Type: Herbaceous perennial
Family: Araceae
Zone: 5 to 9
Height: 3.00 to 4.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: April
Bloom Description: Green and purple spathe with white stripes
Sun: Part shade to full shade
Water: Medium to wet
Maintenance: Medium
Suggested Use: Rain Garden
Flower: Showy
Fruit: Showy
Tolerate: Heavy Shade
Culture
Best grown in humus-rich, moist but well-drained soils in part shade to full shade. Needs consistent moisture. Does poorly in heavy clay soils. Plant tubers about 3-4" deep. May be grown from seed, but may take 3-5 years before plants will flower.
Noteworthy Characteristics
Arisaema angustatum var. peninsulae is a tuberous woodland perennial that is native to Japan. It is closely related to the Jack-in-the-pulpit that is native to eastern North America (Arisaema triphyllum). It typically grows to 3-4' tall. Each tuber produces a single mottled stem containing two pedate leaves, each bearing 7-20 obovate to lanceolate leaflets (to 2-5" long). From the center of the leaf stalks rises a flower in spring. Each flower consists of a showy spathe (to 4-6" tall) with a hood that covers the inner upright yellow-green flower spike known as the spadix. Spathe is green or purple with white stripes. Plants go dormant in summer after flowering, except hermaphroditic flowering plants will produce a cluster of red berries in mid to late summer which become visible as the spathe withers. Stalks, leaves, flowers and fruits give this plant a tropical aura. Roots contain calcium oxalate (same chemical as in Diffenbachia or dumb cane) and are poisonous.
Some authorities consider this plant to be synonymous with Arisaema serratum.
Genus name comes from Greek words aris meaning "arum" and aima meaning "red", in reference to the red-blotched leaves found on some species.
Specific epithet means narrowed.
Problems
No serious insect or disease problems.
Uses
Plant in groups. Best left undisturbed in shady woodland gardens, wild gardens or native plant areas.