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How Many Dollars Are Falling Off Your Greenhouse Bench?

Author: Paul Thomas

Losing plants to disease and insects, nutrition or neglect happens to all of us. Our goal for publishing the e-Gro series of alerts and seminars is to give you advanced awareness of issues and potential way to address them.  Still, losses happen, and in my recent greenhouse visits, I started noticing the trash cans were staring to hold plants that had to be trashed.  From January through early March, losses are traditionally very low, and unless there was a plug shipping problem, crops seem to do pretty well.  Right about now, we start seeing the first losses due to diseases and insect issues.  As the season goes on, we add losses due to missed irrigations, mishandling, and nutritional issues.  By the end of the growing seasons, we see loses due to leggy stretched or beyond market stage plants being dumped.  When I chat with growers, the usual statement is:  “well, it’s only 2% of the crop, or we kept losses to under 10% this year…” My response?  “Oh my….”


See the entire article here.

Three Factors That Can Impact The pH Of Growth Media

Author: Brian Sparks

The pH of water used in plant production is important when it comes to mixing with pesticides and dissolving micronutrients in water. However, according to Jose Chen Lopez, a horticulture specialist with Premier Tech Horticulture, the water pH has little influence on the pH of the growing medium. Other factors impact the pH of the growing medium.

See full article here.

Foliar Absorption of Nutrients Learning Module

It is so refreshing to see companies doing great things to educate growers! Harrell’s LLC has a tradition of doing this and the following product is a wonderful example of that.

Thanks to Harrell’s LLC for allowing us to re-post.

Welcome to the Foliar Absorption of Nutrients Learning Module

This learning module explains how plants absorb liquid nutrients through their foliage, and how to maximize uptake in your nutritional spray program.

Enter Here

USDA adds seven (7) Georgia counties to the Emerald Ash Borer Quarantine Area

On February 22, 2016 The USDA Animal and Plant Health Inspection Service (APHIS) added Barrow, Cherokee, Douglas, Fannin, Habersham, Murray, and White Counties in Georgia to the list of regulated areas for the Emerald Ash Borer (EAB). The Federal Quarantine specifically regulates the interstate movement of EAB-host wood and wood products from the quarantined areas in Georgia including firewood of all hardwood species, nursery stock, green lumber, waste, compost, and chips of ash species.


There are now 19 Georgia counties under the EAB Regulatory Quarantine. See The Georgia Forestry Commission or Georgia Department of Agriculture website for a map and list of the regulated Georgia counties and for information about EAB identification, damage symptoms, photographs, life cycle and quarantine regulations.


The Emerald Ash Borer (EAB) is a non-native and highly invasive insect that has killed tens of millions of ash trees in 25 states and in Canada since it was first discovered near Detroit, Michigan in 2002.  It is thought that EAB was accidently introduced into the U.S. from Southeast Asia in infested shipping containers and materials. EAB kills both vigorously growing and weakened ash trees.

2016 Center for Applied Nursery Research Grants Announced


Congratulations to the following researchers on their successful grant proposals in 2016. Research projects focus on agricultural engineering, environment and plant microclimate monitoring, entomology, plant pathology, soil science, horticulture, plant breeding and evaluation, new product evaluation, propagation, and water managemen. There are 5 funded projects for the year 2012 directed by researchers from the University of Georgia, and University of Florida.

The results of the research conducted at CANR benefit the entire industry. All results are published on the CANR website and presented at the Georgia Green Industry Trade Show in January.

The Center for Applied Nursery Research is open to all and presents a wonderful opportunity to observe new plant material and visually experience the projects in progress in addition to reading the final reports following project completion.

CANR is funded by special events and donations from industry and individuals. With continued support from the industry, the Center can continue to fund and provide a site for horticulture research in Georgia and the Southeast. For more information on how you can support CANR click_here

The 2016 Projects are:

Evaluating five improved genotypes of cotoneasters for container production in southeastern U.S.

Ryan Contreras

Over the past 15-20 years, production of cotoneasters has declined due to a variety of reasons, not the least of which has been a lack of breeding for improved varieties.  As Dirr points out, there are a number of problems with the genus including fire blight caused by Erwinia amylovora.  I have developed a number of selection that have proven resistant to fire blight in our greenhouse inoculation studies.  I have propagated these selections and grown them in limited numbers.  Industry input in Oregon on these selections has been extremely positive.  They root at high percentage (all >90%) and progress through production very fast; one selection in particular rooted and was transplanted into a #1 container in 1 month.  I believe these selections have potential to revive a “workhorse” genus and provide a crop for growers nationwide including areas where fire blight has limited their potential.  The objective of the proposed research is to grow these five selections alongside two industry cultivars and evaluate their production scheduling and resistance to disease (fire blight), insect (lace bug), and environmental stress (heat).

Longevity and efficacy of pre-emergent herbicides

Dr. Mark Czarnota

University of Georgia

There are many herbicide available to the nursery industry, but little scientific research has been performed to determine the longevity of the herbicide in soil-less media.  It is often thought that most preemergence herbicide provide approximately 30 to 40 days of control where weed seed growth is inhibited, and the additional month or two of weed control is just time that no weed infestation is present.  To determine the length of time that a herbicide provides weed free growth, replanting of weeds seed needs to occur weekly until no weed control is observed.  The objective of this study is to test the longevity of select herbicides on the control of select weeds, and determine the actual length of weed control that an individual herbicide can be expected to provide.


Automating leaching fraction measurements to improve water conservation, fertilizer efficiency, and plant growth during container nursery production

Amy Fulcher

Water is an essential input for container nursery crop production.  The threat of regulation, poor water quality, periodic drought, and competition for water make managing water resources a critical aspect of container nursery management.


Measuring leachate and calculating leaching fraction (leachate volume/total irrigation volume) is an effective way to determine irrigation volume and can be used to improve irrigation scheduling. Determining the leaching fraction of one plant during one irrigation cycle is typically done by manually capturing and measuring the irrigation water volume and the leachate coming out of the bottom of the container. Other methods include weighing the leachate and irrigation water, and aggregating leachate on a collection pad from multiple plants before measuring. However, manual methods of leachate measurement are time and labor intensive and therefore difficult to perform at a nursery on a scale suitable to capture day-to-day and plant-to-plant variation. Furthermore, these methods are only functional at a small scale; they would be difficult to adapt to a large-scale outdoor nursery environment under overhead irrigation.


Our objective is to design and develop automated leachate gauges that will function in an outdoor nursery setting with overhead irrigation and deliver accurate, real time data that can be used to schedule irrigation.  The proposed system will automatically adjust irrigation run time to maintain a leaching fraction of 10-20%.


Chemical fate of phosphorus in containerized nursery crop production

James Owen, Jake Shreckhise, and Alex Niemiera

Virgina Tech,

A complete fractionation of phosphorus (P) (i.e. total phosphorus, orthophosphate, dissolved phosphorus and insoluble phosphorus) in pore-water (i.e., solution residing in container substrate pores) of amended and non-amended soilless substrate has not yet been performed; furthermore, the determined fraction of total leachate phosphorus in the form of orthophosphate (plant available P) has been inconsistent between studies (Million et al. 2007; Ristvey et al., 2004). Fractioning pore-water phosphorus will provide insight on short-term quantity of plant available phosphorus in pore-water, as well as the immediate bioavailability of P leached from soilless substrate. We hypothesize that not all pore-water phosphorus is immediately plant available. Thus, our results would allow us to make fertilization recommendations based on plant available phosphorus rather than total phosphorus in pore-water. Additionally, determining the proportion of dissolved and insoluble phosphorus in leachate would aid in our understanding of the container nursery’s environmental impact due to phosphorus runoff. Therefore, our objectives are to determine (1) the concentration and form of phosphorus in pore-water of lime- and micronutrient-amended and non-amended pine bark when fertilized with controlled-release fertilizer containing nitrogen, phosphorus and potassium AND (2) the effect of pine bark source (i.e., supplier) on pore-water phosphorus form and concentration when fertilized with controlled-release fertilizer containing nitrogen, phosphorus and potassium. Preliminary experimentation at Virgina Tech in our laboratory has shown a dramatic effect of amendments on leached P fractions warranting a need for continued research described within this proposal.

Container Production Techniques of Syzygium buxifolium, An Alternative to Buxus

Donglin Zhang

University of Georgia,

Recently, boxwood blight, a devastating fungus disease (Cylindrocladium buxixola), has been reported in Georgia and 15 additional states and its alternatives are desperately needed. Syzygium buxifolium from central China shares similar ornamental features as boxwood, but is resistant to boxwood blight because it belongs to Myrtaceae. The objectives are 1) to evaluate Syzygium performance in container, 2) to investigate container production strategy for Syzygium, and 3) to address the production schedule of Syzygium as a potential new plant.

2016 Georgia Commercial Pesticide Applicator Handbook Released

Download entire pdfs for the current edition of commercial handbooks. Includes volumes 1 and 2, as well as a pdf that combines both volumes into one file. Also included is information on using the pdfs on mobile devices.

Includes all sections in VOLUME 1 of the 2016 Commercial Edition of the Georgia Pesticide Management Handbook in one pdf (475 pages) with bookmarks. Has recommendations for pest control on Field Corn; Cotton; Fruit & Nuts; Grain Millet; Grain Sorghum; Insecticidal Transgenic Crops (PIPs); Peanut; Soybean; Sugar Cane; Sunflower; Tobacco; and Vegetables. Cultural, biological, physical, and other types of control are recommended where appropriate. Standard front of book” material is also included.

GA Pest Management Handbook 2016 – Volume 2
Includes all sections in VOLUME 2 of the 2016 Commercial Edition of the Georgia Pesticide Management Handbook in one pdf (497 pages) with bookmarks. Has recommendations for pest control on Animals; Alfalfa; Aquatic Environments; Canola; Clover; Humans (Mosquito Control); Lespedeza; Non-Cropland; Ornamentals’ Perennial Grass; Small Grains; Stored Products; Temporary Grazing; Trees; Turfgrass; Vertebrates. Cultural, biological, physical, and other types of control are recommended where appropriate. Standard “front of book” material is also included.

GA Pest Management Handbook 2016 – COMBINED
Includes all recommendations found in Volumes 1 and 2 of the 2016 Commercial Edition of the Georgia Pesticide Management Handbook in one pdf (919 pages) with bookmarks. Standard “front of book” material is also included. This pdf is only available for agents.

Jan. 26: Updated bookmarks

+ Training (1)

Using the Pest Management PDFs on a Mobile Device
This is a 6 min (175 mb) video produced by Frank Watson, Wilkes County CEC, on how to use the bookmarks feature of the Adobe Acrobat Reader app in order to easily access pest management information.

Once you arrive at the page, you will have the option to log into Dropbox if you desire, but that is not necessary. Just “X” out that box and then click to stream the video. You can also use the download link at the top of the page to download file to your computer.

Note: PDFs are also searchable. Using the video as a reference, instead of tapping on the book icon on the bottom left to access the bookmarks, the magnifying glass icon will bring up a text box that will let you search by keyword. Then it will find the word and highlight its location in the document. You can use the arrows to scroll to other instances of the where the word is used in the document. This could be useful if you are looking for a specific chemical or disease; just be sure spelling is correct. You may also only want to search for part of the word, such as “blue” in order to capture both blueberries and blueberry.

For more information on using the Adobe Acrobat mobile app, see