Recovering After Hurricane Helene: Strategies for Blueberry Growers

Horticulture Department, University of Georgia, 2360 Rainwater Road, Tifton, GA 3793-5766

On September 27, 2024, Hurricane Helene crossed South Georgia after making landfall in Florida as a Category 4 storm, producing wind gusts near 88 mph and causing severe damage to blueberry farms across the region. Numerous blueberry fields were damaged, with bushes uprooted or leaning toward the ground, and many branches broken. Farms were also left withoutelectricity for several days (Fig. 1).

Damage to plant structural organs, such as roots or crowns, can reduce water and nutrient uptake, leading to poor growth and yield reduction. Canopy damage negatively affects flower bud formation, especially when it occurs before bud initiation, potentially reducing yield the following season. Despite the threats and damage natural disasters can impose on blueberry fields, there are very few science-based recommendations available to guide growers in protecting their crops from natural disasters, such as hurricanes.

Recovery Options After Hurricane Damage

Following Hurricane Helene, many growers attempted to recover damaged plants by lifting and supporting leaning bushes using wood or PVC stakes and adding soil around the base of the bushes. Growers also pruned damaged plants to stimulate regrowth and applied humic acid and plant growth regulators to enhance the recovery process.

How the Study Was Conducted

This study was designed to evaluate whether the practices stated above (staking, adding soil, pruning, and using biostimulants) enhance plant recovery post-hurricane damage. The main objective was to test whether adding humic acid and plant growth regulators could enhance recovery.

The trial was established in two commercial farms in Bacon County, Georgia, evaluating five fields representing different cultivars (‘Farthing’, ‘Legacy’, and ‘Optimus’).and production age, based on establishment.

Three approaches (treatments) were tested:

1.  Control: undamaged plants requiring no intervention.
2. Mechanical support (Fig. 2): staking plants to stabilize leaning plants.
3. Mechanical support combined with the use of humic acids and plant growth regulators(Fig. 3): humic acids are often advertised as agents to improve soil structure, nutrient availability, and root development. Plant growth regulators such as IBA and cytokinin can stimulate root and shoot growth. Together, these products could rebuild damaged root systems and restore canopy growth.

Plant recovery was monitored by measuring:

• Canopy structure: Evaluated using leaf area index (LAI), light interception, and drone vegetation indices (NDVI and NDRE).
• Nutrient concentration: Determined through soil and leaf samples analysis. 
• Yield per plant and fruit quality.

Treatment Effects on Plant Recovery

Soil and leaf nutrient levels changed mainly with the season rather than treatment (data not shown). Across fields, humic acid and plant growth regulator applications did not result onconsistent improvements in soil fertility or leaf nutrient concentrations during the first year of data collection. 

Drone imagery, LAI assessments, and light interception measurements indicated that plant age was the primary factor influencing recovery:

• Younger fields showed minimal long-term structural damage and recovered quickly (Fig. 5 and 6).
• Older fields exhibited a reduction in canopy area (Table 1) and overall light interception(Fig. 5).
• Staking the plants or staking and incorporating humic acid and plant growth regulators did not fully restore canopy structure (Fig. 6).

Vegetation indices such as NDVI (Normalized Difference Vegetation Index) and NDRE (Normalized Difference Red Edge) reflected differences in canopy density but not among the two tested strategies (Table 1). Thus, the addition of humic acid and plant growth regulators did not enhance the recovery compared to the staking treatment alone.

Yield reductions were evident in older fields, following the same pattern observed on canopy damage (data not shown). In contrast, fruit quality traits such as berry size, soluble solids, acidity, firmness, and anthocyanins were generally unaffected by treatments or damage level(data not shown).

Management Implications

Overall, older fields were more vulnerable and slower to recover, while younger plantings were more resilient and showed faster recovery regardless of treatment.

Our results suggest:

• Staking may help stabilize plants, but it does not guarantee long-term recovery.
• Humic acids and growth regulators did not provide clear short-term benefits.
• Yield losses are more likely to occur in older fields than in younger plantings.
• Fruit quality may be maintained even when yield declines.

Recovering from hurricane damage might take several years, and we will continue to monitor these fields to identify any treatment effect over time.

Table 1. Canopy area (m2) and vegetation indices (NRDE and NDVI) were measured six months after treatment application across different blueberry fields. T0 represents the control plants that did not experience hurricane damage, T1 includes plants that were staked after the storm, and T2 includes staked plants that also received a humic acid/plant growth regulator (RADIATE®) treatment. Different letters indicate which treatments produced significantly different results (p <0.05), helping illustrate which practices enhance canopy recovery.

Funding Source:

This work was supported by the USDA National Institute of Food and Agriculture Award #: 2025-68016-4439978, AFRI Rapid Response to Weather Events.