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Cultivar selection involves weighing the advantages and disadvantages of a cultivar relative to the grower’s needs. Unfortunately, there are no perfect cultivars suited for every location and management system. The following discussion categorizes southern highbush cultivars into three groups: (1) new cultivars; (2) established cultivars; and (3) secondary and obsolete cultivars.

Accurate and precise measurement of radiation energy delivered to and absorbed by the patient's tissue is of great importance in radiation therapy (RT) quality assurance. Radioluminescence (RL) dosimetry has shown great potential for high spatiotemporal resolution dose measurement of RT fields. Implementation of efficient RL dosimetry in RT requires multidisciplinary effort and skills in optics, medical physics, radiation physics, electronics, and imaging science. In this review, a wide overview of fundamentals and applications of RL properties of media for RT dosimetry with emphasis on their potential use for multidimensional, small‐field, and ultra‐high dose rate RT dosimetry is provided.

This publication is intended to be a resource for Florida blueberry growers to use in scouting for disease and insect/mite pest damage; managing disease, insect/mite pests, and weeds; and application of certain plant growth regulators.

This publication provides background, statistics, and other information about the commercial blueberry industry in Florida.

Blackberry cultivation presents significant opportunities for fruit growers in subtropical regions, where nitrogen (N) is identified as a crucial macronutrient for optimal production. Given the variability in climate and soil conditions, determining the ideal N fertilizer amount can be complex. Effective blackberry cultivation requires careful attention to the principles of nutrient stewardship, including the selection of appropriate N sources, application rates, timing, and placement. Recommended N rates generally range from 25–45 kg/ha in the first year and 45–70 kg/ha in subsequent years, with adjustments based on plant type and regional conditions. The choice of fertilizer, particularly NH4+, is beneficial for blackberry plants, which thrive in acidic soils and show improved biomass and chlorophyll levels with this form of N. Research on N-cycling reveals its importance in supporting new plant growth, such as primocane development. However, improper N management, either excessive or insufficient, can negatively impact flower bud production and, consequently, fruit setting and yield. By using databases such as Google Scholar, Scopus, and Web of Science, this review synthesizes existing research on the role of N in blackberry cultivation, emphasizing the importance of precise fertilization practices tailored to regional climate and soil conditions. By highlighting variations in recommended N amounts and underscoring the principles of nutrient stewardship, this review aims to guide growers in achieving sustainable and high-quality blackberry production.

This publication discusses the types of hurricane damage that can be incurred in blueberry production operations, the impacts of these damages, preparations to make before the storm arrives, and suggestions on best management practices in the aftermath of a storm.

This publication provides historical background on southern highbush blueberries (SHB), and information on specific UF/IFAS cultivars that can be a helpful resource for SHB growers. Written by D. A. Phillips, J. G. Williamson, P. M. Lyrene, and P. R. Munoz, and published by the UF/IFAS Horticultural Sciences Department, revised September 2022.

There is a growing market in the United States and globally for fresh fruits and vegetables with reported health-enhancing properties. This includes blueberries, which are high in antioxidants and have been reported to improve heart health and contain anticancer properties. Fresh-market blueberry sales (conventional and organic) increased by 27% between 2013 and 2017, and that trend is expected to continue. In addition, there is an increasing level of consumer interest in organically grown produce (for environmental conservation, taste, and other perceived benefits), for which some consumers are willing to pay a premium over the price for a conventionally produced crop. This new 8-page publication of the UF/IFAS Horticultural Sciences Department discusses various aspects of organic blueberry production in Florida and is intended for use by those currently using or interested in pursuing organic production. Written by Douglas A. Phillips, Peter J. Dittmar, Philip F. Harmon, Oscar E. Liburd, Danielle D. Treadwell, and Jeffrey G. Williamson. https://edis.ifas.ufl.edu/hs1400

Pruning is an essential part of blueberry production and is used to help establish new plantings; promote postharvest growth of new foliage and fruiting wood; balance vegetative and reproductive growth; reduce disease and certain insect pressure; assist in harvesting efficiency; and promote new cane growth and plant longevity. This new 3-page publication of the UF/IFAS Horticultural Sciences Department is a discussion of pruning practices on southern highbush blueberry in Florida. Written by Douglas A. Phillips and Jeffrey G. Williamson. https://edis.ifas.ufl.edu/hs1359

This is an update and revision to HS976 addressing reproductive growth and development of blueberry.

Florida has been affected by eight hurricanes since 2000. This new 3-page publication discusses the types of hurricane damage that occur in blueberry production operations, the impacts of these damages, and some recommendations on best management practices in the aftermath of a storm. Written by Douglas A. Phillips, Jeffrey G. Williamson, and Philip F. Harmon and published by the UF/IFAS Horticultural Sciences Department. https://edis.ifas.ufl.edu/hs1342

The commercial blueberry industry in Florida has expanded significantly in both acreage and value in the past several years. The southern highbush blueberry (SHB, Vaccinium corymbosum L. interspecific hybrid) is the major blueberry type grown in Florida. The nitrogen (N) demand of young SHB differs from the northern highbush blueberry (NHB, V. corymbosum L.) and from mature blueberry plants. The objective of this study was to optimize fertigated N rates for the growth and yield of young SHB plants. One-year-old ‘Emerald’ and ‘Farthing’ plants were fertilized with 32N-0P-0K through drip irrigation at annual rates of 0, 42, 84, 168, and 336 kg N ha−1. Soil nitrate levels at multiple depths were measured along with leaf nutrient concentration, percent canopy ground cover, fruit yield and fruit quality. The results indicated that N rates had no significant effect on leaf nutrient concentrations. Greater N rates advanced bloom and harvest, increased percentage of ground cover (an indicator of canopy size), fruit yield and berry numbers per plant, but decreased mean berry diameter and weight. The soil nitrate results from both ‘Emerald’ and ‘Farthing’ revealed that the 336 kg N ha−1 treatment had a significantly greater risk for nitrate leaching than the lower N treatments in spring. The effect of N rates on fruit quality varied with cultivar and harvest season. The linear plateau regression of fruit yield and N rates indicated that the maximum yield reached at the annual N fertigation rate of 222 kg ha−1 for ‘Emerald’ and 206 kg ha−1 for ‘Farthing’.

This publication was developed to assist professionals working with blueberry producers to establish a benchmark for producers’ use of frost protection practices. This benchmark can assist in developing outreach strategies educating producers about frost protection strategies, and it can also help measure changes in producers’ frost protection behavior over time.

In Florida, early-ripening southern highbush blueberry cultivars allow growers to take advantage of high prices in the early market before other states can compete with higher volumes of berries sold at lower prices. That advantage comes with a vulnerability, however, because frosts can reduce gains. Florida growers rely on strategies like cold protection irrigation to reduce their risk of loss due to cold damage. This 9-page article by Tatiana Borisova, Tori Bradley, Mercy Olmstead, and Jeffrey Williamson describes a UF/IFAS study comparing precision cold protection irrigation to uniform cold protection irrigation to estimate the potential savings in diesel costs and water withdrawal volumes associated with the two practices and help protect Florida’s valuable and vulnerable blueberry harvest. Published by the Food and Resource Economics Department in October 2015.

The growth of the blueberry industry in the past three decades has been remarkably robust. However, a labor shortage for hand harvesting, increasingly higher labor costs, and low harvest efficiencies are becoming bottlenecks for sustainable development of the fresh market blueberry production. In this study, we evaluated semi-mechanical harvesting systems consisting of a harvest-aid platform with soft fruit catching surfaces that collected the fruit detached by portable, hand-held, pneumatic shakers. The softer fruit catching surfaces were not glued to the hard sub-surfaces of the harvest-aid platform, but suspended over them. Also, the ergonomic aspect of operating powered harvesting equipment was determined. The pneumatic shakers removed 3.5 to 15 times more fruit (g/min) than by hand. Soft fruit catching surfaces reduced impact force and bruise damage. Fruit firmness was higher in fruit harvested by hand compared to that by pneumatic shakers in some cultivars. The bruise area was less than 8% in fruit harvested by hand and with semi-mechanical harvesting system. The percentage of blue, packable fruit harvested by pneumatic shakers comprised as much as 90% of the total, but less than that of hand-harvested fruit. The ergonomic analysis by electromyography showed that muscle strain in the back, shoulders, and forearms was low in workers operating the light-weight, pneumatic shakers that were tethered to the platform with a tool balancer. The new harvesting method can reduce the labor requirement to about 100 hour/hectare/year and help to mitigate the rising labor cost and shortage of workers for harvesting fresh-market quality blueberries.

Foliar application of nitrogen and other nutrients essential for plant growth and development is an important practice for crop production. Most foliar nutrient N products contained the traditional N sources such as ammonium, nitrate and/or urea before urea-triazone N was available on the market. The traditional N sources have a greater salt index and leaf-burn potential than urea-triazone N. To avoid or minimize leaf burning, urea-triazone N fertilizers can be used instead of the traditional N sources. But growers have concerns about the safety of using triazone N fertilizers for commercial crop production because the fertilizers are still new to them. This 2-page fact sheet provides basic information on urea-triazone-based fertilizer for county faculty, crop consultants and advisors, growers, and students interested in commercial crop production. Written by Guodong Liu and Jeffrey Williamson, and published by the UF Department of Horticultural Sciences, October 2013. http://edis.ifas.ufl.edu/hs1233

To increase nutrient and water use efficiencies and reduce nutrient leaching and environmental concerns, fertigation is recommended for commercial blueberry production. In fact, successful fertigation can enhance sustainability and maximize profitability for commercial blueberry enterprises. One of the key factors in fertigation is the correct calculation of fertilizer injection rate and time for the acreage. This publication helps blueberry growers correctly calculate fertigation injection rates and times and provides reference tables for checking injection rates and times needed for a variety of production scenarios. This 3-page fact sheet was written by Guodong Liu, Jeffrey Williamson, Gary England, and Alicia Whidden, and published by the UF Department of Horticultural Sciences, March 2012. HS1197/HS1197: How to Calculate Fertigation Injection Rates for Commercial Blueberry Production (ufl.edu)

HS1125, a 9-page illustrated fact sheet by J. Ferguson, P. Andersen, J. Chaparro, and J. Williamson, discusses general concepts of subtropical production for commercial growers and homeowners and recommends cultivars for grower trials. Includes a table of chilling hours for several Published by the UF Department of Horticultural Sciences, January 2008.