HML Silco is a high analysis potassium silicate product. Our work with this material in conjunction with our soap based products began in 2015 and the research continues today. The use of silicates, or in our case with soaps, presents huge possibilities for agricultural science.
Most research on the role of silicates within plants is fairly modern. A number of links to recent publications are provided below.
The main thrust regarding improving silicate uptake/use in plants is that it makes the plant more resilient to stresses arising out of its growing environment such as heat, water, salinity or heavy metal soils contamination. There is also evidence that silicate uptake results in plants growing more erect, with higher levels of chlorophyll, producing internally thicker cell walls which present a greater challenge to plant pathogens and pests.
Silicate uptake has historically been achieved through the soil applications, in our case it appears that soaps (fatty acids of potassium salts) also facilitate uptake through foliar applications, most efficiently when leaves or plant parts are growing or immature.
When mixed with our potassium soap based products of Protectorhml and HML32, it supports excellent spreading characteristics while retaining remarkable surface tension or ‘stickability’. Click here to see a video showing this effect.
The enhancement HML Silco provides to HML32 and sulphur for powdery mildew control was demonstrated in the Grape Powdery Mildew Prevention Trial 2015-16 at Dartmoor Rd, Hawke’s Bay.
This was further demonstrated in the 2016 UC Davis grape powdery mildew trials under the supervision of Professor Doug Gubler. In this trial, the combination led efficacy in Trial 1 against ‘best chemistry’ and many other ‘soft’ options including well known biologicals. See Page 21, Table 1 for results (potassium silicate was coded as Exp B).
The 2016-17 Machine Sprayed Powdery Mildew Prevention Trial at Ngatarawa Rd, Hawke’s Bay shows HML32/Sulphur/HML Silco having the same statistical efficacy as HML32/Sulphur/Copper. Both spray mixes have eradicant abilities as well as protectant abilities and this is a critical feature in a modern powdery mildew spray programme.
The 2017-18 Handsprayed Powdery Mildew Prevention Trial at Ngatarawa Rd, Hawke’s Bay confirms the improvement that HML Silco provides to HML32 and Sulphur as well as Protectorhml and sulphur.
HML Silco is available in liquid form in 200L drums and 15L packs.
It is Biogro certified. Organic growers should note that use of HML Silco is only permitted as an adjuvant with Biogro approved fungicides. It is not permitted within those standards to use it alone. It is also not permitted for ORGANIC exports to Canada.
HML Silco should be added first through a clean filter basket or directly into partly filled sprayer, not last as earlier labels indicate. This avoids any incompatibility issues with remnants of other products in the filter basket.
New Rate Instructions
When using HML Silco regularly as an adjuvant in a protectant spray, apply HML Silco at 100mL/100L.
When using HML Silco as an adjuvant in a protectant spray only a couple of times in a season, apply HML Silco at 270mL/100L
When using HML Silco as an adjuvant in an eradicant spray, such as HML32, sulphur and HML Silco, continue to use the current rate of 540mL/100L
Note: Read the HML Silco label carefully. If left on glass, HML Silco can cause minor damage. Wash tractor windows immediately if spraying in slightly windy conditions. A marine product called ‘Grunt E-mer- gel’ will remove it from glass but a more permanent cure would be a stick-on protective film like that used on car windows.
New Zealand Registration and Safety Information
- HML Silco (liquid) 3x5L label - Front [PDF/324KB]
- HML Silco (liquid) 3x5L label - Back [PDF/256KB]
- HML Silco (liquid) 200L label - Front [PDF/317KB]
- HML Silco (liquid) 200L label - Back [PDF/322KB]
- HML Silco (liquid) safety data sheet
- HML Silco BioGro certificate 2022–2023 [PDF/943KB]
Research and trials
- View the Grape Powdery Mildew Prevention Trial 2017-18, Ngatarawa Rd, (handsprayed) [PDF/824KB].
- View the Grape Powdery Mildew Prevention Trial 2016-17, Ngatarawa Rd (machine sprayed) [PDF/824KB].
- 'Final Report' - Control of Grape Powdery Mildew with Synthetic, Biological and Organic Fungicides - 2016 Field Trials. Department of Plant Pathology, University of California, Davis [PDF/1MB]
- Grape Powdery Mildew Prevention Trial, Hawke's Bay, NZ, 2015–16 [PDF/1.4MB]
- Grape Powdery Mildew Eradication Trial, Hawke's Bay, NZ, 2016 [PDF/2MB]
Other technical publications/papers to assist
- The Benefits of Soluble Silicon for plant health and growth - Professor Lawrence Datnoff - https://www.youtube.com/watch?v=MCZWZ5FsRhw
- A large collection of peer reviewed scientific papers on silicon use in agriculture - http://www.issag.org/2018-articles.html
- A collection of videos of scientific presentations made at the 2012 International Society for Silicon in Agriculture Conference - http://www.issag.org/articles.htm
- Role of Silicon on Plant-Pathogen Interactions. Front. Plant Sci. 8:701 [PDF/1.7MB]
- Silicon regulates Potential Genes involved in Major Physiological Processes in Plants to Combat Stress. Front. Plant Sci. 8:1346 [PDF/2.9MB]
- Silicon in Agriculture – From Theory to Practice - https://www.springer.com/gp/book/9789401799775
- Silicon in Agriculture - https://link.springer.com/chapter/10.1007/978-3-319-58679-3_8