Dormant oil is a horticultural treatment used mainly in the spring to control several harmful insects , including scale insects , spider mites, aphids and leaf miners . It works by destroying their eggs and larvae before they emerge. Applied to fruit trees, shrubs and ornamental plants that are still dormant, it effectively prevents infestations.

What is sulfur porridge?

Sulfur slurry is a natural fungicide used in organic gardening to prevent and treat fungal diseases such as powdery mildew, scab, rust and peach leaf curl . In addition to being effective against fungi, it also has an action on certain mites and insects .

Why combine dormant oil and sulfur porridge?

Combining these two treatments provides complete protection for your trees, shrubs and perennials . By combining the insecticidal action of dormant oil and the fungicidal effect of sulfur mixture , you significantly limit the risks of diseases and infestations.

Be careful though: these products do not remain in solution for very long, especially the sulfur mixture . It is essential to shake the sprayer regularly during application.

When and how to apply these treatments?

Application period

The dormant oil and sulfur mixture is applied in late winter or early spring , before the buds open. Here are the optimal conditions:

• Temperature between 12 and 15°C for at least 3 consecutive days.
• No risk of frost or precipitation .
• Apply in calm weather to avoid product drift.

Material and method of application

Use a fine nozzle sprayer for best coverage. Thoroughly spray all branches, bark and sensitive areas . Be sure to reach areas where insects overwinter.

Precautions and exceptions

Not all plants tolerate these treatments. Here are the ones to avoid:

• Blue conifers (e.g. spruce, blue juniper): horticultural oil alters their color.
• Evergreen plants (eg rhododendrons, azaleas, hollies, yews): sensitive to oils.

If you have already observed infestations of thuja leaf miner, red spiders, scale insects or apple tree diseases , prevention is essential. Anticipate the application period and obtain the necessary equipment from a garden center .

An ecological solution for a healthy garden

Horticultural oils and sulfur slurry fit perfectly into a biological control strategy. Biodegradable and environmentally friendly, they allow you to protect your crops without the use of aggressive chemicals.

By applying these treatments at the right time, you reduce the number of interventions required during the summer season and ensure optimal growth for your fruit and ornamental plants .