Dr. Rhuanito "Johnny" Soranz Ferrarezi

Assistant Professor of Citrus Horticulture

Dr. Rhuanito “Johnny” Ferrarezi leads IRREC’s citrus horticulture research and extension in the world’s premier grapefruit production region: the Indian River Citrus District. Dr. Ferrarezi has more than 17 years of experience to his position, as part of IRREC’s team to assist growers as they manage citrus greening, or Huanglongbing (HLB), the industry’s most formidable pathogen. 

Johnny is an Assistant Professor of Citrus Horticulture, focusing on precision irrigation and automation using soil moisture sensors and low-cost open-source microcontrollers, plant nutrition, variety trials, and cultural practices.

Dr. Ferrarezi works with local producers to improve irrigation management in the IRREC’s citrus experiment groves by testing different irrigation management methods and using novel irrigation systems, and at the IRREC's greenhouses by accelerating the production of citrus nursery liners using automated ebb-and-flow subirrigation. He pioneers this field, particularly due to his innovative system automated using soil moisture sensors, as can be highlighted by several refereed publications in the field.

Johnny’s water systems automation and plant nutrition expertise will help growers produce healthful fruit that will survive HLB and stay profitable. His research with low-cost automation in citrus research groves is sought-after by growers and his peers. Dr. Ferrarezi identified an irrigation smart-device that costs growers a fraction of the standard equipment being used in most groves, and is more efficient in dispensing water to commercial crops. 

His work was recognized with The Alex Laurie Award, presented to “authors of the most significant applied floriculture research paper published in any of the three refereed American Society for Horticultural Science publications during a calendar year.” He was also honored with a CIGR Award and Armand Blanc Prize.  

Another field of research is the study of plant density, soil and foliar nutrient application in grapefruit together with fertilization method/rate optimization and nutritional enhancement practices in HLB-infected groves.

The Ferrarezi Lab program includes large-scale, replicated variety trials testing new grapefruit scions and UFR and other rootstocks on grapefruit, navel orange, and mandarin in the Indian River.

Dr. Ferrarezi is a co-author on the new released Florida Citrus Rootstock Selection Guide 4th Edition (Florida Citrus Rootstock Selection Guide). The interactive website has a new look and updated information in providing a comprehensive description of standard commercial and recently released rootstocks.  The guide is a convenient, easy-to-use reference to 21 horticultural traits of 49 rootstocks. An expert system based on artificial intelligence emulates a human expert by systematically sorting information provided by users, then determining the best possible recommendation for the given rootstock.

The innovative citrus under protective screen (CUPS) system aims to exclude psyllids from young grapefruit plantings and is also a focus of Dr. Ferrarezi's research and extension program.

Dr. Ferrarezi is an active participant in the W4128 Multi-State Group “Microirrigation: A sustainable technology for crop intensification and improved water productivity”, receiving the 2017 National Water and Energy Conservation Award from the Irrigation Foundation in recognition of the conservation of water and energy relating to irrigation procedures, equipment, methods and techniques from the project.

Johnny organizes the Florida Citrus Show in Fort Pierce, an outreach event that attracts approximately 1,000 growers each year

Dr. Ferrarezi is an active participant of the UF Land Use and Facilities Planning Committee, an advisor at the Gators Citrus Club, and a member at the Horticultural Sciences Department Award Committee. 





Misc activities

Agricultural Worker Safety Training Day

Florida Citrus Show 2021

Florida Citrus Show 2020

Florida Citrus Show 2019

Programs and Projects @ UF/IFAS

Photography Contest



Rhuanito "Johnny" Ferrarezi, Assistant Professor of Citrus Horticulture