Why do most vineyards have rose bushes at the end of the vine rows?
Answer From Expert Roger Bohmrich MW
Other than the intrinsic beauty of roses, which add a beautiful splash of red amongst the green foliage of a vineyard, the reason that rose bushes have been planted at the end of vine rows is that they act as a "canary in a coal mine" for grape growers. The rose bush and grapevine are susceptible to some of the same destructive maladies, particularly cryptogamic diseases like powdery and downy mildew. Both are also attacked by aphids. Roses tend to be affected earlier than nearby vines, thus serving to alert the vineyard caretaker that preventive treatments may need to be applied.