Jack-in-the-Pulpit - Arisaema

1/7/2024 4:34 pm

 

 

 

 

 

☑︎ Shade grower

☑︎ Dramatic flowers

☑︎ Dramatic foliage

☑︎ Dramatic seedpods

 

If these characteristics appeal to you, then you should be growing jack-in-the-pulpits, plants in the Arisaema family.

 

General Info

 

Arisaemas are characterized as intermediate between tubers and rhizomes, coming in either disc or cigar shapes. They may have petioles (stems from which leaves form) or pseudostems (false stems made from the bases of rolled leaves).  Some species bloom off petioles or on top of pseudostems. The interesting parts of the inflorescenses are the spathe (pulpit) -- which is a modified leaf -- and the spadix (jack), which carries the flower parts. There are significant variations in pulpit and jack appearances among species of Arisaema. Leaf arrangements, bloom time and leaf persistence are also variable. This variability is what makes them so interesting to me. 

 

Arisaema reproduction is fascinating too.  Most young plants begin as male. Plants often change sex as they mature to bloom. Some will change back to male after blooming. Some species carry both male and female parts in multiple inflorescences or a single one. This is the stuff botanists study with glee. For me, its an advisory that sometimes you need two plants to get blooms and make babies and sometimes you don't. Look for specific species information to learn what you need.

 

After Arisaema flowers, you may get seed pods of either sex on a plant. Swollen ovaries are the key to identifying a female bloom which will proceed to redden over the course of months.  Arisaema are primarily pollinated by flies, fungus gnats and beetles, but they do not carry any noticeable offensive odor like relatives in the Aroid family, particularly Amorphophallus or Sauromatum.

 

 

Fresh seed that drops to the ground and is lightly buried to hide it from the birds may germinate well. I've also been pleasantly surprised at how well fresh seed placed in potting medium germinates. Tidy up the seed pods if you don't want more plants. This year I used seed pods from A. consanguineum as a long-lasting "holiday" tree decoration outside.  Do not try this inside with pets -- seeds contain calcium oxalate which can burn pet throats and cause cardiac issues.

 

 

 

Some Arisaema don't seed as easily as A. consanguineum or A. sikokianum. Many of these tend to produce offsets, so with a little careful digging, it is easy to share.

 

Most Arisaema like at least part shade, but a couple can handle sun. For me, they have all proven easy to grow in normal garden soil, dry or moist. However, persistent wetness will lead to rot. I find they do well in tightly packed competitive conditions. If potted, Arisaema do best in fast draining media that includes a substantial amount of Permatill, sharp stones, pea gravel or even turkey grit.

 

Species worth knowing or growing

 

Southeastern Natives

 

You are likely familiar with our native southeastern woodland jack-in-the-pulpit, Arisaema triphyllum (three-leaved) and its close relative and subspecies Arisaema triphyllum quinatum (five-leaved) as well as Arisaema dracontium (Green Dragon), which bears a distinct horseshoe leaf arrangement. While these are lovely woodland plants, they don't create quite the drama in the garden that some of the Asian species do. Most grow one to two feet tall, are primarily green from any distance and go dormant in the heat of summer.

 

A. triphyllum has one pseudostem topped with two trifoliate leaves. The inflorescences range from green to purple with white stripes, with the rarer purple forms being far more eye-catching. Some naturally occurring and eye-catching variations have been found and vegetatively propagated. These are front of the garden worthy, like A. triphyllum 'Mrs. French's Veins'. 

 

Arisaema triphyllum 'Mrs. French's Veins'

 

 

 

Asian Jack-in-the-Pulpits

 

Arisaema ringens is the gateway drug to collecting jack-in-the-pulpits. As early as February in metro Atlanta, the tips of the pseudostems begin to push up from the earth. In a short course of time, each of those pseudostems will hold two trifoliate leaves (similar to A. triphyllum in number only). These large leaves are a lustrous deep green and bear well defined interior markings. The foliage alone is enough to justify growing A. ringens.

 

The fascinating cobra headed pulpits will soon emerge underneath the leaves. The flowers will wilt in a couple of weeks, but the foliage will continue to grow bigger and wider. It will persist until at least August and sometimes later. There is a purple stemmed cultivar available which provides nice contrast to the foliage, Arisaema ringens 'Black Mamba'. 

 

I grow A. ringens under the dense roots of a red maple, where they thrive and continue to expand. I'm ready to share with friends -- although digging them up might prove daunting. I've also had some grow from dropped seed elsewhere on my property, near where I previously transplanted some offsets. Fully leafed out, A. ringens stands about two feet tall.

 

 

 

Arisaema sikokianum jumps out of the ground in early spring (April) and is blooming size in a week or two. This species definitely requires two to tango (bloom, that is). And what a bloom it is! Many consider A. sikokianum to be the most stunning of jack-in-the-pulpits. It's "jack" or spadix is unique and glows like a beacon. The inflorescence of A. sikokianum is visible from a good distance away and will persist for at least two weeks most years. 

 

 

Arisaema sikokianum

 

 

If you go to the trouble of getting this species, you must get two to bloom. I highly recommend the variegated foliage form (see bottom right of pictures) for landscape interest. The foliage persists well into summer until the heat wilts me too.

 

A. sikokianum also grows well in tight quarters -- under an old densely rooted red maple. In recent years, the mature plants have begun to self sow. It takes two to four years before seedlings might bloom. To date, none of my seedlings have bloomed and the mixture of variegated and non-variegated plants has only produced non-variegated seedlings. Fresh seed in a pot sprouts up fabulously too. A. sikokianum only grows only one to two feet tall, so it is easy to work in near the front of the garden.

 

Some Arisaemas are very slow to emerge and you will think you've lost them if you don't keep  notes or have a great memory. After several years of concern that I'd lost my A. consanguineum 'Silver Center', I've started to call it my "Fourth of July" jack. It may not emerge from the ground until mid to late June, then it will creep up a inch or two a week until it explodes like fireworks by late June or early July. A. consanguineum can easily reach three feet tall or more. Much of this growth happens amazingly fast.

 

Arisaema consanguineum 'Silver Center'

 

A. consanguineum is increasingly being offered with leaf variations, including wider white stripes or drippier tips. The green flower appears six to twelve inches under the leaves making it easier to see than some other species' flowers. It's pretty, but a bit humdrum compared to A. ringens or A. sikokianum. That said, the fun foliage of A. consanguineum persists until frost as do its stunning seed pods (pictured earlier). I grow this one for the foliage not the flower.

 

A. consanguineum has grown for me in nearly full shade (leading to some flopping), part shade (maintaining more erect stems) and this year a volunteer in a container grew beautifully erect in full sun. I often stake the ones in more shade.

 

There is a great deal of variation in A. consanguineum, which can bear fabulous pseudostems that are attractively splotched or just dull green ones. (See below for both.) 

 

Arisaema consanguineum ssp

 

Arisaema candidissimum is an oddity.  Like A. consanguineum, it emerges from the ground late in spring, from late May to early June. If you tag the spot, you might -- like me --  check it daily for signs of life. It will keep you waiting, but not disappoint. It will push up a pseudostem point one day and grow six inches in a week or two.

 

This is one jack that can take some sun and, in fact, does better in it. It is also a small plant, but my, what a looker!  A. candidissimum, unlike many other Arisaema, blooms before it leafs out so the flower can be easily enjoyed. No squatting, bending or turning oneself into a pretzel is required!

 

After the pale pink white-striped flower has nearly expired, rounded trifoliate leaves arise and provide a pleasant green umbrella of foliage about 10" off the ground. A white flowered form is also offered in the trade. This flower does have a light and pleasant fragrance if you are willing to bend down to it.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Arisaema candidissimum

 

 

Arisaema serratum var. mayebarae is valued for its flowers. I've yet to acquire one. The horseshoe-like foliage runs on the coarse looking spectrum to my eyes, but the pulpit is certainly eye catching.

 

Arisaema serratum var. mayebarae

 

I would add Arisaema fargesii before I pursued A. serratum. The flowers bear similar coloration, but the glossy green foliage is rounded and elegant. The foliage, not flowers, is what persists for months lending charm to the garden.

 

A. fargesii

 

There are couple of other jack-in-the-pulpits that are interesting but not "to die for." Arisaema kiushianum is a compact plant. It emerges in March, rising quickly (a trait of most Arisaema). You have to get close to the ground to see the two to three inch high flowers and the very long spadices which grow upward to attract pollinators. (Horticulturists refer to this as a "whipcord".) It is considered an easy to grow form. It's definitely needs to be in front of the border. It might even be better viewed grown in a container. 

 

A. kiushianum

 

Another one worth consideration for both its pretty horseshoe-shaped foliage and a dramatic spadix of 6 to 8 inches is Arisaema saxatile. Growing two to three feet high, it is tall enough to go deeper inside a border, not at the front. The spathes are light green to whitish and Tony Avent says they have a lemony fragrance (which I have never noticed). The whipcords are the fun part of this plant.

 

 

Arisaema saxatile

 

 

 

If you like smaller plants (to 15" tall) and unique colors, then Arisaema flavum might be of interest. I recently acquired one and hope it is bloom size this year or next. This is another Arisaema that not only grows in sun, it prefers some (morning to mid-morning exposure in the south should suffice). The leaves emerge in late spring to early summer, quickly followed by a 1" yellow flower atop the leaves. The inflorescence bears both sexes, so only one plant is needed to make more. 

 

Arisaema flavum

 

 

 

There are many more species of jack-in-the-pulpits out there. They can be pricey, so sharing is a great way to form a collection. 

 

A word of caution about purchasing Arisaemas. I have been sold more than my share of mislabeled Arisaemas by well-regarded horticulturists. Voodoo lily (Sauromatum venosum) came to me as Arisaema taiwanense. Next, a subspecies of Arisaema consanguineum with a similar striped stalk was sold to me as A. taiwanense. After two fails at purchasing that one, I quit trying!  Here is a picture of the elusive A. taiwanense. It bears some similarity to A. consanguineum, except the flower arises from the ground and stays low and is red. The leaves are broader and coarser and the pseudostem is splotched.  This is a tall plant growing from three or more feet high.

 

  Arisaema taiwanense

 

 

Arisaema relatives, lookalikes and misnomers

 

 

Sauromatum venosum is fascinating to observe. The horse-shoe shaped foliage that follows the bloom is attractive and large, worthy enough a reason to grow the plant. Before the leaves emerge, the base of the flower will begin to bulge and swell before pushing up and open to reveal a bloom with a royal looking cloak. It smells awful when it blooms -- to attract the flies that pollinate it -- but the odor is a one day and done event (per bloom) and worth it. Sauromatum venosum reproduces gently nearby and I've begun to share them as they are getting a little too tight knit. After the spathe collapses, the "royal cloak" will persist a week or so longer as if the king inside disappeared leaving behind his coat.

 

 

 

 

 Sauromatum venusom

 

 

 

If you see Pinellia tripartita, P. ternata or other Asian Pinellias at a nursery, you will notice the similarity to Arisaema. Stop yourself now. In our warm climate, they will invade before you blink.  I don't know that I have ever planted and removed a plant for invasiveness concerns faster than Pinellia pedatisecta. There is some breeding ongoing producing sterile Pinellias.That said, to my mind, even the prettiest of them don't rival most of the Asian Arisaemas.

 

Piniella pedatisecta

 

 

Contributed by Liane Schleifer