Yucca gigantea

The giant yucca or spineless yucca is a tropical perennial grown for its stunning foliage. It is a popular, low-maintenance indoor and outdoor plant that presents as a large, upright succulent shrub or small tree. It is native to Central America and is a member of the asparagus family (Asparagaceae). Unlike other species of Yucca, this plant does not have sharp, spine-tipped leaves. It was formerly known as Yucca elephantipes, whose specific epithet referred to the plant's thick trunk that resembles an elephant's foot. Outdoors, this plant can grow up to 15 to 30 feet tall and 15 to 25 feet wide. If grown as a houseplant, it will be much more compact. 

The giant yucca prefers full sun, and moist, well-drained, loam and sandy soil. For houseplants, one part potting mix and 3 parts perlite or sand is recommended to provide good drainage. This plant is drought tolerant, and overwatering can be problematic. Indoor temperatures and humidity levels are adequate for this plant but keep it away from cold drafts or sudden temperature changes. When grown outdoors, it thrives in warm climates with temperatures between 70 to 90 degrees Fahrenheit. The plant is winter hardy in USDA hardiness zones 10 to 12.  It will need to be brought indoors when the temperature drops below 50 degrees Fahrenheit. Cold and freezing temperatures can lead to plant damage and dieback. This plant can be propagated by seeds, cuttings, and from suckers found at the base of the tree or shrub.

The giant yucca has evergreen, smooth, spineless, leathery, stiff leaves that are pale green to blue-green, linear or lanceolate with soft tips. The leaves are arranged in spiral rosettes and can measure 12 to 18 inches long. The flowers bloom in late spring or summer and are creamy-white and bell-shaped that present in clusters on tall stalks. The fruit is oval, fleshy, and brown and does not appear to attract wildlife. The trunk of the plant is thick and woody. 

The giant yucca can be used in the garden or indoors. It can be used as a container plant on a patio or planted in beds or borders for a coastal or tropical appearance. Indoors, this plant's striking vertical structure is a perfect accent for your home. 

Insects, Diseases, and Other Plant Problems:  The giant yucca is generally free of insects and diseases. Monitor for mealybugs, aphids, scale, black weevil, and yucca moth borers. Overwatering can cause root rot.  Avoid planting near foundations due to its massive base. As the plant matures, it will be very difficult to remove. The leaves and roots are toxic to humans, cats, dogs, and horses.