Practical
Plants

Yucca rupicola

Twisted-Leaf Yucca

No photo available

Taxonomy and growth

Family
Agavaceae
Genus
Yucca
Life cycle
perennial
Foliage
evergreen
Woodiness
woody
Height
0.6 m
Fertility
Hand
Flower type
hermaphrodite
Pollinators
Hand

Uses

Toxicity

Toxicity warning. The historical record reports a hazard for this plant. Do not use it to decide which parts are safe to eat or use medicinally.

The roots contain saponins[5]. 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[K]. 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[K].

Edible uses

Fruit - raw or cooked. Flowers - raw or cooked. They are delicious raw, and can also be dried, crushed and used as a flavouring[2]. Flowering stem - cooked and used like asparagus[2].

Plant part
Flowers
Plant part
Fruit
Plant part
Stem

Material uses

A fibre obtained from the leaves is used for making ropes, baskets and mats[82. 169]. The roots are rich in saponins and can be used as a soap substitute[9].

Product or use
Fibre
Product or use
Soap

Environment

Range
Southern N. America - Texas.
Habitat
Limestone ledges and plains[7].
Light
full sun
Shade tolerance
light shade
Water
moderate
Hardiness
Zone 9+
Soil textures
sandy, loamy, clay
Soil pH
acid, neutral, alkaline
Drainage
well drained
Tolerances
high wind, drought
Wind
Yes
Tolerates Nutritionally Poor Soil
No
Drought
tolerant

Propagation

Seed - sow spring in a greenhouse. Pre-soaking the seed for 24 hours in warm water may reduce the germination time. It usually germinates within 1 - 12 months if kept at a temperature of 20°c. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse or cold frame for at least their first two winters. Plant them out into their permanent positions in early summer and consider giving them some winter protection for at least their first winter outdoors - a simple pane of glass is usually sufficient[K]. Seed is not produced in Britain unless the flowers are hand pollinated. Root cuttings in late winter or early spring. Lift in April/May and remove small buds from base of stem and rhizomes. Dip in dry wood ashes to stop any bleeding and plant in a sandy soil in pots in a greenhouse until established[8].

Cultivation

Thrives in any soil but prefers a sandy loam and full exposure to the south[1]. It can succeed in light shade[K]. Plants are hardier when grown on poor sandy soils[4]. Established plants are very drought tolerant[4]. Hardy to at least -5°c[4], plants have succeeded outdoors in the drier areas of Britain[3]. It flowers regularly outdoors in Scotland[1]. 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[6]. However, the crown will usually produce a number of sideshoots before it dies and these will grow on to flower in later years[6]. Plants in this genus are notably resistant to honey fungus[4]. Members of this genus seem to be immune to the predations of rabbits[6]

References

  1. Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981-00-00

    ↩1↩2

  2. Bird. R. (Editor) Growing from Seed. Volume 4. Thompson and Morgan. 1990-00-00

    ↩1↩2

  3. Thomas. G. S. Ornamental Shrubs, Climbers and Bamboos. Murray 1992-00-00 ISBN 0-7195-5043-2

    ↩

  4. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

    ↩1↩2↩3↩4

  5. Foster. S. & Duke. J. A. A Field Guide to Medicinal Plants. Eastern and Central N. America. Houghton Mifflin Co. 1990-00-00 ISBN 0395467225

    ↩

  6. Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. 1990-00-00 ISBN 0 460 86048 8

    ↩1↩2↩3

  7. Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J Illustrated Flora of North Central Texas Botanical Research Institute, Texas. 1999-00-00 http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm

    ↩

  8. Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948-00-00

    ↩

  9. Sargent. C. S. Manual of the Trees of N. America. Dover Publications Inc. New York. 1965-00-00 ISBN 0-486-20278-X

    ↩

Edit this page