The Ag Meter, host Nick Papagni, broadcasting from Reno, Nevada, welcomed one of agriculture’s most respected voices—Abe Isaak of AgroLiquid. Known throughout California and beyond for his deep field experience, Isaak joined the show to discuss citrus nutrition strategies that help growers protect fruit, improve brix levels, and position their crop for premium markets.
With citrus markets fluctuating and weather risks increasing, the conversation focused on proactive management—especially as groves enter the critical winter period.
Citrus Market Stability Compared to Other Crops
Isaak explained that while California citrus has faced its challenges, it has remained more consistent than crops like almonds and wine grapes, which have seen sharper market swings. Citrus growers, he noted, have generally weathered export market disruptions more effectively.
That consistency, however, does not eliminate risk—particularly as winter approaches and frost becomes a major concern.
Frost Season and Why Brix Levels Matter
As citrus moves into frost season, fruit becomes increasingly vulnerable to freeze damage. Isaak emphasized that growers should focus on raising brix levels as a proactive defense strategy.
Increasing potassium and micronutrient levels in citrus trees helps convert excess water in the fruit into sugars. Higher sugar content lowers the temperature at which fruit freezes, making it more resistant to cold damage. This is especially important for mandarins and other varieties that remain green and on the tree into spring.
By addressing nutrition ahead of frost events, growers can reduce potential damage rather than reacting after losses occur.
Using Potassium and Micronutrients to Improve Fruit Quality
Potassium plays a critical role in regulating plant functions during cold weather. Isaak explained that trees naturally pull in more potassium as temperatures drop. By supplementing potassium levels through targeted nutrition, growers can support that natural process.
Higher potassium levels help:
- Increase brix levels
- Improve fruit firmness
- Enhance natural color development
- Reduce freeze susceptibility
Micronutrients are equally important, supporting overall tree health and fruit development during this sensitive period.
Efficient Applications Without Extra Field Passes
One of the key advantages Isaak highlighted is the ability to apply nutrition without additional application costs. Growers can piggyback AgroLiquid products with existing fungicide or pesticide sprays, whether applied foliarly or through the soil.
“Soil applications are excellent for long-term benefits,” Isaak noted, “but anytime you’re already spraying, it makes sense to include nutrition.” Since application costs are often higher than product costs, combining treatments makes economic sense.
Is This the Right Time to Apply AgroLiquid?
According to Isaak, yes—this is an ideal time to apply AgroLiquid products, especially for growers concerned about frost, fruit size, or late-season quality.
He encouraged growers to rely on tissue and soil tests to guide decisions. For fruit harvested in December or later, there is still time to:
- Improve fruit size
- Increase brix levels
- Support heavy crop loads
Applications of phosphorus and potassium can help address sizing issues and improve overall fruit performance.
Pest Pressure and Preparing for Next Season
Beyond nutrition, citrus growers are also facing pest challenges—particularly mealybug infestations, which can be difficult to detect early. Isaak noted that strengthening trees through proper nutrition, applied either through the soil or foliarly, helps position orchards for better pest tolerance, improved spring growth, and stronger harvest outcomes.
Citrus Across California: One Crop, Many Microclimates
Isaak works with citrus growers from South Kern County to the Oregon border, with heavy concentrations in the Fresno area and along the east side of the San Joaquin Valley.
Microclimates play a major role in citrus management. Orchards near foothills may experience temperature differences of five degrees or more compared to nearby blocks. Coastal growers deal with milder conditions that can delay color development, while inland growers rely on colder nights to enhance brix and color.
These differences require site-specific nutrition and management strategies.
Early Outlook for the Citrus Season
While it is still early, Isaak shared an optimistic outlook. Based on current conditions, the season is off to a strong start, and growers are hopeful for good yields and quality as harvest progresses.
Rainfall, Cold Nights, and Natural Color Development
Recent rainfall raised concerns for some growers, but Isaak explained that rain is generally beneficial. Cooler evening temperatures help drive natural color development and improve potassium uptake.
Early-season citrus is often judged first by brix levels. Once sugar targets are met, fruit may still lack color and require gassing. Colder temperatures reduce that need by supporting natural color development—another benefit of maintaining strong potassium levels.
Soil vs. Foliar Feeding: Best Practices
Isaak recommended a combined nutrition approach:
- Soil applications for long-term tree health
- Foliar applications when already making spray passes
This strategy maximizes return on investment while supporting both immediate and long-term crop needs.
California Citrus vs. Florida and Georgia Citrus
Isaak also discussed regional differences. Florida and Georgia growers contend with:
- Higher wind damage affecting fruit appearance
- A greater focus on juice markets rather than fresh fruit
- Severe pressure from citrus greening disease
- Lighter, sandier soils
In contrast, many California citrus regions—especially near the Sierra foothills—have heavier soils and favorable microclimates that support strong tree performance.
How to Contact Abe Isaak and AgroLiquid
Growers interested in learning more can visit agroliquid.com, where Abe Isaak’s contact information is available.
His advice to growers is simple but critical: closely monitor tissue tests, potassium levels, and micronutrients. Strong brix levels help growers reach early markets—often the most profitable window—and ultimately deliver better returns.
Final Thoughts
Nick Papagni closed the interview by thanking Abe Isaak for sharing his insight and experience. From frost protection and nutrition timing to market strategy and regional challenges, the conversation delivered valuable, practical guidance for citrus growers navigating today’s evolving agricultural landscape.