Sweet cherry cracking and firmness research

SILARA N30 / Evaluation pathway / Updated 24 September 2026

What published sweet-cherry research tells us about silicon treatments, cracking and firmness - and what still needs to be established for SILARA N30.

Published research is a basis for evaluation. The studies below tested other silicon products or forms. They do not demonstrate SILARA N30 performance, establish a cherry application rate, or guarantee the same orchard results.

Two-page summary · 192 KB · Full 2025 paper reviewed · Original research links below

01 / İmrak, 2025

Preharvest treatments, cracking index and firmness

İmrak, B. (2025). Mitigating Fruit Cracking of Sweet Cherries Through Ascophyllum nodosum, Glycine Betaine, Calcium Chloride, and Silicon Treatments. Applied Fruit Science 67, article 177. DOI: 10.1007/s10341-025-01375-x.

The trial in Adana, Turkey, used three randomized blocks with five trees per treatment per block, with harvest in May 2024. The silicon treatment was Zumsil Plus, applied at 400 mL per 100 L of water three weeks before harvest. This is the study treatment and dose; it is not a SILARA N30 recommendation.

What was measured

A laboratory cracking index: 50 defect-free fruit were immersed in distilled water at 20 ± 1°C and assessed after 2, 4 and 6 hours. The reported percentage changes concern this weighted index, rather than a measured percentage reduction in commercial crop losses.

Fruit quality findings

All tested treatments increased fruit firmness relative to the water control (Table 1). Brix decreased across the treatments (Table 3), so the results do not show improvement in every quality measure.

The 71% figure needs clarification. The abstract attributes a 71% lower cracking index to silicon, but Figure 1 attributes 71% to glycine betaine and 35.48% to silicon. The Results paragraph also lists an extra, unexplained percentage. We therefore do not present 71% as an established silicon effect or a SILARA N30 result.

Reported change in cracking index relative to control
Treatment Figure 1 Abstract
Silicon (Zumsil Plus) 35.48% lower 71.00% lower
Calcium chloride 26.00% lower 35.38% lower
Glycine betaine 71.00% lower 26.00% lower
Ascophyllum nodosum 26.12% higher 26.12% higher

These inconsistencies need author or publisher clarification before the numerical effects can be treated as settled. The study represents one site and season. The paper generally names the cultivar “Royal Tiago”, while its Methods uses “Royal Tioga”. It does not establish equivalence between Zumsil Plus and SILARA N30.

Read the 2025 article at Springer
Publisher purchase or institutional access may be required. This summary uses the complete paper; the publisher PDF is not redistributed here.

02 / Rombolà and colleagues, 2023

Canopy-applied sodium silicate

Four small field experiments conducted in 2002-2007 used branch treatments on 3-4 trees per treatment. Sodium silicate at 2.3 g/L was sprayed weekly, three times from colour onset. Three experiments with appreciable cracking reported significantly less cracked fruit; the fourth had less than 0.5% cracking and no treatment effect.

Cracked fruit in the field experiments (Table 2)
Cultivar / experiment Control Sodium silicate Relative reduction*
Van / 1 27.9% 13.3% 52.3%
Emperor Francis / 2 27.5% 15.7% 42.9%
New Star / 4 58.2% 41.3% 29.0%

*Calculated as (control - treated) / control × 100. These are relative reductions, not percentage-point changes.

Fruit weight decreased in one experiment. Silicon deposits were detected on fruit surfaces without detectable internal accumulation. The findings concern sodium silicate and do not validate a colloidal silica product.

Rombolà, A.D., Quartieri, M., Rodríguez-Declet, A., Minnocci, A., Sebastiani, L. & Sorrenti, G. (2023). Canopy-applied silicon is an effective strategy for reducing sweet cherry cracking. Horticulture, Environment, and Biotechnology 64, 371-378.

Original 8-page PDF, unchanged. © The authors 2023. CC BY 4.0.

Earlier findings and wider context

03 / Kaiser and colleagues, 2008

Soil-applied potassium silicate

Cracking reductions were inconsistent. One cultivar/rootstock combination had increased cracking in 2007, and insufficient rain limited 2008 comparisons. Some firmness and storage-quality benefits occurred, but the researchers could not recommend the treatment for cracking prevention.

Kaiser, C., Long, L., Whiting, M. & Azarenko, A. (2008). Prevention of cherry fruit cracking using soluble potassium silicate. Washington Tree Fruit Research Commission, final report CH-07-702.

Read the complete 2008 report
11 pages · Original research-commission host

04 / Balbontín and colleagues, 2013

Why orchard results vary

This review covers the physiological, molecular and genomic aspects of cracking, including silicon approaches and variable orchard findings. Cultivar, weather and fruit-surface factors matter. It is background evidence, not an independent SILARA N30 or colloidal silica trial.

Balbontín, C., Ayala, H., Bastías, R.M., Tapia, G., Ellena, M., Torres, C., Yuri, J.A., Quero-García, J., Ríos, J.C. & Silva, H. (2013). Cracking in sweet cherries: A comprehensive review from a physiological, molecular, and genomic perspective. Chilean Journal of Agricultural Research 73(1), 66-72.

Read the complete 2013 review
Original 7-page PDF, unchanged; distributed under the journal’s open-access policy. Publisher / DOI

Evaluation pathway

What a SILARA N30 cherry programme still needs

SILARA N30 is Bio Charge’s amorphous colloidal silica concentrate. Product-specific evaluation should establish crop safety, rate, timing and compatibility for the intended cultivar and local conditions. The published study doses above must not be substituted for a SILARA N30 cherry rate.

A useful evaluation would compare treated and untreated trees and record cracking, firmness, fruit quality, weather and any crop injury. Repeated local trials are needed before making commercial outcome claims.