke Ellington line, but it seems appropriate for the new Colocasia ‘Waikiki’.
When we first met Hawaii’s John Cho in 2003, we knew some special elephant ears would be the result of our collaboration, but it was hard to imagine something like the seriously tricked-out Colocasia ‘Waikiki’. Almost every year, John, who has now retired, but is still actively breeding elephant ears, travels to JLBG to evaluate his new hybrids at our in-ground trials and make future introduction decisions. There are some seriously amazing new selections starting down the introduction pipeline.
Colocasia ‘Waikiki’ will be released from Plant Delights Nursery on January 1, so if you like this, mark you calendars and stay tuned to the website.
Most gardeners are familiar with arums, but few know Engler’s arum…aka: Englerarum hypnosum, a genus first recognized in 2013. This horticultural oddity was kicked out of several better known aroid genera (Colocasia and Alocasia) due to its odd genetics (anastomosing laticifers and colocasioid venation). The lone species of Englerarum can be found in forests from Southwest China to Southeast Thailand, where it grows as a lithophyte (lives on rocks) on karst limestone, spreading by rhizomes to form large colonies. It has been surprisingly winter hardy for us, surviving upper single digits F, when growing in typical garden soils, where it reaches 5′ in height with 30″ long leaves. Here is our patch at JLBG this summer.
For two decades, we’ve grown the amazing Chinese jack-in-the-pulpit, Arisaema saxatile with its delightful lemon-fragranced flowers. The most frustrating part was its slow offsetting nature, which meant we rarely had any to share.
Eighteen months ago, we dug our main clump and moved most of it from a well-shaded site to a location that would get a couple of hours of afternoon sun. To our surprise, it loved the new site, where this summer, it produced two large seed heads which will be harvested shortly. This is the first sign of seed in 20 years, so hopefully in a few years, we have some good numbers to share.
Just flowering at JLBG is our largest clone of the hardy aroid, Dracunculus vulgaris, that we named ‘Supersize’. This one produced a massive 30″ inflorescence. A typical length is 15-20″. We’d be curious is anyone has grown one any larger. As you can imagine, it was quite a feast for the pollinating flies.
Flowering in the garden now are the amazing and very rare white-flowered Dracunculus vulgaris. This wild and crazy aroid, which typically has a red/purple inflorescence, hails from the Mediterranean region, centered around Greece and Turkey. The late aroid guru Alan Galloway worked extensively to breed these, and since we now hold his collections, we wanted to share the wonder of his work. It is our hope that tissue culture will be able to make these amazing color forms available one day.