Yucca aloifolia flowers
A genus of about 40 species of perennial evergreen shrubs or trees, Yucca is rosette-forming or woody- based and comes from hot, dry places such as deserts. sand dunes and plains in north and central America and the West Indies. It is also colloquially known in the Midwest United States as “ghosts in the graveyard”, as it is commonly found growing in rural graveyards and when in bloom the cluster of (usually pale) flowers on a thin stalk appear as floating apparitions. So striking are these flowers that early settlers of the south-western United States called them “Lamparas de Dios” or “Lanterns of God”.
A member of the Agavae family, the yucca is closely related to the lily and has its origins in Mexico and Central America where it was prized by indigenous peoples for the medicinal and nutritional properties of the yucca flower.
North American natives, too, found the plant useful, using it to make clothing and soap (yucca roots are rich in saponins).
Cultivated for their bold, linear to lance shaped leaves and their erect (sometimes pendent) panicles of, usually white bell-shaped flowers. Many species also bear edible parts, including fruits, seeds,flowers, flowering stems and more rarely roots. References to yucca root as food often stem from confusion with the similarly pronounced, but botanically unrelated, yuca, also called cassava (Manihot esculenta).
They tolerate a range of conditions, but are best grown in full sun in subtropical or mild temperate areas. In gardening centres and horticultural catalogues they are usually grouped with other architectural plants such as Cordylines and Phormiums.
Joshua Tree at Grapevine Springs Ranch, Arizona
Y. brevifolia flower
Joshua trees
(Yucca brevifolia) are protected by law in some American states. A permit is needed for wild collection. As a landscape plant, they can be killed by excessive water during their summer dormant phase, so are avoided by landscape contractors.
Several species of yucca can be grown outdoors in mild temperate climates where they are protected from frost. These include:-
Y. filamentosa
Y. flaccida
Y. gloriosa
y. recurvifolia
 Y. filamentosa  Y. flaccida  Y. gloriosa |
Yuccas are widely grown as architectural plants providing a dramatic accent to landscape design. They can be used as specimen plants in courtyards or borders and in frost prone areas can be grown in a cool or temperate greenhouse or conservatory. Pollination and proper yucca care are necessary for the formation of these flowers on indoor plants.
Be careful to site them away from paths or other places people could be scratched by their sharp leaves. Free-draining soil and sun is all yuccas require.They are fully frost hardy to frost tender and can be propagated by seed sown in spring. Rooted suckers can also be removed in spring and root cuttings can be taken in the autumn. They can be susceptible to leaf spot and aphid attack.
Yucca guatemalensis (syn Yucca elephantipes)
Old School Garden 