Paraffin oil

Paraffin oil belongs to the class of contact insecticides and acaricides, consisting of highly refined mineral oils. The primary mode of action is physical rather than chemical: it works by covering the insect's or mite's body with a thin oil film.

This film physically blocks the respiratory pores, known as spiracles, which are used by insects for gas exchange. Deprived of oxygen, the pests die from asphyxiation shortly after the treatment.

Beyond its lethal effect on active stages, paraffin oil is highly effective against pest eggs. By coating the eggs, the oil impairs their structural integrity and prevents larvae from hatching, effectively reducing the next generation of pests.

A significant advantage of paraffin oil is that pests cannot develop resistance to it. Since the mode of action is strictly physical (suffocation), there is no biological pathway for insects to adapt, ensuring consistent efficacy over many years of use.

Additionally, these oils serve as effective adjuvants in tank mixes. The oil-based composition helps improve the adhesion of other pesticides, ensuring better penetration of active ingredients through the waxy cuticles of leaves or insect shells.

Paraffin oil is widely used to manage a variety of pests that either have hard protective shells or are difficult to reach with systemic pesticides. It is particularly effective against the following groups:

• Scale insects and soft scales
• Mites (spider mites, gall mites)
• Aphids and psyllids
• Mealybugs
• Eggs of various insect and mite species

The application is most beneficial during dormant periods or before the start of the growing season. Cleaning the tree bark from overwintering pests significantly lowers the infestation pressure during the spring growth phase.

Due to its selective nature, paraffin oil is a staple in integrated pest management (IPM) programs. It provides effective pest control while remaining relatively gentle on many beneficial insect species when used correctly.

Because the action is strictly contact-based, success depends entirely on thorough coverage. It is essential to ensure that the spray reaches all parts of the plant, including crevices in the bark and the undersides of leaves.

Application rates for paraffin oil vary depending on the plant species and the specific growth stage. During the dormant season (pre-bud burst), higher concentrations are typically used to achieve a "cleansing" or eradication effect.

During the active growing season, application rates are significantly reduced to prevent phytotoxicity to young, tender foliage. Always follow the manufacturer's specific labeling, as oil viscosity and purity can differ between products.

Optimal treatment times are early morning or late evening at temperatures between +5°C and +25°C. Avoid applying the product if freezing temperatures are expected shortly after application, as this can cause plant damage.

Paraffin oil usually has very short or non-existent pre-harvest intervals (PHI). However, users should always verify the regulations specific to their crop to ensure full compliance with safety and quality standards.

Be cautious when preparing tank mixes. Do not mix paraffin oil with sulfur or captan, as this combination is highly likely to cause severe leaf scorch and damage to the plant's vegetative organs.

Avoid application during extreme heat (above +30°C). High temperatures accelerate evaporation, which can cause the oil film to trap heat or interfere with leaf transpiration, potentially leading to leaf burning.

Do not apply during the flowering stage to protect pollinators. Furthermore, avoid using on plants that are stressed due to drought, overwatering, or root system damage, as these plants are more susceptible to phytotoxic side effects.

Always use personal protective equipment, including gloves and goggles, even though paraffin oil is generally considered to have low toxicity to mammals. Direct contact with the concentrate can still cause skin or eye irritation.

Store the product in its original, sealed container in a cool, dry place out of reach of children and pets. Prevent the oil from freezing, as freezing disrupts the emulsion stability, causing the components to separate and reducing efficacy.

Dispose of containers and leftover material according to local environmental regulations. Never allow oil runoff to enter ponds, streams, or other water bodies, as the oil film on the water surface prevents oxygenation, which is lethal to fish and aquatic life.