Winegrowers on the Canary Islands Fear the Worst as Phylloxera Takes Root

One of the world’s most dreaded vineyard pests is threatening 500 years of traditional viticulture on the Canary Islands. Grapegrowers discovered the first-ever confirmed cases of phylloxera on the volcanic archipelago earlier this month. Vineyards in three towns on Tenerife, the largest and most populous of the islands, tested positive for the root louse, leaving winemakers and officials on edge as a response is organized.

The islands are a volcanic archipelago, located off the coast of Morocco and politically a part of Spain. Nearly all the islands’ vines grow on their own roots, which leaves them particularly susceptible to the deadly insect. Most Vitis vinifera vines are grafted onto American rootstocks, the only known method of growing winemaking grapes safely in afflicted areas. However, the Canaries’ volcanic soils, as well as the rapid response from its winemaking community and government, could offer reasons for hope.

The first sign of phylloxera was detected in late July on a private vineyard in Valle de Guerra, on Tenerife’s northern coast. The small town has been at the center of the outbreak, home to most of the confirmed cases, primarily in abandoned vineyards. The other two cases are in nearby towns, though these seem to be smaller and more isolated. While monitoring is ongoing, a total of 697 sites have been tested so far, with 30 containing phylloxera, according to the island’s agriculture agency and the Tenerife Island Council, the two governing bodies that have been managing the response.

Soil as a Natural Defense

Until now, the chain of islands that make up the Canaries had not been infected by phylloxera, thanks to its isolation and volcanic soils, which can be inhospitable to the pest. (Similarly, ungrafted vinifera vines grow with little fear of infestation on parts of Sicily’s Mount Etna and Greece’s Santorini, for example, due to sandy, volcanic soils.) Local growers are taking hope from that. The Association of Winegrowers and Winemakers of the Canary Islands (AVIBO) released a report that mentions the possibility that these soils could limit infestation or even lead to the insect’s disappearance.

Envínate winemaker Roberto Santana, who has been making wine on Tenerife since 2008, echoed a mix of anxiety and hopefulness. “We are very worried, but we think that the phylloxera in the volcanic soils of the island are not going to [spread],” he told Wine Spectator. “One important thing is that the vines that have been [infected] are from abandoned vineyards. [The few infected vines] only have the phylloxera in the leaves, not in the roots, which is really important right now.”

But phylloxera spreads easily, sometimes when the insect takes on a winged form during its life cycle. In addition to the bug’s natural ability to proliferate, the timing of the infestation—right at the beginning of harvest, when plant material is on the move—could exacerbate the spread. Both the AVIBO report and Canarian government officials have supported the idea of prohibiting the transport of grapes among islands and areas within islands, but no law has been passed yet.

[article-img-container][src=2025-08/ns_canary-vines-pests-palo-blanco-082125_1600.jpg] [credit= (Courtesy Robert Santana) ] [alt= Century-old Listan Palo vines for Envínate on the island of Tenerife.][end: article-img-container]

Ancient Vines, Special Terroir

If containment fails, Santana fears it could “practically end viticulture in Tenerife.” The islands are known for their uncommon grape varieties grown in historical methods like cordon trenzado, where branches are braided together and grown horizontally, capable of reaching more than 30 feet in length. Many of these ungrafted vines have developed in the islands’ terroir for centuries, occupying an irreplaceable niche in the wine world.

Though there is no known formula for eradicating phylloxera completely, grafting Vitis vinifera onto the rootstocks of American grapevine species that have defenses against phylloxera, like Vitis riparia or Vitis rupestris, is a reliable method of replanting and keeping vines healthy. Are grafted Canary Island wines possible? Technically yes, though the rugged topography and atomized nature of the many small, family-run operations of the islands makes this difficult to envision.

As Santana points out, “perhaps … [but this] would completely change the landscape and the wines we have today.” Preserving all the unusual grape varieties and historic growing methods would be difficult.

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