Catches of the European grapevine moth in sex pheromone traps have risen over the past days across all monitoring zones of Crete, while harvest is running late in many vineyards of the late and mid-season zones. Bulletin No 24 of the Heraklion Regional Centre of Plant Protection (4 September 2026) sets an indicative spray window of 8 to 10 September for grapes that will stay on the vine past the first fortnight of the month. It also opens the post-harvest chapter, with the marking of esca-infected vines and the copper and sulfur applications against downy and powdery mildew.
The grapevine moth threatens grapes still hanging on the vine
Trap catches are increasing in the early, mid-season and late zones alike, and the larvae of the European grapevine moth (Lobesia botrana) feed inside the berries and open the way to rots. Treatment is recommended for grapes with a very low to zero tolerance for infestation that will be picked after the first fortnight of September, with indicative dates of 8 to 10 September.
In table-grape vineyards in areas with a history of Mediterranean fruit fly infestations, the bulletin recommends grapevine moth products that also carry approval against the fruit fly, so that a single application covers both pests. This is close to picking; pre-harvest intervals are strictly followed, and products with short residual activity are preferred.
Vines suspected of esca are marked now
Symptoms of the esca complex appear every year in many vineyards, and this is the period when infected vines stand out. Leaves turn brick-red or show the typical tiger-stripe pattern, with brown, yellow and green zones, shoots and grapes dry out gradually or suddenly, and a cut through the arm reveals brown discolouration of the wood.
The bulletin asks growers to mark the suspect vines now, while the symptoms are visible. Satisfactory control of the disease is achieved only preventively, with cultural measures during winter pruning and with wound paints or sprays applied right after pruning, mainly on large pruning cuts. The vines marked today will receive those treatments in a targeted way, when the Centre issues its detailed instructions at pruning time. Esca belongs to the wider group of grapevine pests and diseases that cause chronic losses in mature Mediterranean vineyards.
Downy and powdery mildew are treated after harvest
This growing season left intense downy mildew infections in several areas, with early defoliation that continues whenever dew or rain occurs. Early leaf loss prevents normal lignification of the canes, potentially affecting next year's production, while autumn leaf infections keep the fungus in the soil for 3 to 5 years. Powdery mildew found very favourable temperature, humidity and wind conditions this year, which led to very high infection pressure and intense symptoms that weaken the shoots and the overall health of the vine.
To protect the foliage from late autumn infections and to support the lignification and ripening of the canes, the bulletin recommends a post-harvest application:
- In vineyards with downy mildew infections, spraying is done with the first rains or during periods of heavy dew, preferably with copper-based products.
- In vineyards with severe powdery mildew infections, wettable sulfur is preferred.
- In vineyards infected by both fungi, a combined application is made.
Correct diagnosis comes before the application, because the two fungi leave different marks on the foliage and are controlled with different products.
How the products are chosen
Every application uses only products approved for grapevine and for the specific pest or disease, listed in the official database of the Greek Ministry of Rural Development and Food. The label defines the dose, the tank-mix compatibility and the pre-harvest interval, which is the decisive element of the choice at this time of year.
The dates and recommendations above come from the regional bulletin and apply as a general trend. Conditions vary from vineyard to vineyard, depending on microclimate, variety and infestation history, so final decisions rest on your own traps and on the latest local bulletin.
For severe or unclear infestations, consult an agronomist. Prefer cultural measures and low-impact solutions where possible, and use only approved products, according to the label instructions and the operator protection measures.
Sources
- Heraklion Regional Centre of Plant Protection, Quality and Phytosanitary Control, grapevine bulletin No 24, 4 September 2026, Greek Ministry of Rural Development and Food.
