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Kiwifruit Research

10 Proven Benefits for Kiwifruit Growers — ECO Soils Research

Independent research by ECO Soils Research enrolled 5 Bay of Plenty kiwifruit orchards over three years to assess the efficacy of AgriSea Soil and Foliar products. The results were highly significant — with improvements across fruit quality, storage life, vine health and soil biology.

5 Bay of Plenty Orchards, New Zealand2010-2013
+95%
More Firm Eating-Quality Fruit
–50%
Post-Storage Rots Reduced
–49%
Coolstorage Pitting Reduced
+150%
Earthworm Population (Soil)

10 Benefits Confirmed Across 5 Orchards Over 3 Years

This was not a single-orchard snapshot. The same treatments were replicated across five Bay of Plenty kiwifruit orchards over three full growing seasons, with results significant to between 90% and 99.99% confidence. The findings cover every stage of the kiwifruit value chain — from vine health in the orchard through to shelf life after coolstorage.

1

Improved fruit firmness during coolstorage

2

Improved post-coolstorage shelf life

3

Reduced new season canes lost to wind damage (blow-outs)

4

Encouraged more new canes adjacent to and from the main leader

5

Reduced the incidence of coolstorage pitting

6

Increased the calcium content of the fruit

7

Reduced the nitrogen/calcium ratio in the fruit

8

Increased fruit weight at harvest

9

Increased the percentage of 22 count size fruit

10

Increased the number of earthworms in the soil

Trial Design

On each of the 5 pergola-structured orchards, 4 treatment plots were randomly selected and each received 5 spray applications per season — 15 applications over the three years of the study.

Control

Water only — soil (500 ltr/ha) and foliage (2,000 ltr/ha)

Soil Only

AgriSea Soil Nutrition 10 ltr in 500 ltr water/ha

Foliar Only

AgriSea Foliar Nutrition 10 ltr in 2,000 ltr water/ha

Soil & Foliar

Both AgriSea products at rates above — combined programme

Application timings: new canes at 10–20cm, pre-blossom, mid-blossom, post-blossom, and 1 month prior to harvest.

Fruit Firmness After 6 Months Coolstorage

All fruit from each plot was harvested, graded, packed into trays, coolstored, then held for 36 hours at ambient temperature before penetrometer testing. The combined Soil & Foliar treatment delivered the greatest improvement in firmness.

Three-Year Average Fruit Firmness

Higher is better — firmness measured by penetrometer (kg)

Control
Soil Only
+15%
+15%
Foliar Only
+16%
+16%
Soil & Foliar
+30%
+30%

Post-Coolstorage Shelf Life

A sub-sample of coolstored fruit was held for a further 14 days at ambient room temperature, then inspected for rots, softs and firm (eating quality) fruit. The combined Soil & Foliar treatment produced dramatic improvements across all three measures.

Rots Reduced by up to 50%

Soil only: –20% rots. Foliar only: –37% rots. Soil & Foliar combined: –50% rots. Less wastage means more marketable fruit reaching consumers in good condition.

Soft Fruit Reduced by up to 32%

Soil only: –15% softs. Foliar only: –30% softs. Soil & Foliar: –32% softs. Firmer fruit after extended ambient storage gives growers and exporters a greater window for distribution.

Firm (Eating Quality) Fruit After 14 Days Ambient

Percentage of fruit in eating condition — higher is better

Control
Soil Only
+43%
+43%
Foliar Only
+79%
+79%
Soil & Foliar
+95%
+95%

Vine Health — Blow-outs & New Cane Growth

Vine structure directly affects the productivity of your orchard for years to come. AgriSea treatments reduced cane losses to wind and encouraged significantly more new cane growth — both critical for maintaining productive canopy structure.

Blow-outs Reduced

New season canes lost to wind damage — lower is better

Control
Soil Only
–30%
–30%
Foliar Only
–41%
–41%
Soil & Foliar
–44%
–44%

New Canes Grown per Vine

Canes adjacent to and from the main leader — higher is better

Control
Soil Only
+29%
+29%
Foliar Only
+32%
+32%
Soil & Foliar
+40%
+40%

Coolstorage Pitting & Fruit Calcium

Coolstorage pitting is a significant quality issue for kiwifruit exporters. AgriSea treatments dramatically reduced its incidence — and the mechanism is clear: calcium in the fruit was significantly increased, and the nitrogen/calcium ratio was reduced.

Coolstorage Pitting Reduced up to 49%

Soil only: –13% pitting. Foliar only: –38% pitting. Soil & Foliar combined: –49% pitting. Less pitting directly reduces downgrading and export rejections after storage.

Fruit Calcium Increased up to 11%

Calcium was the single element to show the most significant differences from the seaweed applications. Soil only and Foliar only: +9% calcium. Soil & Foliar: +11% calcium. Higher calcium in fruit is directly linked to reduced pitting and improved firmness.

Coolstorage Pitting Incidence

Mean percentage of fruit with pitting — lower is better

Control
Soil Only
–13%
–13%
Foliar Only
–38%
–38%
Soil & Foliar
–49%
–49%

Soil Health — Earthworm Population

Soil samples were extracted to 18cm depth using a golf greens hole cutter — 5 samples per plot, across all 20 treatment plots. The soil-only treatment produced a remarkable 150% increase in earthworm numbers, a result significant to p=0.01.

+150%
Earthworms — Soil Only Treatment
p = 0.01 ✓
+57%
Earthworms — Foliar Only Treatment
+84%
Earthworms — Soil & Foliar Treatment

The soil-only treatment was the only result to reach statistical significance for earthworm numbers (p=0.01). Earthworms are a key indicator of soil biological health and long-term orchard productivity.

Fruit Weight & Returns — Independently Confirmed

The fruit weight and economic benefits observed in this trial were independently confirmed in a follow-up study at a Te Puke kiwifruit orchard conducted by Bio Soil & Crop Ltd NZ and presented in the NZ Kiwifruit Journal.

Due to increased average fruit size and decreased reject rate, the added value for the grower was NZ$3,000 per hectare — consistent with the fruit weight benefits found in the ECO Soils Research trial.