‘Luisa’ Turnera Holds Great Potential

'Luisa' Turnera Holds Great Potential

Turnera diffusa is a widespread and variable species found throughout the tropical Americas. Commonly known as “damiana,” Turnera diffusa has figured extensively in folk medicine and is particularly noted for its aphrodisiacal properties for which there is scientific support.

In 2005, we conducted a plant exploration in Puerto Rico for species with ornamental potential. In the coastal mogotes (limestone hills) of southern Peñuelas Municipality, we encountered a population of T. diffusa. The population was striking for its small, densely hairy gray-green leaves that we perceived as more attractive than typical of the species elsewhere across its broad range. One individual in the population appeared particularly compact.

Cuttings of this individual were collected and placed at a mist propagation facility at the USDA-ARS Tropical Agricultural Research Station (TARS) in Mayaguez. Once rooted, these were shipped to the National Germplasm Repository at the Subtropical Horticulture Research Station (SHRS) in Miami, where we have propagated and evaluated the plant for the past five years. It has proven to be a dependable, problem-free ornamental with great potential as a perennial in warm climates or for annual use in the temperate zone. We have given this cultivar the name ‘Luisa’ in honor of the author Tomás Ayala-Silva’s late mother, who was an enthusiastic admirer of Puerto Rico’s native flora.

Rooting ‘Luisa’

‘Luisa’ is a multi-stemmed, densely branched evergreen sub-shrub growing to about 2.5 feet tall. The small evergreen leaves are grayish green and aromatic when crushed. The small (1/2-inch) yellow flowers are borne singly in the axils of the more terminal leaves, and though lasting only a single day, are quickly replaced by new flowers the next day.

‘Luisa’ is readily propagated from softwood cuttings throughout the year. We have found that cuttings from actively growing plants treated with a five-second basal end dip in 1,000 ppm indolebutyric acid in 50 percent EtOH root within four to six weeks when placed under intermittent mist.

We have successfully grown the cultivar in five-parts-aged pine bark: four coconut coir dust, one coarse sand (by volume). Rooted cuttings in cell packs are placed directly into 6-inch containers. The plants grow rapidly and will be saleable in 6-inch containers in six to eight months after rooted cuttings are potted. In smaller containers (4 inch), they are ready in four to six months. Trial blocks were situated in the ground at the USDA-ARS National Germplasm Repository in Miami from plants established in 6-inch containers in October 2005, April 2007 and again in March 2009 in crushed limestone and sand-fill soil similar to urban residential lots in much of South Florida. Soil was amended with three inches of 10-year-old aged compost from vegetative solid waste, incorporated into the top six inches of the site substrate.

In The Landscape

In the landscape, ‘Luisa’ should be situated in full sun and on well-drained soils. It is tolerant of alkalinity to a pH of at least 8.5 and grows equally well in slightly acidic substrates (pH 6.5). After establishment, the plant is drought tolerant, requiring supplementary irrigation only during prolonged periods of no precipitation.

Nutritional requirements appear low. We have fertilized field plantings only once annually with no apparent nutritional deficiencies observed. Once each year the plants can be cut back to half their height. No pest or disease problems have been observed in five years of cultivation history in Miami. Fruit set has never occurred at our location, so the threat of weediness appears minimal in contrast to T. subulata and T. ulmifolia, which have naturalized in many subtropical and tropical areas. The rapid rate of growth, ease of propagation and long flowering season suggest ‘Luisa’ could be marketed as an annual beyond its expected hardiness range, which we estimate to be USDA 9B-11 (USDA, 1990). Flowering occurs for most of the year in South Florida, ceasing production only in the coldest months of winter.

‘Luisa’ can be used as an edging, groundcover, bedding plant or as a container plant. Although the flowers are small, they are produced in great profusion and contrast well with the gray-green foliage, creating a conspicuous presentation in the landscape. The dwarf growth habit and small leaves and flowers are markedly different from the coarse, rangy habit of the large-flowered T. ulmifolia and T. subulata.

Small quantities of ‘Luisa’ are available for research and further evaluation purposes by request through the USDA-ARS National Plant Germplasm System as accession PI 659752.

Leave a Reply

2 comments on “‘Luisa’ Turnera Holds Great Potential

More From Varieties...
Dipladenia Sundenia

January 11, 2017

New Tropical and Foliage Plants That Offer Hidden Benefits

Tropical and foliage plants can offer extra paybacks to your customers in terms of health-promoting benefits such as filtering the air, reducing stress, and absorbing noise. Consider these new varieties, hitting the retail market in 2017, for your product mix.

Read More
craspedia-golf-beauty-danziger-feature

January 9, 2017

Growing Tips for Craspedia ‘Golf Beauty’

Laura Robles of Mast Young Plants offers advice on ‘Golf Beauty,’ a novelty plant with can’t-miss yellow flower heads and silver foliage that blooms throughout the summer.

Read More
Bride with wedding orchids.

January 7, 2017

How to Stand Out in the Orchid Market

With the popularity of the Phalaenopsis orchid growing and its saturation in the market, orchid growers are hunting for new ways to stand out from their competitors.

Read More
Latest Stories
Dipladenia Sundenia

January 11, 2017

New Tropical and Foliage Plants That Offer Hidden Benef…

Tropical and foliage plants can offer extra paybacks to your customers in terms of health-promoting benefits such as filtering the air, reducing stress, and absorbing noise. Consider these new varieties, hitting the retail market in 2017, for your product mix.

Read More
craspedia-golf-beauty-danziger-feature

January 9, 2017

Growing Tips for Craspedia ‘Golf Beauty’

Laura Robles of Mast Young Plants offers advice on ‘Golf Beauty,’ a novelty plant with can’t-miss yellow flower heads and silver foliage that blooms throughout the summer.

Read More
Bride with wedding orchids.

January 7, 2017

How to Stand Out in the Orchid Market

With the popularity of the Phalaenopsis orchid growing and its saturation in the market, orchid growers are hunting for new ways to stand out from their competitors.

Read More
California Coast

January 3, 2017

Expect Big Changes for California Spring Trials 2017

California Spring Trials 2017 will be here before you know it. Find out what you can look forward to and get a head start on planning and registering for your trip.

Read More
westerlay-orchids-feature

January 1, 2017

How Westerlay Orchids Solved Its Bacteria Problem

Water-borne bacteria was causing havoc with Westerlay Orchids’ production, so the company took preventative action to ensure the health of its plants.

Read More
nepeta-purple-wave-with-roses

December 30, 2016

Allan Armitage: Plants That Can Bring Success in the Ne…

Are you wondering which plants to grow? Here are some perennials, annuals, and herbs that are gaining popularity.

Read More
Honeybelle combo

December 27, 2016

19 New Combos for Containers Big and Small

Check out 19 combos and mixes new for the retail marketplace in 2017 that offer something for every container type.

Read More
sun-parasol-original-crimson-web

December 20, 2016

Suntory Launches Unrooted Cuttings Program for Sun Para…

While the domestically produced rooting program for the Sun Parasol will continue, growers who would like to purchase unrooted cuttings will have the opportunity for the Sun Parasol Original varieties and Garden Crimson.

Read More
santos flare

December 20, 2016

Ball Horticultural Expands Potted Plant Offerings With …

Ex-Plant, which specializes in potted plants, will become a part of Ball’s PanAmerican Seed division.

Read More

December 16, 2016

Please Take Greenhouse Grower’s 2016 Poinsettia S…

Are plant sales up or down compared to last year? How did Black Friday set the tone for this season? What varieties and sizes were your best sellers? Did you try anything new this year to appeal to younger consumer demographics? We tackle all of these questions and more to help you understand the trends in Greenhouse Grower's 2016 Poinsettia Survey.

Read More

December 13, 2016

Dümmen Orange Shares Trends And Season-Extending Tips A…

As a purveyor of a wide collection of poinsettia and potted plant genetics, Dümmen Orange offered attendees a look at current trends – and a glimpse into the future – at its annual event in Columbus, OH.

Read More
Lollipop Flaming Hot Melon combo

December 13, 2016

21 New Combos For Spring To Fall Color In 2017

With the flood of new varieties and flower colors coming on the market, there is no end to the combinations and mixes available for hanging baskets and containers.

Read More
all-america-selections-new-website-home-page

December 3, 2016

New Mobile Responsive Website From All-America Selectio…

All-America Selections has launched a newly redesigned and revamped mobile-responsive website that includes a more attractive design, enhanced search tools, and easier and simpler navigation.

Read More
Sea Breeze Catharanthus combo

December 2, 2016

Four Mixed Container Trends To Watch

Mixed containers are still one of the best-selling SKUs at retail. Pay attention to these four trends that are making their mark on multi-liner mixes and combination containers.

Read More
kelly-norris

December 2, 2016

Kelly Norris: How The “Me Too” Philosophy Affects Plant…

When you’re selling the exact same thing as everyone else, it’s unrealistic to expect customers to buy only from you.

Read More

November 29, 2016

How Changes In Plant Patent Law Could Affect Your Varie…

There is an ongoing discussion happening among plant genetics companies about the current laws and ethics of plant breeding, and what the future holds for the improved lawful protection of genetics.

Read More
endless-summer

November 29, 2016

Endless Summer Hydrangeas Will Soon Feature New Identit…

Bailey Nurseries, which first introduced the reblooming hydrangea a decade ago, says the new identity will feature a more contemporary look to appeal to current and future gardeners.

Read More
prince-tut-cyperus-grass-feature

November 28, 2016

Growing Tips For ‘Prince Tut’ Cyperus Grass

'Prince Tut’ from Proven Winners’ Graceful Grasses collection is versatile, working well in all container sizes with its columnar habit and dense canopy and filling out well in the landscape.

Read More