UF/IFAS Okeechobee County Extension Service
458 Highway 98 North
Okeechobee, FL 34972-2578
Phone: (863) 763-6469
E- mail: email@example.com
Feature Article - for release the
week of September 10, 2006
Dan Culbert - Extension
|Quick Links: Names Description Invasiveness References|
Beware the Bolivians
An issue that has come into
national attention has been the “invasion” of our
country by aliens. It’s riled up folks all across the
border and has now begun to pop up as an issue in our
local neighborhood. But the USA is not the only
place where these invaders are becoming an issue.
It’s those darn Bolivian
Sunflowers that were talking about today – a tall
clumping bush with typical daisy flowers. This
plant is a tall thick-stemmed plant that is topped with
lots of attractive yellow flowers. Often planted
as a screening plant, they can thrive in our climate
year round, and have the potential to spread into
To be fair, this ornamental plant
is known by several common names. This plant has
also been called Mexican Sunflower, Honduras Sunflower,
Japanese Sunflower, and Shrub Sunflower. Tree
Marigold is another suitable common name, and I won’t
go into some of the many other foreign language names that I’ve
With all these confusing names,
it’s a good chance to show the “beauty” of
botanical names: Tithonia diversifolia is a name
that will work for both gardeners in Okeechobee and
botanists from Queensland. I’m told the first
part of the name came from a
legend: a Trojan named Tithonus was loved by the
dawn goddess Eos, but she tired of him and turned him
into a grasshopper. The species name tells us that
the leaves of this plant have several different shapes.
(And you just thought all that scientific name stuff was
just a bunch of Greek, right?)
As the common names suggest, this
is a native of the Central America and Mexico. It
is cultivated for its beautiful flowers and enormous
size. It’s a member of the Daisy family, and is
related to the orange-flowered Tithonia rotundiflora,
which is also known as the Mexican
Sunflower, a totally
|Leaves of this plant may have different shapes, and some will have deep lobes. (Different foliage = diversifolia.) Photo: UCLA Mildred E. Mathias Botanical Garden||
Bolivian Sunflower produces many large yellow flowers: Photo: B. Navez
Flowers of Tithonia diversifolia look like sunflowers. They are about 6 to 7 inches across. Photo: Bob Bierman, Plant Atlas of FL
year or two, one small branch can quickly grow
from 8 to15 feet tall, and spread to a 6-foot wide
clump. Its fast growth, upright habit and colorful
flowers have made it a seemingly popular choice for an
instant screening plant.
The six to seven inch bright golden
daisy of the Bolivian Sunflower is not a single flower,
but is a head made up of many small flowers. Around the
rim are eleven to thirteen rays that have the bright
“petals”. Inside the floral circle are 200 to
300 tubular florets, each one able to form a seed.
Because of their small size, the seed can easily
be spread by wind, further increasing the range of this
The flower fragrance of our alien
has been described by some as smelling like
while others say it has a honey-like
aroma. In our
area, Tithonia can bloom from late spring until the late
fall. The plant's
flowers are visited by butterflies and many bees, so
some refer to this as a plant that encourages wildlife
– an argument that I disagree with.
The deep leaves of this Tree
Marigold are large and have a fuzzy texture. The
larger leaves are deeply lobed. As the plant gets
taller it will form a rangy shrub with wide pithy,
unbranched stems that are leafless at their lower
heights. It is suggested that this plant be cut
back to one foot tall after the blooming period to help
control the height and width of the clump.
In Africa, this species has been used as a “natural” pesticide. Farmers make a tea from either burnt or fresh leaves and apply it to termite infested affected trees or directly on mounds to provide a limited period of protection from these insects. The large size of the plant has interested some farmers in Columbia as a biomass plant to add organic material to poor soil and as a feed source for some livestock.
A clump of T.diversifolia was planted along this fence line. As it grew taller, branches fell over the fence and rooted in the utility easement. Photo: Dan Culbert, UF/IFAS
A thicket of this alien sunflower established in the easement, crowding out most other vegetation. Photo: Dan Culbert, UF/IFAS
|Even aggressive Brazilian Pepper seedlings were suppressed by the thick growth of the Bolivian Sunflower. Photo: Dan Culbert, UF/IFAS|
I can attest to its rapid rate of
growth. When visiting a nursery about 10 years
ago, the grower gave me a foot-long one-inch thick stem
section that had a few roots. I potted it up, and
away it grew. When it reached a height of about 4
feet, I transplanted it along a fence in my back yard.
As it grew taller, some of the stems fell over the
fence. They rooted, formed new plants and
continued their spread into a pepper infested power line
This thicket continued to take over
until the 2004 and 2005 hurricanes knocked it all down.
It has since recovered well, and the new growth is back
as thick as it ever was. And now seedlings
have begun to spread down wind of the original site.
Applications of nonselective herbicides like glyphosate
have been used to rid areas of these volunteers as they
attempt to take over natural areas.
recommend that homeowners be careful if this
plant is introduced into your Florida Yard. Frost
free areas may see it take hold and invade places where
it can crowd out desirable native habitat. We
don’t need any more of these kinds of aliens in our
piece of paradise.
(Note: at this time, this plant
has not yet been assessed by the UF/IFAS
Invasive Plant Task Force.)
(Note: at this time, this plant has not yet been assessed by the UF/IFAS Invasive Plant Task Force.)
I’ve placed photos and more information on our Okeechobee web page, http://okeechobee.ifas.ufl.edu. If you need additional information on the identification or management of Bolivian Sunflower, please email us at firstname.lastname@example.org or call us at 863-763-6469. Local residents can stop by our office at 458 Hwy 98 North in Okeechobee, and visit our Okeechobee County Master Gardeners.
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. Millie Ferrer-Chancy, Interim Dean Last update: 04/11/2011 . This page is maintained by Dan Culbert
Chuba, D.K. and Muoghalu, J. I. Seed Germination and Reproductive Strategies of Tithonia diversifolia and T. rotundifolia. Lusaka, Zambia: University Of Zambia, June 2005. http://www.ecology.kee.hu/pdf/0301_039046.pdf#search=%22Tithonia%20diversifolia%22
Erdek, Paul. Tithonia
diversifolia. (Plant of the Month). Florida
Gardener.com, 8/1/04. http://www.floridagardener.com/pom/tithonia.htm
Everett, T.H. NYBG Illustrated Encyclopedia of Horticulture p. 3357. New York Botanical Garden, 1982.
Starnes, John A. "As good as gold Plant is jack-of-all-trades." St. Petersburg Times, November 11, 2006. http://www.sptimes.com/2006/11/11/news_pf/Homes/As_good_as_gold_Plant.shtml
Gulf Frilitary Butterfly on Bolivian Sunflower (c) Judson Rhodes
("Dawn") pursuing Tithonus,
Attic red-figure oinochoa by the Achilles Painter,
ca. 470 BC–460 BC, found in Vulci.