Aside from the corn plants that produce ears of corn for human and animal food, a corn plant is also a species of flowering plant known as Dracaena fragrans. Cultivars of this member of the Agave family, Agavaceae, are widely grown as office plants and houseplants. Native to western Africa, they are also grown as ornamentals in tropical climates. The plants are very low maintenance, which accounts for a great deal of their popularity.
Corn plants grown in a tropical climate can reach 20 feet (6 m) tall, although they grow slowly. The leaves can reach 3 feet (0.9 m) long. Dracaena fragrans has its name because the plants occasionally produce sweet-smelling flowers that open at night. Houseplants generally do not produce the flowers.
In the wild, the plants typically produce trees with clumping stems or multiple trunks. Corn plants can be grown with a single stem, however. In cultivation, this species spreads 2 to 3 ft (0.6 to 0.9 m). Individual plants should be planted 1.5 to 2 feet (0.45-0.6 m) apart.
A corn plant is a relatively undemanding landscape plant, as long as it is grown in the shade and is not subjected to ocean salt in the soil. One care factor is paramount however — corn plants should not be over-watered, as they can succumb to fatal attacks of root rot. The plant is tolerant of a wide range of soil types.
As a houseplant, the corn plant also does not require a great deal of care. When kept indoors, it does not grow anywhere near as large as the plants do in the tropics. The cultivar most commonly grown indoors is called Massangeana, which has a bright yellow stripe down the center of the leaf. The leaves of these plants resemble sweet corn, giving the common name to this species. This cultivar typically grows to 5 feet (1.5 m) tall when grown indoors.
This type of plant can grow well in either low or medium light, depending on the source. They should not receive direct light, such as sunlight, however. They flourish in artificial environments, such as offices lit by fluorescent lights.
These specimens grow best when kept constantly moist. These plants are very sensitive to fluoride, which is often a component in municipal water. Also, superphosphate fertilizer should be avoided, since it contains high levels of this compound. Keeping the soil pH at between 6.0 and 6.5 will help protect against fluoride-induced injury.
The corn plant grows well when temperatures are warm, such as 75° to 85°F (23.9° to 29.4°C) during the day, and 65° and 70°F (18.3° and 21.1°C) at night. It is important to have a drop in temperature during the night. The plants should be fertilized monthly during the periods of active growth, usually spring and summer.
If one grows too high or the stems become too barren, the corn plant can be cut back. New leaves will typically grow rapidly. Propagation can be by cuttings of the stem or tip, air layering, or removing and planting shoots from its base.