Impatiens are known by many names including “touch-me-not” and &#8220;busy lizzie&#8221;.  However, almost everyone knows that impatiens are common bedding annuals that bring seasonal color and easy care.  While once known to be used exclusively in partly shaded/shaded areas, newer types of impatiens tolerate more sun – some types even grow in Florida year-round taking [&#8230;]

<figure id="attachment_8725" aria-describedby="caption-attachment-8725" style="width: 293px" class="wp-caption alignright"><img fetchpriority="high" decoding="async" class=" wp-image-8725" src="https://blogs.ifas.ufl.edu/charlotteco/files/2024/03/20240221_132742-253x300.jpg" alt="a cluster of pink flowers" width="293" height="347" /><figcaption id="caption-attachment-8725" class="wp-caption-text">New and Improved Impatiens Hybrids &#8211; SunPatiens®</figcaption></figure>
Impatiens are known by many names including “touch-me-not” and &#8220;busy lizzie&#8221;.  However, almost everyone knows that impatiens are common bedding annuals that bring seasonal color and easy care.  While once known to be used exclusively in partly shaded/shaded areas, newer types of impatiens tolerate more sun – some types even grow in Florida year-round taking the heat and humidity in stride.
Our old-fashioned impatiens took a hit a few years ago when downy mildew devastated them with this blight.  Fast forward to the present and not only do we have downy mildew resistant varieties thanks to breeders, but also New Guinea impatiens known for their downy mildew resistance, and also SunPatiens® hybrids that do not get downy mildew and love full sun, hot temperatures, and humid weather.  As a group, impatiens do best from October through April as a flowering bedding or container plant.   The more traditional newer downy mildew resistant varieties will do best in part-shade to shade sites.  These bedding plants easily brighten up a shaded area with a multitude of colors in red, orange, pink, and white. New Guinea impatiens do best during this season in our area with morning sun and afternoon shade the preferred environment, although they can tolerate more sun than your traditional impatiens.  Although some cultivars have colorful foliage, they will not flower during the heat of summer.  Crucial to all impatiens is moist, but well-drained soil.  Proper moisture levels can even help some types of impatiens tolerate more sun.
Perhaps the biggest innovation in recent years has been the SunPatiens® hybrids from Japan.  SunPatiens® were developed by crossing New Guinea impatiens and wild impatiens.  As noted earlier, they flower year-round in Florida being very tolerant of heat and humidity &#8211; good news for gardeners nurturing flowering bedding plants during our brutal summers.  With these attributes comes downy mildew resistance making them bullet-proof against this disease as well.  Sufficient watering is still key to success with this type of impatiens. SunPatiens® can actually be grown as a perennial in our area and prefer full sun – in fact, avoid fully shaded sites if possible.
Every problem bring opportunities and impatiens are certainly examples.  All of the impatiens mentioned are readily available at all garden centers and nurseries.  The color, the variety and now the improvements made to impatiens make them versatile and usefully ornamental to our local landscapes.  For more information on all types of bedding plants suitable for area, or to ask a question, you can also call the Master Gardener Volunteer Helpdesk on Mondays, Wednesdays, and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Ralph E. Mitchell is the Director/Horticulture Agent for UF/IFAS Extension Charlotte County. He can be reached at 941-764-4344 or <a href="mailto:ralph.mitchell@charlottecountyfl.gov">ralph.mitchell@charlottecountyfl.gov</a>. Connect with us on social media. Like us on Facebook <a href="https://www.facebook.com/CharlotteCountyExtension">@CharlotteCountyExtension</a> and follow us on Instagram <a href="https://www.instagram.com/ifascharco/">@ifascharco</a>.
Resources: 
Gilman E. F. &amp;Howe, T.  (1999) Impatiens wallerana.  The University of Florida Extension Service, IFAS. 
Tancig,  M. (2017) Impatiens for Sun and Shade.  The University of Florida Extension Service, IFAS – Leon County 
UF/IFAS Gardening Solutions (2017) Impatiens. The University of Florida Extension Service, IFAS. 
UF/IFAS Gardening Solutions (2017) Powdery Mildew vs Downy Mildew.  The University of Florida Extension Service, IFAS. 
McCormick, K. (2020) Questions from The Plant Clinic: The Return of Impatiens.  The University of Florida Extension Service, IFAS &#8211; Seminole County. 
Schubert, T. (2012) Downy Mildew of Impatiens walleriana caused by Plasmopara obducens. FDACS. 
North Carolina Extension Plant Toolbox (2024) Impatiens x hybrida SunPatiens® N.C. Cooperative Extension. 
Missouri Botanical Garden (2024) Impatiens hawkeri. <a href="https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.missouribotanicalgarden.org%2FPlantFinder%2FPlantFinderDetails.aspx%3Fkempercode%3Db665&amp;data=05%7C02%7CPaul.Schumaker%40charlottecountyfl.gov%7Cb5147226a9984e6b4c7508dc370e213c%7C6e60678d3f1f4282a0336669a73e14ad%7C0%7C0%7C638445781106852246%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&amp;sdata=3xCHUaIVbxIUimAKNEVNpZdMAbX4XvK5jeA7Q8T%2BUTQ%3D&amp;reserved=0">https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b665</a>. 
Bachman,  G. R.  (2024) Plan garden for SunPatiens and New Guinea impatiens. Mississippi State University Extension.

New and Improved Impatiens Hybrids – SunPatiens®
Impatiens are known by many names including “touch-me-not” and “busy lizzie”.  However, almost everyone knows that impatiens are common bedding annuals that bring seasonal color and easy care.  While once known to be used exclusively in partly shaded/shaded areas, newer types of impatiens tolerate more sun – some types even grow in Florida year-round taking the heat and humidity in stride.
Our old-fashioned impatiens took a hit a few years ago when downy mildew devastated them with this blight.  Fast forward to the present and not only do we have downy mildew resistant varieties thanks to breeders, but also New Guinea impatiens known for their downy mildew resistance, and also SunPatiens® hybrids that do not get downy mildew and love full sun, hot temperatures, and humid weather.  As a group, impatiens do best from October through April as a flowering bedding or container plant.   The more traditional newer downy mildew resistant varieties will do best in part-shade to shade sites.  These bedding plants easily brighten up a shaded area with a multitude of colors in red, orange, pink, and white. New Guinea impatiens do best during this season in our area with morning sun and afternoon shade the preferred environment, although they can tolerate more sun than your traditional impatiens.  Although some cultivars have colorful foliage, they will not flower during the heat of summer.  Crucial to all impatiens is moist, but well-drained soil.  Proper moisture levels can even help some types of impatiens tolerate more sun.
Perhaps the biggest innovation in recent years has been the SunPatiens® hybrids from Japan.  SunPatiens® were developed by crossing New Guinea impatiens and wild impatiens.  As noted earlier, they flower year-round in Florida being very tolerant of heat and humidity – good news for gardeners nurturing flowering bedding plants during our brutal summers.  With these attributes comes downy mildew resistance making them bullet-proof against this disease as well.  Sufficient watering is still key to success with this type of impatiens. SunPatiens® can actually be grown as a perennial in our area and prefer full sun – in fact, avoid fully shaded sites if possible.
Every problem bring opportunities and impatiens are certainly examples.  All of the impatiens mentioned are readily available at all garden centers and nurseries.  The color, the variety and now the improvements made to impatiens make them versatile and usefully ornamental to our local landscapes.  For more information on all types of bedding plants suitable for area, or to ask a question, you can also call the Master Gardener Volunteer Helpdesk on Mondays, Wednesdays, and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Ralph E. Mitchell is the Director/Horticulture Agent for UF/IFAS Extension Charlotte County. He can be reached at 941-764-4344 or ralph.mitchell@charlottecountyfl.gov. Connect with us on social media. Like us on Facebook @CharlotteCountyExtension and follow us on Instagram @ifascharco.
Resources:
Impatiens wallerana.  The University of Florida Extension Service, IFAS.
Impatiens walleriana caused by Plasmopara obducens. FDACS.
Impatiens x hybrida SunPatiens® N.C. Cooperative Extension.
Impatiens hawkeri. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b665.
Bachman,  G. R.  (2024) Plan garden for SunPatiens and New Guinea impatiens. Mississippi State University Extension.

Impatiens are known by many names including “touch-me-not” and “busy lizzie”.  However, almost everyone knows that impatiens are common bedding annuals that bring seasonal color and easy care.  While once known to be used exclusively in partly shaded/shaded areas, newer types of impatiens tolerate more sun – some types even grow in Florida year-round taking […]

Enjoy the new and improved touch-me-not

BALM, Fla. – If you’re impatient for impatiens, a University of Florida scientist has good news for you: Some varieties of the popular flower resist the deadly downy mildew disease better than others. Many people love to plant impatiens – also known as the “Touch Me Not” &#8212; in their gardens, yards and patios because [&#8230;]

BALM, Fla. – If you’re impatient for impatiens, a University of Florida scientist has good news for you: Some varieties of the popular flower resist the deadly downy mildew disease better than others.
Many people love to plant impatiens – also known as the “Touch Me Not” &#8212; in their gardens, yards and patios because of their bright, colorful flowers and tolerance to shade, said Zhanao Deng. The UF/IFAS ornamental plant breeder leads cutting-edge research to find out how he can bolster the impatiens industry by eliminating the downy mildew pathogen.
“Downy mildew is a highly destructive disease in a wide range of crops worldwide, not just impatiens,” said Deng, a UF/IFAS environmental horticulture professor at the Gulf Coast Research and Education Center. The disease can cause extensive damage to lettuce, basil, melon, squash and grapes, among others.
Several outbreaks of impatiens downy mildew have been reported in Europe, Australia and North America. The disease has translated to decreases in wholesale values of impatiens in the United States from about $150 million in 2005 to $65 million in 2015.
But better days are ahead for nurseries, garden centers and flower-loving consumers.
Through extensive testing, Deng and his research team found two New Guinea impatiens varieties that can resist downy mildew throughout the flower’s entire life, even when their tiny plants first emerge from seeds. To allow rapid testing of impatiens varieties and breeding materials, the researchers developed a method to inoculate impatiens, and they found which varieties are more resistant or more susceptible to the pathogen when impatiens plants are at their early growth stage.
They tested 16 garden impatiens and 16 New Guinea impatiens varieties in Florida. Their findings, as just published in the <a href="https://www.nature.com/articles/s41438-021-00543-w">journal Nature Horticulture Research</a>, showed all New Guinea impatiens varieties resisted the pathogen after their first true leaves have emerged.
“However, many of these New Guinea impatiens varieties have an Achilles’ heel: They are susceptible to downy mildew at the stage when the young plants first emerged from seeds,” Deng said. “More importantly, we found two New Guinea impatiens varieties that didn’t have this vulnerability to downy mildew. They had strong resistance even when they first emerged from seeds. These varieties can be very important sources of resistance to downy mildew.”
Within the New Guinea impatiens flowers, resistance to the pathogen varied. Through genetic testing, Deng and his team found some:
<ul>
<li>Showed susceptibility to downy mildew all the time.</li>
<li>Showed resistance all the time.</li>
<li>Were susceptible at the embryonic leaf stage followed by resistance at true leaf and adult plant stages.</li>
</ul>
Scientists used DNA sequencing and bioinformatics to find genes associated with downy mildew resistance. The DNA sequencing produced large datasets. To sort through all the information and arrive at their findings, Deng and his team used the UF HiPerGator supercomputer on the main campus in Gainesville.
Findings from the new research are critical as nurseries and plant buyers eye disease-resistant impatiens flowers as the plant makes a comeback.
&#8220;Impatiens is one of the top-selling bedding flowers in the United States,” Deng said. “In 2018 alone, impatiens contributed a wholesale value of more than $109 million. And we hope to help improve those sales, helping nurseries, garden centers and consumers.”
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The mission of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS brings science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents. 
<a href="http://www.ifas.ufl.edu">ifas.ufl.edu</a> | <a href="https://twitter.com/UF_IFAS">@UF_IFAS</a>
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BALM, Fla. – If you’re impatient for impatiens, a University of Florida scientist has good news for you: Some varieties of the popular flower resist the deadly downy mildew disease better than others.
Many people love to plant impatiens – also known as the “Touch Me Not” — in their gardens, yards and patios because of their bright, colorful flowers and tolerance to shade, said Zhanao Deng. The UF/IFAS ornamental plant breeder leads cutting-edge research to find out how he can bolster the impatiens industry by eliminating the downy mildew pathogen.
“Downy mildew is a highly destructive disease in a wide range of crops worldwide, not just impatiens,” said Deng, a UF/IFAS environmental horticulture professor at the Gulf Coast Research and Education Center. The disease can cause extensive damage to lettuce, basil, melon, squash and grapes, among others.
Several outbreaks of impatiens downy mildew have been reported in Europe, Australia and North America. The disease has translated to decreases in wholesale values of impatiens in the United States from about $150 million in 2005 to $65 million in 2015.
But better days are ahead for nurseries, garden centers and flower-loving consumers.
Through extensive testing, Deng and his research team found two New Guinea impatiens varieties that can resist downy mildew throughout the flower’s entire life, even when their tiny plants first emerge from seeds. To allow rapid testing of impatiens varieties and breeding materials, the researchers developed a method to inoculate impatiens, and they found which varieties are more resistant or more susceptible to the pathogen when impatiens plants are at their early growth stage.
They tested 16 garden impatiens and 16 New Guinea impatiens varieties in Florida. Their findings, as just published in the journal Nature Horticulture Research, showed all New Guinea impatiens varieties resisted the pathogen after their first true leaves have emerged.
“However, many of these New Guinea impatiens varieties have an Achilles’ heel: They are susceptible to downy mildew at the stage when the young plants first emerged from seeds,” Deng said. “More importantly, we found two New Guinea impatiens varieties that didn’t have this vulnerability to downy mildew. They had strong resistance even when they first emerged from seeds. These varieties can be very important sources of resistance to downy mildew.”
Within the New Guinea impatiens flowers, resistance to the pathogen varied. Through genetic testing, Deng and his team found some:
Showed susceptibility to downy mildew all the time.
Showed resistance all the time.
Were susceptible at the embryonic leaf stage followed by resistance at true leaf and adult plant stages.
Scientists used DNA sequencing and bioinformatics to find genes associated with downy mildew resistance. The DNA sequencing produced large datasets. To sort through all the information and arrive at their findings, Deng and his team used the UF HiPerGator supercomputer on the main campus in Gainesville.
Findings from the new research are critical as nurseries and plant buyers eye disease-resistant impatiens flowers as the plant makes a comeback.
“Impatiens is one of the top-selling bedding flowers in the United States,” Deng said. “In 2018 alone, impatiens contributed a wholesale value of more than $109 million. And we hope to help improve those sales, helping nurseries, garden centers and consumers.”
-30-
The mission of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS brings science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents. 
ifas.ufl.edu | @UF_IFAS

BALM, Fla. – If you’re impatient for impatiens, a University of Florida scientist has good news for you: Some varieties of the popular flower resist the deadly downy mildew disease better than others. Many people love to plant impatiens – also known as the “Touch Me Not” — in their gardens, yards and patios because […]

Impatiens

Publications

Impatiens Downy Mildew

Impatiens x New Guinea Hybrids New Guinea Impatiens

Enjoy the new and improved touch-me-not

Genetic testing shows some ‘Touch-Me-Not’ flowers resist deadly disease