Grapevine red blotch virus (GRBV) is a member of the genus Grablovirus, in the family Geminiviridae. GRBV is the causative agent of red blotch disease, a significant threat to grape production in North America identified in the 2010s. GRBV is primarily disseminated via infected planting material and grafting, though secondary spread has been noted in vineyards in northern California and southern Oregon. Significant work has centered on the identification of vector candidates of GRBV. We conducted studies in the greenhouse using one such candidate, Spissistilus festinus, to assess the mode of transmission of GRBV. Aiding in these efforts was the identification of snapbean, Phaseolus vulgaris, as a pseudo-systemic host of GRBV and alfalfa, Medicago sativa, as a nonhost of the virus. We determined the transmission of GRBV to be circulative and non-propagative. Furthermore, we determined the time required for GRBV to be identified in the salivary glands of the treehopper varied based on donor host, six days on infected bean plants and 10 days on infected grapevines, following a 48 hour gut clearing period. This information was used to assess the transmission capabilities of S. festinus in the vineyard. We determined S. festinus can acquire GRBV from infected, cultivated grapevines in a diseased vineyard and that transmission is facilitated by fewer viruliferous insects feeding on less tissue of healthy grapevines. Continued surveys of two California vineyards determined secondary spread occurring at rates likely related to the abundance of S. festinus. Furthermore, identifying the phylogenetic clade of the GRBV isolate infecting diseased grapevines indicated aggregations of non-dominant clades in diseased vineyards, suggesting that planting stocks were the inoculum source. We showed that when infected scion material was used at planting, red blotch disease symptoms are apparent one year post planting, but symptoms may take 3-5 years when the infection source is the rootstock. Among infected grapevines, we demonstrated there is no significant difference in the number of GRBV copies in grapevines that have been symptomatic for one to six years in June (when vines are asymptomatic) or in October (when vines are symptomatic). We confirmed the trend of increasing virus titer in grapevines over the course of the growing season in infected ‘Merlot’ and ‘Cabernet franc’ vines in New York and California vineyards. This was not observed in ‘Cabernet Sauvignon’ grapevines in Georgia and California vineyards in which no differences in titer were recorded between June and October sampling. With past work focusing on the California (CA) genotype of S. festinus, we documented that the other known genotype, the Southeast (SE), is also capable of transmitting GRBV. Moreover, the SE genotype transmits GRBV at a higher rate and sustains a more efficient virus acquisition to the salivary glands than the CA genotype. Controlled mating experiments confirmed the two genotypes are capable of reproducing, indicating they are indeed different genotypes of the same species. These studies demonstrate that the epidemiology and transmission biology of GRBV by S. festinus is unique. This work has proved invaluable for informing disease management recommendations focused on the use of GRBV-tested planting material, particularly the rootstock, rather than implementing vector control solutions.