Pachystachys coccinea
Common Name: cardinal's guard 
Type: Broadleaf evergreen
Family: Acanthaceae
Native Range: West Indies, northern South America
Zone: 10 to 11
Height: 1.00 to 2.00 feet
Spread: 1.00 to 3.00 feet
Bloom Time: Seasonal bloomer
Bloom Description: Scarlet red
Sun: Full sun
Water: Medium
Maintenance: Medium
Suggested Use: Annual
Flower: Showy
Leaf: Evergreen

Culture

Winter hardy to USDA Zones 10-11. In St. Louis, grow in the garden as a summer annual, in containers that can be overwintered indoors or as a year round houseplant. In the ground, plants need a consistently moist, organically rich, well-drained soil in full sun. Tolerates part shade. Plants thrive in humid summers. Best growth occurs with continuous and even moisture. Do not allow soils to dry out. Reduce watering in winter. Houseplants are best in warm, humid, sunny locations. Overwinter plants in cool areas (not less than 65 degrees F.) in front of a sunny window with reduced watering.

Noteworthy Characteristics

Pachystachys coccinea, commonly called cardinal's guard, is native to the West Indies and tropical areas of South America. It is an erect, evergreen shrub or sub-shrub that grows 2-6’ tall in its native habitat. When grown in containers in the St. Louis area, it grows much shorter. Narrow, tubular, two-lipped, bright scarlet flowers bloom on green-bracted terminal spikes. Although it blooms throughout the year in its native habitat, cardinal's guard blooms primarily in summer when grown in the St. Louis area. Ovate-elliptic dark green leaves (to 6” long).

Genus name comes from the Greek words pachys meaning thick and stachys meaning ear of corn or spike in reference to the dense flower clusters.

Specific epithet comes from Latin meaning scarlet in reference to flower color.

Problems

No serious insect or disease problems. Watch for aphids, whiteflies and spider mites, particularly on indoor plants.

Garden Uses

Summer annual. Container. Houseplant. Greenhouse plant.