By Kelly T. Morgan and Davie Kadyampakeni Most information provided in the 2020 3rd edition of Nutrition of Florida Citrus Trees is still sound for healthy citrus trees under Florida production conditions. Past information on nutrients, application methods, leaf and soil sampling, and irrigation scheduling are also effective for management of huanglongbing (HLB)-affected trees. However, research conducted since HLB was …
The Fate of Phosphorus in Florida Citrus Soils
Multi-county citrus Extension agent Chris Oswalt discussed the fate of phosphorus in Florida citrus soils in the September Extension newsletter, Citrus from the Ridge to the Valley. Excerpts from his article follow. The amount of phosphorus in soil is closely related to the potential availability of this phosphorus to plants … Potentially available soil forms of phosphorus are dependent on …
Stepping Up Phosphorus Sustainability
Two University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers have joined a national research effort to promote phosphorus sustainability across the United States. The researchers will work under the funding auspices of the National Science Foundation’s Science and Technology Center in the newly established Science and Technologies for Phosphorus Sustainability (STEPS). In addition to the University of …
Root Hair Enhancement With Low Phosphorus Concentrations
By Laura Waldo and Arnold Schumann It has been the accepted belief for many years that citrus varieties and rootstocks do not develop root hairs. However, research has shown that root hair growth can be stimulated when soil phosphorus (P) concentrations are extremely low. It is possible that in Florida, citrus roots could fail to produce root hairs due to …
Citrus Nutrient Management Recommendations Continue to Evolve
When HLB arrived in Florida, it changed the world for citrus growers, and a lot of other things had to change with it. One of the biggest changes has been how growers manage their fertilizer programs. The nutrient recommendations that had been developed by the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) before HLB became outdated because …
Insights on Soil Amendments, Soil pH and Nutrient Availability
By Davie Kadyampakeni, Tripti Vashisth and Duplicate Sambani The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) conducted an experiment for four and a half years to determine effects of soil amendments on soil pH. The impacts of fulvic acid, humic acid and sulfuric acid with and without elemental sulfur were compared. Canopy size, fruit yield, fruit quality, …
Citrus Nutrient Research Update
By Davie Kadyampakeni, Muhammad Shahid and Alisheikh Atta Current citrus nutrient guidelines are based on studies of healthy citrus trees conducted in the pre-huanglongbing (HLB) era. These guidelines may no longer be valid for the present situation where 100% of mature citrus trees in Florida are HLB-affected. Scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) …
Foliar Feed Your Trees
By Mongi Zekri Foliar fertilizer application is certainly not a new concept to the citrus industry. For over six decades, foliar fertilization has been recommended to correct zinc, manganese, boron, copper and magnesium deficiencies in citrus. It is now common knowledge in agriculture that properly nourished crops may tolerate insect pests and diseases. Traditionally, citrus growers try to achieve optimum …
The Effect of Soil pH on Nutrient Availability
By Chris Oswalt Soil pH influences nutrient availability. This article considers the specific fate of nitrogen, phosphorus and potassium in soils with elevated pH values. The discussion also assumes that these effects would be similar to conditions in the wetted zone where micro-sprinkler irrigation has raised soil pH. NITROGEN Soil pH can affect several reactions involving nitrogen in the soil …
Greening Study: Extra Fertilization Doesn’t Increase Yield
A study carried out by Brazil’s Fundecitrus in partnership with the Agronomic Institute (IAC) showed that additional fertilization of orchards had no effect on increasing the production of trees with citrus greening. The research was conducted in well-nourished adult orchards with a low incidence of greening. Results were published in January in the journal PhytoFrontiers of the American Society of …
Nutrition Remains a Critical Element as New Therapies Roll Out
Growers have largely adopted new trunk-injection therapies to fight the effects of HLB in citrus groves. In addition, plant growth regulators have helped improve tree health and fruit retention. One University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) scientist reminds growers to maintain their fertilizer programs as the new therapies are deployed. Davie Kadyampakeni, UF/IFAS associate professor of …
Breeder Advice on Nutrition, Scions and Rootstocks
Citrus breeder Jude Grosser recently shared tips on tree nutrition and discussed some scion/rootstock combinations that should work well for trees producing juice oranges. NUTRITIONGrosser became very interested in citrus nutrition several years ago in an effort to keep his newly bred trees healthy in the face of HLB. The University of Florida Institute of Food and Agricultural Sciences professor …
Integrating Use of Organic Soil Amendments and Weed Management
By Ute Albrecht, Ankit Pokhrel, Sarah Strauss and Ramdas Kanissery The soils in most Florida citrus production areas are sandy. They have less than 1% organic matter and a low cation exchange capacity (CEC). This makes them prone to nutrient leaching, especially after heavy rainfall events in the summer. HUMIC SUBSTANCESOne way to improve soils is by amending them with …
Organic Juice Company Reports Earth-Friendly Practices
In celebration of Earth Day on April 22, Uncle Matt’s Organic described how it uses numerous environmentally friendly practices. The company said use of cover crops in its groves helps control weeds and promotes healthy soil. The complex root systems from the cover crops nurture robust biodiversity in the soil. This ecosystem provides water retention, nutrient availability and carbon capture. …
Lessons Learned From HLB as an Immune-Mediated Plant Disease
By Nian Wang How the huanglongbing (HLB) pathogen Candidatus Liberibacter asiaticus (CLas) causes damage to infected citrus trees has been widely debated. A recent study demonstrates that HLB is an immune-mediated plant disease (Ma et al., 2022). It was discovered that CLas infection of citrus stimulates systemic and chronic immune response in phloem tissues, including reactive oxygen species (ROS) production, …
Oak Mulch Can Improve Florida Flatwoods Soil
By Lorenzo Rossi With no cure for HLB available, searching for alternative mitigation strategies is an urgent priority for a sustainable citrus industry. Interest has grown regarding the use of organic amendments to improve the fertility of Florida native soils. Although hardwood mulch applications have been demonstrated to improve both tree health and soil fertility in other fruit industries, little …
Cover Crop Considerations for Citrus
By Amir Rezazadeh Cover crops protect the soil from sunlight, wind and heavy rain, which enhances soil microbial populations and improves soil structure, water infiltration and root penetration. A reduction in soil crusting, erosion, runoff and nutrient leaching are additional advantages. Through improved nitrogen cycling and nutrient retention, cover crops increase soil fertility. ORGANIC MATTER SOURCECover crops offer an inexpensive …
The Most Critical Step to a Good Nutrition Program
By Tripti Vashisth, Faisal Shahzad and Jamie Burrow Leaf nutrient analysis is an important part of a successful citrus management program. Good fertilization practices are critical for optimal crop production, especially in HLB conditions. The two main objectives of nutrition management in citrus are 1) optimum and consistent yield and 2) building a strong tree that grows and produces year …
Updates for Citrus Nutrient Best Management Practices
By Kelly T. Morgan, Davie Kadyampakeni and Tripti Vashisth This article reviews current University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus fertilizer recommendations and provides updated information about recently approved recommendations for secondary macronutrients and micronutrients. Citrus growers have been very concerned about fertilizer applications and nutrient management since citrus greening (huanglongbing or HLB) was found in …
Sneak Peek: December 2022 Citrus Industry
Need the latest nutrient recommendations for growing citrus in Florida? Find updates for nutrient best management practices in the December issue of Citrus Industry magazine. The article, by Kelly Morgan, Davie Kadyampakeni and Tripti Vashisth, details recently approved recommendations for secondary macronutrients and micronutrients. The new advice is based on University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) …