In this Issue. Volume XX Number XX. Summer 2018, Issue 6

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1 Volume XX Number XX Summer 2018, Issue 6 In this Issue Title Page Datil Pepper Fall Festival...1 Citrus Greening Biological Contol..2 Florida Friendly Plants.. 3 Lawn Care Tips All American Selections....5 Summer Veggies Lima beans, pole beans, southern peas, watermelon and more thrive this time of year. For a complete list, download the North FL Gardening Calendar: edis.ifas.ufl.edu/pdffiles/ep/ For more information contact: UF/IFAS Extension St. Johns County Terra Freeman terraf@ufl.edu (904) FAX (904)

2 Citrus Greening Update: Asian Citrus Psyllid Parasite Now Available The Florida Department of Agriculture and Consumer Services is making the Asian Citrus Psyllid parasite Tamarixia radiata available for homeowners, in an attempt to slow the spread of Citrus Greening. Homeowners with citrus trees in their yards can apply online to have parasitic wasps mailed to their local extension agency for pickup that can then be released onto citrus trees. Pre-ordered wasps will be available for pick-up at St. Johns County Extension office on Thursday, July 19. Florida residents can apply online to the department for tiny parasitic wasps called Tamarixia that hunt the Asian citrus psyllid, an invasive insect that spreads the fatal disease citrus greening. The psyllid carries the infection, which plugs the plant s phloem, starves the tree and causes fruit to drop prematurely. Tamarixia feed on the pest and lay eggs on the underside of developing psyllid nymphs. The wasp larvae feed on and eventually kill them, which lowers the number of psyllids in the environment and helps to limit spread of the bacteria that cause the disease. The Tamarixia release program is one of several tools researchers and growers use to slow greening s spread, but there s no single solution to a complex problem like citrus greening. It s infected nearly 100 percent of the state s mature citrus trees, said Steve Futch, a citrus agent at the UF/IFAS Citrus Research and Education Center in Lake Alfred. Biocontrol methods usually operate as a series of waves, he said; when there are fewer pests, the parasite that hunts them starts to decline, too. The chances of eradicating the psyllid and the infection with Tamarixia are slim, he said but it should work well in smaller, urban environments, where wasps can fly between citrus trees on different properties. Excerpted from the Gainesville Sun and FDACS website The website for the application is: More information is available at: Methods-Development-Biological-Control/Biological-Control/Asian-Citrus-Psyllid-Biological- Control/Biological-Control-of-Asian-Citrus-Psyllid-in-Dooryard-Citrus-and-Ornamentals 2

3 Local Invasive Species Alert: Beach Vitex / Vitex rotundifolia Terra Freeman, Urban and Commercial Horticulture Agent, UF/IFAS Extension St. Johns County Introduction: As is often the case with invasive plants, beach vitex was intentionally introduced for horticultural use. Within only ten years of its introduction to the horticultural trade, it started showing signs of invasive potential. With its rapid growth rate, ability to reproduce both sexually and asexually, easy dispersal through water, and high drought and salt tolerance, beach vitex is a strong competitor. Its brittle stems can easily break off and float away to colonize other beaches. Identification: Beach vitex is a deciduous, woody vine that can reach 1 to 2 foot high and 12 feet wide with runners that can grow infinitely (some reports of up to 60 feet long!). The runners root as they trail across the sand, forming a dense mat. Leaves are 2 long by 1.5 wide, opposite, simple, rounded and grayish green with grayish hairs on the lower surface. The bluishpurple flowers are fragrant, 1 inch in diameter, and turn into round, purplish-black fruit when ripe. Location: Beach Vitex has been showing up on the Atlantic coast beaches since hurricane Irma when a population from Ponte Vedra Beach was washed out and seeds were spread. While it is not new to Florida, as it has been previously reported in Nassau County, in the panhandle, and in some inland counties, it is a concern for coastal habitats because of its ability to disperse seeds via water. It is disrupting native coastal ecosystems from NC southward and many local ordinances along the eastern seaboard have banned it. Beach vitex is listed as an invasive and not recommended by the IFAS Assessment: assessments/vitex-rotundifolia/ Concerns: Beach vitex chokes out native strand and dune species by reducing light levels under its canopy and forming dense mats that affect both native plant species and restrict nesting by endangered sea turtles. While it was once promoted as a dune stabilizing plant, it is much less effective than native dune grasses which have a significantly more fibrous root system. Control: Unfortunately, this plant is still sold as an ornamental. Please do not propagate or purchase this plant. If you have it in your landscape, dig or hand pull to remove and dispose of properly (double bag into trash). It is best to remove before the fruit ripens to avoid dispersing the seeds. Be careful to remove all stem and root fragments as they can easily regrow, even with herbicide treatments. 3

4 July, August, Sept Lawn Care Tips By Joe Kirby, Horticulture Program Assistant, UF/IFAS Extension St. Johns County Lawn Maintenance Basics FERTILIZE with a complete fertilizer in July and again in September or October. May apply iron in July instead of complete fertilizer to assist with lawn green-up. - Apply no more than one pound of nitrogen per 1,000 square feet. - Do not apply if rainfall is expected. Lawn damaging PESTS to look out for include chinch bugs, sod webworms, army worms & spittle bugs. FUNGAL DISEASES to look for include brown patch, dollar spot & leaf spot. Water on an as needed basis. If you are unsure if lawn is dry, use a moisture meter. Southern Chinch Bug Fire Ants These invasive, aggressive, reddish brown-black ants are 1/8-1/4 inch long. Can be monogyne (single queen) or polygene (multiple queens; usually ) Made up of castes: winged males, winged females, workers of varying sizes, immature ants called brood and the queen or queens. Will forage no more than 100 feet from nest. Effective strategies used to control fire ants include: -Broadcast bait applications -Individual mound treatments -A combination of broadcast baiting and individual mound treatments -Barrier and spot treatments For more information, visit Managing Imported Fire Ants in Urban Areas: 4

5 What s Your Favorite Flower? Shirley Barber, Master Gardener, UF/IFAS Extension St. Johns County Gardeners are often asked this question they can be such a fickle bunch. There are so many factors to be weighed. Is it that go-to, tried and true variety you put in your garden every year because it always performs? Or is it the latest pretty face to capture your heart? While touring the gardens at the St. Johns County Agriculture Center this Spring, I spotted a fluffy mound of pink that became my favorite flower at that moment. Verbena EnduraScape Pink Bicolor was declared a 2017 AllAmerican Selections (AAS) winner. A few plugs of this verbena were planted in our gardens last year. At first the plants were slow to take off; then the plants put out trailing stems that formed roots as it crept across the ground. The plants survived the winter and were moved in early spring to a hot, sunny area in another part of the gardens along with a few additional plants. Within several weeks the group had grown into a spectacular mound. Verbena EnduraScape obviously likes our hot humid weather and mild winters. Its tendency to trail and grow roots along the stems allows propagation by division, making it so easy to increase its presence in your garden. Unlike other Verbenas, this variety doesn t appear to be afflicted with powdery mildew. The plants reach 8 to 12 inches high and spread approximately 24 inches. The clusters are a soft pink that deepen to lavender purple towards the center of each flower (hence, the name Bicolor Pink). Site this plant in well-drained soil or in containers. The outstanding Verbena EnduraScape series is available in other colors; however Pink Bicolor earned its AAS pedigree and a place in my heart with its beauty and continuous floriferous display. Visit the gardens at the St. Johns County Agriculture Center where you might discover your favorite flower. An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Nick T. Place, dean for UF/IFAS Extension. Single copies of UF/IFAS Extension publications (excluding 4-H and youth publications) are available free to Florida residents from county UF/IFAS Extension offices. 5