DiseaseDowny mildew control

Microbial biocontrol against downy mildew control

The effectiveness, measured

55 /100

Time horizon: 1 season

Why it works

Certain microbial agents reinforce downy-mildew defence within a programme, easing the pressure on copper.

What to measure for this pairing

Copper replacedDowny-mildew severity

Why this problem matters

Downy mildew (Plasmopara viticola) is the disease that pins the organic grower hardest. Without systemic synthetic fungicides, defence rests on copper and contact products, which only protect what they cover — forcing you to treat ahead of infection and renew after rain.

Management lives on a tension: protect the vineyard without exceeding the EU copper cap (28 kg/ha over 7 years). That means treating at the right moment, at the minimum effective rate, backed by risk models and rigorous logging of every application.

Problem indicators

Copper applied (kg/ha, 7-yr mean)Recorded infection periodsTreatments per seasonLeaf / cluster area lost

Certification & rules: Central to organic status and the EU copper cap — audited at certification.

How to apply the means

  1. 1Choose the agent suited to the target (e.g. Aureobasidium for botrytis).
  2. 2Apply preventively, respecting viability conditions.
  3. 3Integrate into a programme with copper, sulfur and prevention.
  4. 4Log as an authorised input in the notebook.

Frequently asked

Does biocontrol replace copper and sulfur?

Rarely in full. It is most effective as part of an integrated programme, reducing dependence but not eliminating contact means in high-pressure years.

Are the products sensitive to conditions?

Yes — being living organisms, temperature, UV radiation and tank-mix compatibility affect viability. Following the guidance is essential.

Same means, other problems

Same problem, other meansDowny mildew

Related reading →Biodynamic preparations: how and when to apply 500, 501 and the compost preps

How GrapeFlow helps

The proof organic certification demands — logged by plot and date.

Phytosanitary register with authorised inputs

Every treatment logged with product, rate and active substance, flagging what is allowed under organic rules — an audit-ready history.

Electronic field notebook

All operations — weeding, green manure, biocontrol — logged by plot and date, ready for organic certification.

Downy & powdery mildew risk models

Per-plot disease risk from local weather, to treat at the right moment and spend less copper and sulfur.