Family: Asparagaceae
Common name: Giant yucca, Spineless yucca, Soft tipped yucca, Yucca cane, Blue-stemmed yucca
Giant Yucca is a striking, large, eye-catching shrub that is grown as an ornamental plant in countries with hot, semi-arid climate.
They are native to Southwestern United States and Mexico, but they are now grown in multiple countries, loved for their sculpture-like stems and spiky, sword-like leaves.
Plant Characteristics
Giant Yucca plants grow to a height of 8-10 meters with woody, strong, thick, tree-like stems. Younger plants look like a rosette of leaves on the ground, the stems or mini-trunks appearing as the plant grows older and taller.
The central stem is straight, sometimes single, and sometimes branched with a tuft of leaves on top, like a mop.
Yucca plants have a fibrous root system that helps the plants anchor itself to the soil, while absorbing water and nutrients from deep underground. The stems have circles around them like growth rings, where the leaves have fallen off and left a scar.
The thick stems help the Giant Yucca plants to store and conduct water, and also to support the weight of the foliage and flowers.
Leaves of the Giant Yucca are long, slender, and sword-shaped but without the spines that are typical of other Yucca, giving the plant its name Soft-tipped yucca or Spineless yucca. Leaves are 80-90 cm long, greenish-grey or blue-green in color with a pointy tip.
They are thick and leathery with a smooth margin and waxy coating on the surface to help conserve water in the arid conditions, the plants usually grow in. The lack of thorns makes them easy to handle and hence are excellent for home gardens, parks, or urban landscaped areas for a unique, desert-like vibe.
Giant Yucca flowers appear in large clusters of white or pale yellow, bell-shaped blooms. They usually bloom during the summer months, around June to August. Each cluster contains over 30 flowers held aloft of tall flower spikes that are about 2 meters tall.
Flowering does not happen regularly and hence these plants are mostly grown for their beautiful foliage and growing habit. Giant Yucca flowers are fragrant and stay open for a long time, attracting diurnal and nocturnal pollinators like small birds, bees, insects, butterflies, moths, and bats.
After pollination, the flowers produce small fruits that are elongated and roughly cylindrical, that contain numerous black seeds. Fruits are initially green, later turning yellow and then brown as they mature. The fruits or seeds are not eaten by humans, but make a good food source for other small animals.
Gardening Tips
Giant Yucca plants grow well in good sunlight and hot, arid, desert-like weather. They need well-drained soil and highly controlled watering since overwatering can affect the plant much more than underwatering.
Soil should be loamy and well-draining, grown in cactus and succulent mix with a lot of perlite and cocopeat. Giant Yucca plants are very drought-tolerant and should be watered only during peak summer season, and when the soil is completely dry.
Since Yucca plants grow slowly, they do not need regular fertilization, but just once or twice a year during spring and summer.
Pruning is a personal choice when it comes to Yucca. There are people who remove the dead, dry leaves so that the stems are visible, and there are those who let them stay on the plant.
In their natural habitat, these dead leaves bend down fully covering the stem, helping in conserving water. So it is best to leave them as a covering for the stem. However, in areas where the plants are watered and tended to, these leaves can be removed to bring out the structural quality of the Giant Yucca.
Giant Yucca are closely related to Yucca aloifolia or Aloe yucca, which is a smaller plant with thinner, more pointy leaves.
Uses of Giant Yucca
Giant Yucca plants are usually grown as ornamental plants for their thick, woody stems and large rosettes of leaves. The flowers were eaten in different ways by various tribes in Central and South America. But they have a slight bitterness, which can be avoided by eating only the petals.
The petals of the flowers are eaten raw, blanched, or cooked, and used in soups, salads, stews, and stir-fries. Tender leaf bases are also edible, though they are not widely eaten.
Fiber obtained from the bark and leaves is quite strong, used for making baskets, cloth, and twine.
Giant Yuccas make excellent xeriscaping plants since they are tolerant of drought and hot weather.
Propagation of Yucca gigantea
Propagation is through seeds and stem cuttings.
Since flowering and fruiting is not an annual process, it is more difficult to propagate these plants through seeds. Mature seeds taken from the fruits can be soaked in water for a day to improve the speed of germination.
Stem cuttings about 15-20 cm long should be allowed to dry for a few days before planting them in moist, well-draining soil. Patience is the key to growing Giant Yucca since they are very slow growers.
Photographed at: Bharatiya City, Bangalore
