Tea saponin
A triterpenoid saponin from Camellia oleifera seed cake, used against slugs, snails and soil-surface pests. Effective, and genuinely hazardous to fish.
What is tea saponin?
Tea saponin is a mixture of triterpenoid saponins obtained from the seed cake left after pressing oil from Camellia oleifera. It is a by-product of tea-oil production, which makes it an unusually circular input. Note it is distinct from quillaja saponins from soapbark, which are used elsewhere in the industry, and from the tea plant Camellia sinensis.
How does tea saponin work?
Saponins are amphiphilic: a hydrophobic triterpene aglycone with hydrophilic sugar chains. That structure makes them natural surfactants, and it also lets them complex with sterols in cell membranes, disrupting membrane integrity.
Against molluscs the effect is direct and visible — saponins destroy the protective mucus layer and cause severe dehydration, which is why slugs and snails respond quickly to contact. Against soil-surface arthropods the mechanism is similar membrane and cuticle disruption, aided by the surfactant action improving wetting and coverage.
What does tea saponin not do?
It is a contact material with no residual activity once dried and degraded, so reinfestation from untreated ground is the normal failure mode. It is not selective and will affect non-target soft-bodied soil organisms in the treated zone. And it does not control molluscs by bait attraction the way iron phosphate products do, so placement relative to where the pests actually are matters more.
Is tea saponin safe?
Saponins are potently toxic to fish. Their haemolytic action on gill membranes is so reliable that plant saponins have been used historically as fish poisons for harvesting. Any application near ponds, ditches, streams or drainage that reaches surface water must be avoided, and this deserves prominence rather than a footnote.
For mammals, oral toxicity is low and saponins are poorly absorbed from the gut, but they are irritant to mucous membranes, so applicator protection applies.
Which products are built on tea saponin?
Slug Control (tea saponin from Camellia oleifera), targeting slugs, snails, mole crickets and ants, including Deroceras, Limax and Acusta species.