Yucca periculosa - M

About the Yucca periculosa - M

Yucca periculosa is an evergreen, tree-forming yucca with a bold, architectural appearance. The species forms sturdy rosettes of long, green, sword-shaped leaves with coarse, curling fibres along the leaf margins and a sharp terminal point. On mature plants, the leaves may reach approximately 50 to 70 centimetres in length. Older specimens can develop a substantial trunk and a branched crown bearing multiple rosettes. In size M, this yucca is suitable as a striking outdoor plant in a sturdy container on a sunny patio or for a warm, very well-drained position in the garden. Size M is a commercial sales size and does not in itself provide information about age, current height, trunk formation, number of rosettes, degree of rooting or flowering maturity.

Characteristics

Origin: Yucca periculosa is native exclusively to Mexico and is known from Oaxaca, Puebla, Tlaxcala and Veracruz. It grows there in dry scrub and transitional areas of seasonally dry vegetation, including on stony, calcareous soils and at elevations of approximately 1,500 to 2,500 metres.

Family: Asparagaceae, the asparagus family.

Position: Yucca periculosa is an outdoor plant. Choose a sunny, warm and airy position where rainwater can drain away quickly. A raised or sloping site is safest when planted in the ground. Above all, protect the plant from persistently wet winter soil and do not place a container-grown specimen in a saucer where water can accumulate.

Height: In its natural habitat, the species may eventually reach approximately 10 metres in height; exceptional specimens have been reported at up to around 15 metres. On older plants, the trunk often begins to branch at some height and then supports multiple rosettes. In a container and a temperate climate, this development is generally much slower and the plant remains smaller for longer. Size M does not indicate current or future plant height or trunk formation.

Flowering period: Sufficiently mature plants may flower in spring and early summer. In the natural range, flowering has mainly been recorded from March to May; cultivated plants may continue flowering into July. The precise timing depends on climate, position and development. Size M does not indicate that the plant has already reached flowering maturity.

Flower colour: The pendent, bell-shaped flowers are whitish to creamy white and may sometimes have a purplish tint. They are held in a large, branched inflorescence that emerges among the leaves of mature plants.

Hardiness: The species grows locally at high elevations and tolerates some frost in dry conditions, but a reliable universal minimum temperature has not been established. Wet soil, prolonged frost, cold winds and container cultivation increase the risk of damage. As size M does not guarantee a particular degree of rooting, protection from approximately -5 °C is a safe precaution. Insulate the container and prevent the root ball from remaining frozen or wet for prolonged periods.

Soil type: Use a mineral-rich and very well-drained soil. Sandy, gravelly, stony or calcareous soil is suitable. Improve heavy clay soil generously with mineral material and preferably plant in a raised position. In a container, use an airy cactus or succulent growing medium with additional grit and ample drainage holes.

Care

Light: Full sun is the best choice. Gradually acclimatise a plant coming from a sheltered greenhouse or less brightly lit environment to intense direct sunlight to prevent foliage damage.

Water: Water a newly planted yucca and a container-grown specimen during the growing season once the growing medium has largely dried. Then moisten the entire root ball and allow all excess water to drain away. A well-established specimen is drought tolerant. Water sparingly in winter and never allow the plant to remain in wet soil for prolonged periods.

Fertiliser: Yucca periculosa requires little feeding. If necessary, apply a suitable cactus or succulent fertiliser sparingly during active growth, following the recommended dosage on the packaging. Avoid overfeeding and nitrogen-rich fertilisers, as these may encourage overly soft growth.

Pruning: Formative pruning is generally unnecessary. Remove only completely dead or severely damaged leaves and cut back a spent flower stalk once it has fully died. Old leaves may naturally remain hanging around the trunk. Do not damage the central growing points, and wear sturdy gloves and eye protection because of the sharp leaf points.

Repotting: Preferably repot in spring when the roots clearly fill the container, the growing medium loses its structure or the plant becomes unstable. Choose a sturdy container that is only slightly larger and has ample drainage holes, and disturb the root ball as little as possible. Do not position the plant more deeply than before after repotting.

Humidity: Low to normal humidity with free air circulation is suitable. The plant does not require increased humidity. Avoid a persistently humid, poorly ventilated environment, especially in combination with low temperatures.

Special features: The leaves end in sharp points and may cause injury. Position the plant away from paths, seating areas and places where children or pets play. Sufficiently mature plants may develop large, pendent fruits after successful pollination. Both the flowers and fruits are documented as edible, but size M does not guarantee flowering or fruit production.