UF/IFAS Okeechobee County Extension Service

458 Highway 98 North

Okeechobee, FL 34972-2578

Phone: (863) 763-6469

E- mail:  dfculbert@ifas.ufl.edu

July 27, 2005

Feature Article - for release the week of July 31, 2005

Dan Culbert - Extension Horticulture Agent

Yucca produces National Flower

 

 

I often receive emails from far away places with interesting requests for assistance.  A Miami high school teacher sent me a message while she was visiting Guatemala this summer, asking where she could find a particular plant that grows edible flowers.  All I had to go on was the central American name for this plant -  Flor de izote.

 

After some searching and some translation, it turns out the plant she was seeking does grow in our area, and not only is it an ornamental adapted to local conditions, but its flowers are the national flower of the country of El Salvador. We know it is yucca – the subject of this week’s column.

There are as many as 56 different species of yucca found growing in North America , with many native to the drier, warmer climates of the desert southwest.  However, only a few species are found in Florida Yards, and can even be used as foliage plants in our homes. 

Yuccas have thick fleshy stems with broad stiff thickened leaves that may be tipped with a sharp spine.  The leaves give us the common names of locally used plants: Spanish Bayonet, Spanish Dagger, Adams Needle and the most desirable ornamental, Spineless Yucca. The Spineless yucca was introduced into Florida in 1956; its softer leaf-tips make it more desirable in homes and landscapes where the leaf tip would be a safety hazard.

 

In the summer through fall, a two to three-foot-tall flower spike grows at the top ends of the stems once the plant reaches a certain height or grows for a certain amount of time, depending on the species. These flower spikes are covered with fragrant white, bell-shaped flowers. 

 

These are the “flor de izote”, or yucca flowers that are considered a delicacy in some Central American countries.  Blooms are edible and high in calcium and potassium and can be used in salads.  I’d note that the starchy yucca side dish found in Hispanic restaurants is made from the roots of a different plant. I’d caution using other parts of yucca for human consumption, as some species contain large amounts of saponin, a soap producing compound.

 

 

Spanish Bayonet (Yucca aloifolia) is a native of dry, sandy soils, and can have a good use as a “burglar bush” because of the sharp spines.  It makes a dramatic landscape statement with its dark green, stiff, dagger-like leaves projecting from thick, inclining trunks.  White blossoms appear in springtime to late summer in the center of the plant above the foliage. If the sharp needled tips are removed with shears, Spanish Bayonet makes a wonderful accent at entryways or in a shrub border. Their striking texture adds an accent to any Florida Yard.  Plants eventually form attractive, multi-stemmed clumps.  High salt tolerance makes Spanish Bayonet ideal for seaside plantings. A cultivar ‘Tricolor’ has green and white leaves.

 

Spanish Dagger (Y. gloriosa) may be confused with Spanish Bayonet.  The edges of the leaves on Spanish Dagger are smooth, while those on Spanish Bayonet are rough. The outer halves of the leaves on Spanish Dagger bend down, while those on Spanish Bayonet do not.  High salt tolerance also makes Spanish Dagger ideal in beachfront areas. The cultivar ‘Nobilis’ is an improved cultivar with dark green leaves.

 

Adam’s Needle (Y. filamentosa) is a slow growing native plant found scattered  through the  southeastern woods. Leaves look like they have been shaved because of many curved, filamentous threads of leaf tissue found on the leaf edges. The leaf ends in a sharp spine. Plants stay small, growing no more than about 3-feet-tall. It tolerates partial shade well, provided enough air circulates to keep the plant on the dry side. There is a white striped cultivars called ‘Variegata’ with light yellow bands along the leaf edges; ‘Bright Edge’ and ‘Color Guard’ both  have brightly marked leaves with white to cream colored stripes.

 

Spineless Yucca (Y. elephantipes) is the tallest of the Yuccas, and can max out at 30 foot heights with a 15-foot spread.  Its single, thick, rough trunk is topped with strap like, four-foot-long leaves. Spineless Yucca grows fairly rapidly but usually stays under 20 feet in height, and is ideal for use in succulent gardens or large planters. The trunk can grow to be four feet thick. Sprouts often grow from the base of the trunk forming a multi-trunked tree.  Unlike Spanish Bayonet, Spineless Yucca can be used in close range of people since it lacks the sharp leaf tip.  

 

Spineless Yucca grows easily in full sun or partial shade on any well-drained soil.  Do not plant any Yucca unless soil drainage is superior. This yucca can also be grown as a houseplant if it is given plenty of sunlight.  Many Florida nurseries produce this plant for indoor foliage use.  A Spineless Yucca cultivar with striped foliage, ‘Variegata’, may be found in some nurseries, and may be gaining in popularity.

 

New Yucca plants can be grown from seed, but some cultivated yuccas must be hand pollinated where specific yucca moths are absent.  Most often, cuttings of any size are rooted to grow new plants.  Suckers at the base of the plant root quite easily.   Pest problems include scale insects, Yucca moth borers, where larvae bore through the buds and a black weevil which bores into roots and stems.  Few diseases are of major concern, except root rot if the soil is kept too moist. Leaf spots can be a problem in areas with poor air circulation, but do no real harm to the plant.

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Trade names, where used, are given for the purpose of providing specific information. They do not constitute an endorsement or guarantee of products named, nor does it imply criticism of products not named. The Florida Cooperative Extension Service - Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information, and other services to individuals and institutions that function without regard to race, color, sex, age, handicap, or national origin.  Florida Cooperative Extension Service / IFAS / University of Florida.  Larry A.  Arrington, Dean Last update: 08/15/2005 .  This page is maintained by Dan Culbert 

references

 

Gilman Edward F. and Watson, Dennis G. Spineless Yucca Yucca elephantipes {Fact Sheet ST-675]. Gainesville: Florida Cooperative Extension Service, October 1994. http://hort.ifas.ufl.edu/trees/YUCELEA.pdf

Gilman Edward F. Spanish Bayonet Yucca aloifolia [Fact Sheet FPS-614]. Gainesville: Florida Cooperative Extension Service, October , 1999. http://hort.ifas.ufl.edu/shrubs/YUCALOA.PDF 

Gilman Edward F.  Mound-Lily Yucca Yucca gloriosa Spanish [Bayonet Fact Sheet FPS-616]. Gainesville: Florida Cooperative Extension Service, October,1999. http://hort.ifas.ufl.edu/shrubs/YUCGLOA.PDF 

Gilman Edward F.  Adam’s Needle Yucca filamentosa  Spanish [Bayonet Fact Sheet FPS-615]. Gainesville: Florida Cooperative Extension Service, October,1999. http://hort.ifas.ufl.edu/shrubs/YUCFILA.PDF

 Hochstätter, Fritz. Yucca species.  Mannheim, Germany.  January 2003. http://www.yuccaagavaceae.com/introduction.html. Contains a comprehensive listing of Yucca species, including photos, based on book by compiled by this author. 

Jensen, Benny Møller.  Benny's Yucca Page. Hjørring, Denmark: 2005.  http://www.bennyskaktus.dk/Yucca_UK.htm  This site is a comprehensive webpage hosted by a serious amateur Yucca grower.

Poole, R.T., Chase, A.R. and Osborne,  L.S.  Yucca Production Guide [CFREC-A Foliage Plant Research Note RH-91-36].  Apopka: UF/IFAS Central Florida Research and Education Center, 1991.   http://mrec.ifas.ufl.edu/Foliage/folnotes/yucca.htm.

Schoellhorn, Rick and Frank, Marc.   Warm Climate Production Guidelines for Cacti and Succulents [ENHFL04-006] Gainesville: Florida Cooperative Extension Service,  2004.  http://hort.ifas.ufl.edu/floriculture/Crops/ENHFL04-006%20Cacti%20and%20Succulents.pdf.