Aroid Passion – Purple Dragon

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 purple undersides of the foliage are visible, along with the green hooded flower.
Pinellia x cortita ‘Purple Dragon’

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.

Pinellia x cortita 'Purple Dragon' in the woodland garden
Pinellia x cortita ‘Purple Dragon’

The Cobras of Summer

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.

Arisaema candidissimum
Arisaema franchetianum
Arisaema purpureogaleatum

Hi Jacks

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.

Arisaema triphyllum Wake County, NC

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.

Arisaema triphyllum silver veined clone
Arisaema triphyllum silver veined clone with green stems
Arisaema triphyllum silver veined clone with purple stems

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.

Arisaema triphyllum with rust induced pattern
Arisaema triphyllum rust induced pattern on leaf back

Meet Jack from Ilan

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.

Shaking up Saxatile

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.

Arisaema saxatile

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.

Arisaema saxatile in seed

Sex in the Pulpit

After being told several years ago that creating interspecific hybrids of arisaema (Jack-in-the-Pulpit) was virtually impossible, we started our own breeding program. Here are a few of our creations from our Contrarian Frankestein Lab that are looking quite nice this week.

Arisaema x heterburgii ‘Black Snake’ (heterophyllum x thunbergii)
Arisaema x heteroguineum ‘Pirate Sail’ (heterophyllum x consanguineum)
Arisaema x trigesii ‘Neptune’ (triphyllum x fargesii)

Jack of all trades

The Japanese Arisaema sikokianum (Jack-in-the-pulpit) posing with Hosta ‘Kabitan in this glamour shot.

A quick trip to Washington DC

Katie B at Chinese Bonsai Pavillion, USNA

I’m just back from a quick trip to Washington DC with my stepdaughter Katie.  We first stopped at the US National Arboretum to spend some time with the new director Richard Olsen, who shared his excitement about many of the exciting plans and projects underway at the people’s arboretum including the renovation of the Chinese bonsai pavilion. Virtually all of the projects and expansions are privately funded.

While it was exciting to hear that the future looks bright, it was equally shocking to see the horrific state of maintenance and weeding due to continuing Congressional budget cuts to the arboretum’s funding.  The Federal government seems to have no understanding of funding for maintenance.  It’s a sad reflection on our country for visitors from around the world to see our country’s National Arboretum like this. I hope you’ll join me in calling your representatives and voice your concern!

Arisaema ringens x heterophyllum at USNA 19647

One of the really interesting finds in the garden was a spontaneous jack in the pulpit hybrid…a cross of Arisaema heterophyllum and Arisaema ringens.  This is the first spontaneous arisaema hybrid that I’ve ever heard of.  We need this!

Then, it was off to speak at the International Pteridological Convention at the Smithsonian.  Over 250 fern researchers, half from outside the US, showed up to share their latest fern discoveries and research.  It was a great chance to meet so many amazing people.  Katie videotaped my talk and we’ll post it on our You Tube channel soon.