Community - Organic Pathways - Your Online Guide to Organics in Aotearoa New Zealand

Resistant rootstocks are the only completely effective means for phylloxera control in the most severely affected areas.
Destroy any affected leaves, including those on the ground. Also ensure good hygiene by clearing away surrounding area of weeds
Encourage natural predators - these include ladybirds, lacewings and wasps, ie Encarsia and also pathogenic fungi.
Refer to this page on aphids for some natural sprays. Phylloxera are closely related to aphids - or use sticky yellow boards.
If your grape vine is suffering from a magnesium or phosphorus deficiency, it will be more susceptible to attack.
Check these links for more info on the Encarsia wasp: http://www.organicpathways.co.nz/AnswerFile.cfm?QuestionID=149 and http://www.organicpathways.co.nz/AnswerFile.cfm?QuestionID=15