Southeastern Ornamental Horticulture Production and Integrated Pest Management

News alerts and tips from Southeastern universities.

Preemergence herbicide application – NOW!

Don’t let this spring-like weather fool you — winter is
coming.  Most container nurseries are well into winter preparations,
including getting ready to cover over-wintering structures.  It is
important to apply a preemergence herbicide before covering (else you
will grow a mighty fine crop of bittercress over the winter).  BUT —
it is very important to allow adequate time between  the herbicide
application and covering the houses.   Two to three weeks is
generally required.  If covered too soon, the herbicides may
volatilize inside the structure resulting in crop injury and worker exposure.

If you forget to use a preemergence herbicide this winter — please
send me a photo in the spring.  I’m always looking for a great shot
for my “I told ya so” file. 🙂

Joe Neal

Joseph C. Neal
Professor and Extension Specialist — Weed Science
Department of Horticultural Science
262 Kilgore Hall
Box 7609, NCSU
Raleigh, NC 27695-7609
919-515-9379 (phone)
919-515-7747 (fax)

Suggested Plant Species for Sites with a History of Phytophthora Root Crown Rot


Tom Creswell, Department of Botany and Plant Pathology, Purdue University

Kelly Ivors, Department of Plant Pathology, North Carolina State University

Mike Munster, Department of Plant Pathology, North Carolina State University 


Phytophthora is one genus within the group of “fungus-like” organisms known as oomycetes. Phytophthora species are capable of infecting a wide range of trees, shrubs, and bedding plants. Most plant-pathogenic species of Phytophthora cause root and crown rots and are able to persist for numerous years in soil. 

Chemical management of these diseases usually is impractical or not economical in landscapes. The following cultural management practices are recommended when Phytophthora root or crown rot has been diagnosed in a landscape.

• Remove severely affected plants.

• Prepare the site to ensure good drainage and organic matter content by adding pine bark to soil, raising beds, or planting on berms.

• Inspect all planting material and set only healthy plants into the landscape.

• Avoid overwatering and over-fertilization.

• Select plant species that are tolerant to Phytophthora when replacing plants lost to this pathogen.

Due to the large number of Phytophthora species and their wide host ranges, it is very difficult to make general recommendations about replacement plants for the landscape. The lists presented here were compiled based on published reports, Plant Disease and Insect Clinic records from North Carolina and neighboring states, and the expert opinion of many plant pathologists.

For full text, please visit:

Boxwood Blight: A New Disease of Boxwoods Recently Found in the Southeastern U.S.


Norm Dart1, Virginia State Plant Pathologist 

Mary Ann Hansen1 and Elizabeth Bush1, Extension Plant Pathologists 

Virginia Department of Agriculture and Consumer Services1, Virginia Tech

Boxwood blight (also called “box blight” in Europe), caused by the fungal pathogen Cylindrocladium buxicola, was reported for the first time in the U.S. at two North Carolina production nurseries in October, 2011. Boxwoods originating from an infected block of plants at one of the North Carolina nurseries were planted in two production fields in Virginia. The Virginia Department of Agriculture and Consumer Services and the North Carolina Department of Agriculture and Consumer Services are developing and implementing mitigation strategies aimed at aggressively removing the pathogen from infested fields and stopping the spread of this disease.


Read more at:



FREE Irrigation Webinars by The Water Education Alliance

The Water Education Alliance for Horticulture is working with University of Florida Cooperative Extension, OFA, FNGLA, and the German grower association Zentralverband Gartenbau and several experts at universities and companies on topics to help growers conserve, recirculate, and treat irrigation water.


Announcements in your e-magazines or grower association newsletters would be much appreciated (if you can make repeated announcements as new webinars are coming up, even better J!).


Registration is free at (click on “workshops”), and 45-minute presentations will run at noon EDT on the following Tuesdays:


Topic Presenter


Best Management Practices for water conservation Tom Yeager (University of Florida)


Biology of waterborne pathogens Gary Chastagner (Washington State University)


A Systems Approach for ManagingPhytophthora Diseases in Nurseries: the Importance of Water. Jennifer Parke (Oregon State University)


Monitoring water quality Paul Fisher (University of Florida)


Filtration and avoiding clogging of irrigation lines (Dramm Water)


Surface cleaning and sanitation Warren Copes (USDA-ARS)


Algae control and pond management Ken Wagner (Water Resources Services)


Pro and cons of water disinfection techniques: A European perspective Walter Wohanka (Geisenheim Research Center, Germany)


Designing water treatment systems Paul Fisher (University of Florida)

Top 10 Nursery Production Integrated Pest Management Practices in the Southeast

Anthony V. LeBude3

Matthew Chappell1

Jean Williams-Woodward2

Amy Fulcher4

Sarah White5

Steve Frank6

Joe Neal7

To download an Adobe pdf of this file, visit

Integrated pest management (IPM) is a sustainable approach to managing pests by combining biological, cultural, physical and chemical tools in a way that minimizes economic, health and environmental risks. One hundred and seventy-eight horticultural producers were surveyed in 2009-10 to determine the IPM practices used by growers in the southeastern U.S. Growers were asked a series of questions about monitoring or scouting for pests, prevention practices or interventions used to control pests. For each of the 230 questions asked, growers could answer whether they used the practice “Always,” “Often,” “Rarely” or “Never.”

Below are 10 notable practices that have a high potential impact on southeastern ornamental plant production and the combined percentage of growers that use them “Always” or “Often.”