Plant of the Week
Jack-in-The-Pulpit (Arisaema triphyllum)
By Jan Schultz
Jack-in-the-pulpit, also commonly called Indian turnip, is a shade requiring species found in rich, moist, deciduous woods and floodplains. A long lived perennial (25+ years), it will spread and colonize over time from an acidic corm.
The Arum family (Araceae), of which it is a member, contains 27 genera and six other species within the genus Arisaema. All species -A. dracontium/ green dragon, A. speciosum/ cobra lily, / A. japonica/ Japanese arisaema, / A. heterophyllum/ A. tortuosum/ arisaema - possess the characteristic and exotic flower structures. Jack-in-the pulpit is pollinated by small flies and flowers from March through June depending on locale. The flower is an unusual green and maroon striped spathe surrounding a fleshy, maroon-colored spadix that bears the tiny, embedded flowers. The showy, bright red berries have the consistency of a ripe tomato, and are an attractive food source for birds such as thrushes, rodents, etc. Each berry contains 1 to 5 seeds and ripens in the fall. The unusual flowers, attractive 3-parted leaves, and showy fruits make this species an attractive addition to a shady native plant garden.
Leaves and fruits contain calcium oxalate that can irritate the skin so it is important to wear gloves when collecting and cleaning the berries. Seeds should be cleaned as soon as possible after collection as they are recalcitrant and lose viability if allowed to dry out. Berries can be smashed with a large spoon or by hand, and the seeds separated by rinsing them in a strainer, picking out large debris. Following cleaning, seeds should be immediately place into cold moist stratification for 60 to 90 days by mixing them with an equal part of moist perlite and placing the mixture into a Ziploc-style bag or a Rubbermaid style container. Anecdotally, it has been observed that the ripe berries can be tossed directly on to the soil of a restoration site with high rates of germination resulting the following spring. During the first growing season seedlings form a small corm and one or two whorls of leaves. Seedlings need to be handled carefully during extraction from containers as the seedling only produces a corm, not a root-tight plug.
For More Information
- PLANTS Profile - Arisaema triphyllum, Jack-in-The-Pulpit
- Propagation protocol for Jack-in-the-Pulpit (Arisaema triphyllum) - a Native Plants Journal Article