Common Name: rattlesnake plant
Type: Herbaceous perennial
Family: Marantaceae
Native Range: Brazil
Zone: 11 to 12
Height: 0.75 to 1.50 feet
Spread: 0.75 to 1.50 feet
Bloom Time: Seasonal bloomer
Bloom Description: Yellow
Sun: Part shade to full shade
Water: Medium
Maintenance: Medium
Flower: Showy
Leaf: Colorful, Evergreen
Other: Winter Interest
Culture
With good humidity, consistent soil moisture, warm air temperature, and an absence of direct sun, this tropical perennial will usually develop into an extremely attractive indoor foliage plant. Best indoor container growth typically occurs in uniformly moist, well-drained, peaty potting mixtures in room temperatures ranging from 65-75°F in limited sun to bright shade locations. Avoid full sun, particularly in the heat of the afternoon. Tolerates some early morning sun or diffused sun. Avoid drafts or sudden temperature changes. Plants need high humidity which can often be difficult to provide in winter. Consider standing a potted plant on a bed of wet pebbles, misting the foliage regularly and/or growing the plant in a humidified room. During the growing season (April-August), water regularly to keep soils moist (but not wet) and apply a balanced fertilizer monthly. Reduce watering and fertilization in winter when plant growth typically slows down. Propagate by division.
Noteworthy Characteristics
Calathea lancifolia, commonly known as rattlesnake plant, is a rhizomatous tropical evergreen perennial that it winter hardy to USDA Zones 11-12. It is native to Brazilian rainforests. Although it may be grown outdoors at the far southern edges of Florida and California plus Hawaii, it is otherwise grown indoors in the remaining parts of the U. S. for appreciation of its ornately patterned foliage. Flowers rarely appear on indoor plants. Plants typically grow to 1 1/2’ tall indoors, but rise to 2 1/2’ tall outdoors. Wavy-margined linear to lanceolate leaf blades (each to 18” long) are pale green to yellow-green above variegated with (a) attractive dark green elliptic blotches on both sides of the midrib, (b) thin dark olive green marginal edge, and (c) reddish purple to maroon undersides. The markings on each leaf purportedly resemble the markings found on some rattlesnakes, hence the common name for this plant. On plants grown outdoors, yellow flowers bloom seasonally, but typically from late spring to early summer in 2-4” long conical spikes.
In the tropics, this plant is commonly grown outdoors in shaded areas and courtyards for display of its highly ornamental foliage.
Genus name comes from the Latin word calathus meaning basket in reference to the inflorescence looking like a basket of flowers.
Specific epithet means lance-leaved in reference to the lance-shaped leaves.
Problems
Watch for aphids, scale, mealybugs and spider mites. Leaf spots may appear. Plants do not thrive in low humidity where leaves may roll or brown up. Direct sun usually causes leaf scorch.
Uses
This plant is grown for its attractive foliage. Houseplant for bright areas with no direct sun. Popular landscape plant in Hawaii.