Yucca rigida - M

About the Yucca rigida - M

Yucca rigida is a slow-growing, evergreen and trunk-forming yucca from northern Mexico. The species develops a dense, almost spherical rosette of rigid blue-grey to silver-blue leaves. Its symmetrical growth habit and striking foliage colour make it a distinctive architectural plant for a sunny, dry outdoor space. Commercial size M does not establish the age, existing trunk height or flowering maturity of the supplied plant.

Characteristics

Origin: Yucca rigida is the familiar and internationally used horticultural name for this plant. Botanically, the name is currently also treated as a synonym of Yucca luminosa. The species is native to northern Mexico, particularly parts of the Chihuahuan Desert in Chihuahua, Durango and Coahuila, where it grows in dry landscapes on stony and calcareous soils.

Family: Asparagaceae, the asparagus family.

Position: Suitable for a warm, sunny outdoor position, either in a large container or in the ground in a very well-drained and preferably sheltered location. Full sun supports compact growth and a pronounced blue foliage colour. Avoid low-lying areas where rainwater can collect.

Height: A mature plant can reach approximately 3 to 4.5 metres in height and 1.5 to 3 metres in width under suitable conditions. Older plants develop an upright trunk that can eventually branch several times. Growth is slower in a container and the ultimate size generally remains more restricted.

Flowering period: Mature plants can flower in late spring or early summer. The precise flowering period depends on the climate and growing conditions. The supplied plant in size M is not necessarily mature enough to flower.

Flower colour: Creamy white to white, bell-shaped flowers that appear on mature plants in a large, branched inflorescence between or above the leaves.

Hardiness: A well-established plant can tolerate short periods of frost around -15°C in dry soil and a sheltered position. Wet winter soil and prolonged frost significantly increase the risk of damage. Protect size M, particularly when grown in a container, when temperatures below -5°C are expected. Keep the root ball as dry as possible during cold periods without allowing it to remain completely dry for a prolonged time.

Soil type: Use a very airy, mineral-rich and rapidly draining soil, preferably with a neutral to alkaline reaction. Combine potting soil with a generous proportion of coarse sand, lava grit, pumice or fine gravel. Avoid heavy, humus-rich soil in which water remains around the roots.

Care

Light: Provide Yucca rigida with as much direct sunlight as possible. Gradually acclimatise a plant coming from a greenhouse or sheltered winter position to strong sunlight to prevent leaf scorch.

Water: Water moderately during the growing season and allow the soil to dry substantially between waterings. Moisten the root ball evenly and allow excess water to drain away completely. Water a container-grown plant slightly more often during hot, dry periods. Reduce watering significantly in winter and prevent the root ball from remaining wet for prolonged periods.

Fertiliser: Apply one modest dose of suitable fertiliser for yuccas, cacti or other drought-tolerant plants in spring. Do not exceed the recommended dosage. Heavy feeding can produce weaker growth and is unnecessary for this slow-growing species.

Pruning: Remove only fully dried or severely damaged leaves and spent inflorescences. Cut the leaves close to the trunk without damaging healthy trunk tissue or the central growing point. Wear sturdy gloves and eye protection because of the sharp leaf tips.

Repotting: Repot preferably in spring when the roots have largely filled the available container or when the plant becomes unstable. Choose a heavy, stable pot only one size larger with several generous drainage holes. Use a mineral and rapidly draining substrate and do not plant the base of the trunk deeper than before.

Humidity: Low to average humidity with plenty of air circulation is suitable. Misting the leaves is unnecessary and may cause the foliage to remain wet for longer during cool weather.

Special features: The rigid, powder-blue leaves end in sharp points and can cause injury. Keep the plant away from narrow walkways, play areas and frequently used terraces. Older leaves may bend downwards and remain around the trunk as a natural skirt. Yucca rigida grows slowly but can eventually develop into a striking, branched specimen plant.