LSU AgCenter Ornamental Horticulture E-News & Trial Garden Notes July 2016 Nursery, Landscape & Garden Center Updates

Compiled by Allen Owings, Professor (Horticulture), Hammond Research Station, LSU AgCenter Edited by Rick Bogren, Professor (Communications), LSU AgCenter Phone 985-543-4125; Email aowings@agcenter.lsu.edu; www.lsuagcenter.com/hammond

Headline News Mulching Trees – June 21 http://www.lsuagcenter.com/articles/page1466536581034 Texas A&M Webinars Upcoming (from Mengmeng Gu) Yan Chen from the LSU AgCenter in Hammond will be presenting PGR information for landscape shrubs and Mengmeng Gu from Texas A&M will give an overview of the 2016 California Spring Trials. Landscape plant growth control using PGRs Thursday, Aug. 4, 2016 11:00 AM - noon CDT. Dr. Yan Chen, LSU AgCenter Hammond Research Station Dr. Chen has many years of research using landscape PGRs. Many shrubs and groundcovers used in the southern landscape require routine pruning or shearing to keep their shape neat and compact. Pruning is a significant expenditure of time and a major labor cost for the landscape service industry. Reducing pruning needs has been the key motivator for the development and use of plant growth regulators (PGRs) in the landscape. Reserve your Webinar seat now at: https://attendee.gotowebinar.com/register/8934700032324977156. Highlights Newsletter from MSU Horticulturist Gene Blythe The aim of HighLights newsletter is to keep nursery and landscape professionals, Extension and research personnel, Master Gardeners, horticultural suppliers, and home gardeners up-to-date on news from the Trial Gardens and horticultural research at the South Mississippi Branch Experiment Station in Poplarville. To add a NEW SUBSCRIPTION, send an Email to blythe@pss.msstate.edu

Crape Myrtles and Bees (from Yan Chen) Crape myrtles provide pollen but not nectar to pollinators. As crape myrtles are in their peak bloom now, they are visited by many pollen-collecting pollinators - bees, carpenter bees, certain bumblebees and flies. Be sure not to spray insecticides directly to your plant for aphids or the newly spreading bark scale during the peak blooming period - aka the "beebox" to protect bees, this can be found on the chemical's label.

Imported Fire Ants in Nursery Settings (from Ansel Rankins at LDAF) Imported Fire Ants (Solenopsis invicta Buren, S. richteri Forel, or their hybrids) have been part of Louisiana’ landscape since the 1950’s. This invasive species has a very painful sting and has caused misery to humans and livestock since their introduction. Also, fire ants are known to cause damage to the electrical components of buildings and machines when they nest inside, which has cost property owners millions of dollars to correct the damages. Fire ants have been closely monitored by the United States Department of Agriculture (USDA) and the Louisiana Department of Agriculture and Forestry (LDAF) since their introduction into the state. Early efforts to eradicate the fire ants were not successful, so IFA quarantine is in place to slow the spread of this pest to areas of the country that do not have them. The quarantine covers all of the states in the Gulf Coast region and reaches into parts of Arkansas, North Carolina, Oklahoma, and Tennessee. There are also two small areas in New Mexico and California that fall into the quarantine. Because the state of Louisiana is in the IFA quarantine area, nurseries that ship out of Louisiana

are monitored to mitigate the spread of IFA to non-infested areas. All nurseries that ship any regulated plant material out of the IFA quarantine area must treat the plant material with an approved insecticide before shipping. Documentation must be provided on the invoice showing the nursery has treated the plant material which follows the shipment to its destination. Through funds provided by the USDA, LDAF administers the program that monitors these nurseries. The nursery can enter into a compliance agreement with LDAF stating that all material being shipped out of the IFA quarantine area will be treated with an approved insecticide. Also at this time they will be issued a fire ant stamp that they must use to stamp on the invoice which indicates the material has been treated and is good to ship. Prior to a nursery entering into a compliance agreement with LDAF, inspectors from LDAF will make sure the nursery knows how to treat the plant material with the correct insecticide depending on how the plants will be shipped (containers, ball and burlap, sod). By entering into the compliance agreement with LDAF, this ensures all plant material is treated before it is shipped and it also expedites the shipping process because LDAF inspectors are not required to be present for every shipment. For nurseries that do not ship many loads out of the quarantine area, they can set up an inspection with an LDAF inspector to inspect the treatment process before shipping takes place. The LDAF inspector will endorse the invoice with a stamp and maintain a record of the inspection in the district office. LDAF also monitors all shipments of honey bee colonies sent to California for almond pollination for fire ants. Commercial bee keepers treat holding yards with approved insecticides before the bees are brought in for shipment and also after the bees are loaded on to the trucks. This agreement between LDAF and nurseries has worked quite well with very few incidences of fire ants being sent out of the quarantine area from Louisiana. All nurseries that ship out of the quarantine area should have steps in place to minimize fire ants in their nursery. Scheduled applications of labeled products should be made at regular intervals and all areas kept clean of dirt and debris that may harbor fire ant colonies. Approved products and best management practices for controlling fire ants can be found at the LSU Ag Center website. More New Ornamental Sweet Taters’ (from Allen Owings) Ipomoea Sweet Caroline Bewitched After Midnight, Green With Envy, Sweetheart Jet Black are new, improved ornamental sweet potato varieties in the series from Proven Winners. Bewitched After Midnight is replacing Bewitched. Green With Envy (pictured) is adding the lime green foliage color to the series. Sweetheart Jet Black replaces Sweetheart Purple. New for 2017. Full to partial sun. Containers or landscape beds.

Louisiana Super Plants Announced for 2017 and 2018

New Loropetalum Series from Proven Winners

Variegated (pictured)

Dwarf Pink

Dwarf White

Bold

Mini

LSU AgCenter Landscape Horticulture Industry Field Day And SE Louisiana Nursery Association Trade Show

Thursday October 6th, Hammond Research Station (see flier)

‘Ruby Dreams’ and ‘Golden Dreams’ Coleus – University of Florida Breeding – Proven Winners (from Allen Owings)

‘Golden Dreams’ coleus in partially shaded planting in Hammond, LA.

‘Ruby Dreams’ coleus in partially shaded planting in Hammond, LA.

Dwarf Cannas (from MSU Horticulturist Gary Bachman) Cannas are valued for their large tropical foliage and showy, brilliantly colored flowers. They can be used as accents for the back of a landscape bed or in containers. Contrary to what their delicate appearance might make you think, canna lilies are extremely durable and quite impressive when massed together. The cannas I remember “back in the old days” were giants that needed to sit in the back row of any landscape bed. And for good reason: Many of them were over 5 feet tall. They would stand like sentries on guard with their colorful blooms as hats. It seemed at the time that this large size was the destiny of all cannas. However, one of the latest crazes in cannas is the development of dwarf selections for containers. These cannas have a compact growth habit and the ability to branch. Typically, these dwarf cannas are from 16 to 24 inches tall and are perfect thrillers for combination containers. At the Mississippi State University Coastal Research and Extension Center in Biloxi, we grow the dwarf cannas as massed bedding plants and enjoy their colorful flowers each summer. The smaller size of these varieties does nothing to limit the proud display of their gorgeous flowers. A couple of great examples are the Cannova and Tropical canna series. These plants usually have flowers that are about 3 to 4 inches across, which is pretty big for a dwarf. The beautiful flowers are soft and form on spikes held high above the wide, lush foliage. These varieties produce reliable color in shades from rose and red to yellow. Another good choice is South Pacific Scarlet, which was named an All-America Selections winner in 2013. This plant’s 4-inch flowers bloom all summer long and are a delicious blend of scarlet shades. South Pacific Scarlet thrives in hot and humid conditions, making it a perfect choice for our Mississippi gardens and landscapes. It is a little bigger than the tropical cannas, with the potential to reach 4 feet tall. Though it’s not required, deadheading prolongs the bloom period. Each plant has multiple flower shoots, and removing the spent and faded flowers allows the shoot below to develop and flower. For the best growth and flowering, plant dwarf canna in full sun, making sure they receive at least six hours each day. Keep soil moisture consistent. While the plants can tolerate drier conditions, flowering suffers. An interesting note about dwarf cannas is that most are seed-grown and will produce quite a bumper crop of seeds each summer. For the ambitious gardener, this seed production is an opportunity to collect and grow your own canna seedlings. Simply put three or four seeds in potting mix in a 3-inch container. Place the pot in a shady location -- the north side of the house would be great -- and keep it moist every day.

New addition to Cannova cannas for 2017 – Cannova Mango

New addition to Cannova cannas for 2017 – Cannova Orange Shades

LSU AgCenter Landscape Horticulture Industry Field Day and SELNA Annual Trade Show

LSU AgCenter Soil Testing and Plant Analysis Lab

LSU AgCenter Plant Diagnostic Clinic