Avocado Production: Nutrient Balance for Export Success (Part 2)

In Part 1 we looked at the challenges behind inconsistent yields, the value of nutrient-ratio analysis, and managing soil and sap data ahead of flowering and fruit set. Here we pick up at Phase 3: fruit development, nutrient translocation, long-term orchard stability, and the results growers report on the protocol.

As the crop enters the bulking phase, heavy fruit load drives up the tree's energy and nutrient demand. In well-balanced trees, sap Brix declines while fruit Brix rises, a sign energy is being translocated exactly where it is needed.

The approach, section by section

Phase 3: fruit development & translocation

Why calcium and manganese become the limiting pair as fruit bulks up.

DRIS tracks how efficiently nutrients and carbohydrates move from soil, through the canopy, into the fruit. As fruit bulks, calcium and manganese frequently turn out to be the limiting factors, even when everything else looks sufficient. Together they strengthen internal fruit structure, enzyme activity and post-harvest resilience, exactly what export-grade fruit needs.

Balanced calcium and manganese contribute to:

• Fewer physiological disorders such as grey pulp and internal browning
• Better firmness for handling, packing and shipping
• Improved cold tolerance and shelf life through export logistics

Managing alternate bearing

Protecting next season's reserves while still meeting this season's fruit demand.

Alternate bearing is one of the most persistent challenges in commercial avocado. A high-yield year can look successful yet deplete the carbohydrate reserves and micronutrient pools needed to initiate next season's flowers, swinging the orchard into a low year that complicates export contracts.

Continuous DRIS monitoring supports steadier annual production by safeguarding the tree's internal reserves while still meeting current fruit demand. Watching nutrient ratios, energy indicators and stress markers year-round lets growers act before next season's buds are compromised, flattening the on/off swing.

Outcomes growers report

What changes on the DRIS Crop Monitoring Protocol.

Producers using the DRIS Crop Monitoring Protocol have documented:

• Improved fruit-size distribution, with fewer undersized fruit below export grade
• Better internal and external quality, from balanced Ca–Mn ratios that cut grey pulp and lift firmness and shelf life
• More stable production cycles, with fewer on/off swings tied to nutrient stress
• Fewer preventable losses, catching compaction, antagonism or seasonal stress before they escalate into block failures

The monitoring protocol, step by step

Five stages, from pre-flowering baseline to multi-season refinement.

1. Pre-flowering assessment (±3 months before flowering): full soil analysis with combined sap and tissue sampling to set the baseline.
2. Seasonal monitoring (every 4–6 weeks): sap and tissue testing through flowering, set and development to track rapid shifts.
3. Integrated interpretation: DRIS weighs limitations, suppressions and stress markers into precise recommendations.
4. Timed corrections: nutrients applied to physiological demand, balance and availability over volume.
5. Continuous refinement: a multi-season orchard database that sharpens accuracy and input efficiency year on year.

Many farmers still rely on fertiliser norms developed decades ago. But soils, climates, varieties and rootstocks have changed. DRIS helps you determine whether nutrients are genuinely in balance, and what is actively limiting your crop right now.

Ronald Schroder, Director, DRIS