Yucca rupicola

Scheele

Twisted-leaf yucca

Asparagaceae Edible: Flowers, Fruit, Stem Potential hazards — see below 9,304 iNaturalist observations

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Summary

Yucca rupicola is a plant in the family Asparagaceae, known as the twistleaf yucca, twisted-leaf yucca, Texas yucca or twisted-leaf Spanish-dagger. The species was described by George Heinrich Adolf Scheele in 1850. This is a small, acaulescent plant with distinctive twisted leaves. It is native to the Edwards Plateau region of Texas and also to northeastern Mexico (Coahuila, Nuevo León). Yucca rupicola forms colonies of rosettes, lacking trunks above-ground but producing a branched caudex under the surface. Leaves are narrowly lanceolate, slightly succulent, twisted, up to 60 cm long but about 40 mm wide at its widest point. Flowers are pendant (drooping), bell-shaped, white or greenish. Fruit is a dry capsule up to 6 cm long.

Description

A shrub without a stem and with a ring of spiny leaves. The leaves are sword shaped and twisted. They are 35-60 cm long by 1.4-7 cm wide. They are widest near the middle and are fleshy. The flowers hang down. They are white or greenish. The fruit are erect and cylinder shaped. They are 4-5.5 cm long. The seeds are dull black and 6-8 mm across.

Edible Uses

The fruit can be eaten raw or cooked. Flowers are delicious raw and can also be dried, crushed and used as a flavouring. The flowering stem is cooked and used like asparagus.

Traditional Uses

The flowers can be eaten raw or cooked. They can also be dried and crushed and used as flavouring.

This uses section is brief — help expand it

Medicinal Uses

None known.

Known Hazards

The roots contain saponins. Whilst saponins are quite toxic to people, they are poorly absorbed by the body and so tend to pass straight through. They are also destroyed by prolonged heat, such as slow baking in an oven. Saponins are found in many common foods such as beans. Saponins are much more toxic to some creatures, such as fish, and hunting tribes have traditionally put large quantities of them in streams, lakes etc in order to stupefy or kill the fish.

Distribution

It is a temperate plant.

Where It Grows

North America, USA,

Cultivation

Thrives in any soil but prefers a sandy loam and full exposure to the south. It can succeed in light shade. Plants are hardier when grown on poor sandy soils. Established plants are very drought tolerant. Hardy to at least -5°c, plants have succeeded outdoors in the drier areas of Britain. It flowers regularly outdoors in Scotland. In the plants native environment, its flowers can only be pollinated by a certain species of moth. This moth cannot live in Britain and, if fruit and seed is required, hand pollination is necessary. This can be quite easily and successfully done using something like a small paint brush. Individual crowns are monocarpic, dying after flowering. However, the crown will usually produce a number of sideshoots before it dies and these will grow on to flower in later years. Plants in this genus are notably resistant to honey fungus. Members of this genus seem to be immune to the predations of rabbits

Propagation

Sow seed in spring in a greenhouse; pre-soaking for 24 hours in warm water may speed germination. Seed typically germinates within 1–12 months at 20°C. Prick seedlings into individual pots and grow on under glass for at least their first two winters. Plant out in early summer with winter protection — a pane of glass usually suffices — for at least the first outdoor winter. In Britain, seed is only produced with hand pollination. For root cuttings, lift in April/May, remove small buds from the base of stem and rhizomes, dip in dry wood ash to prevent bleeding, and pot in sandy soil in a greenhouse until established.