Red spider mites, scientifically known as tetranychid mites, notably Tetranychus urticae, are tiny arthropods of the chelicerate subphylum, in the arachnid class. These mites measure less than 0.5 millimetres and are often recognisable by their colouring, which varies from brick red to yellow-green depending on the season and their diet. They are distinguished by their short, thick bristles, as well as by the fine webs they weave on the underside of leaves, a hallmark of their presence.

The life cycle of the spider mite is rapid and highly dependent on climatic conditions, especially temperature. In spring, the females emerge from their winter diapause and begin laying eggs on the underside of the leaves. The larvae, then the nymphs, develop quickly, completing several generations during the summer. High temperatures and dry atmospheres accelerate their reproduction, favouring massive infestations. At Château Cazebonne, we observe them mainly during hot and dry periods, when their activity is most intense. These extreme meteorological conditions can also impact all the fauna in the vineyards.

These mites thrive in dry, warm environments. In our vines at Cazebonne, they preferentially locate themselves on the underside of the leaves, where the microclimate is more stable and protective. They are particularly present on stressed vines or plots with less diversified grass cover. It is therefore fundamental to promote biodiversity to limit their spread.

Although they participate in the general ecosystem of the vineyard, spider mites do not play a direct beneficial role for the vine. Their action is mainly harmful. As sap-suckers, they extract essential nutrients from the leaves, which disrupts photosynthesis. Characteristic symptoms include the appearance of small yellowish or discoloured spots that can evolve into generalised browning, before the leaves take on a bronzed hue, become deformed, and fall prematurely. This water and nutritional stress weakens the vine, impacting the quality and quantity of the future harvest. Their proliferation is also an indicator of an imbalance in the ecosystem, such as too small a population of their natural predators like ladybirds or other predatory mites.

At Château Cazebonne, we meticulously monitor signs of the presence of red spider mites. Rather than resorting to aggressive chemical interventions, our philosophy of sustainable viticulture drives us to favour observation and preventive management. We strive to maintain a natural balance in the vineyard by encouraging the presence of beneficial organisms, such as predatory mites (Typhlodromus pyri, Phytoseiulus persimilis). Proper vine management (pruning, vigour, balanced nutrition) strengthens its natural resistance, which helps to prevent major attacks and supports the overall health of the vine. This comprehensive approach is part of our commitment to pesticide-free vineyards and an agroecology that respects natural balances.

Our commitment is to preserve and enhance an exceptional viticultural heritage, as evidenced by the rehabilitation of forgotten Bordeaux grape varieties, made possible thanks to the support of passionate enthusiasts. To discover these themes in depth, we invite you to download the digital version of the book "Bordeaux, une histoire de cépages", to test your knowledge with our oenological quizzes, or to explore the Cazebonne boutique to taste our wines. To learn more about biodiversity and its protective role in our vineyards, please feel free to consult our section on spiders in the vines.