Grapevine plant named ‘BLOMG04’

Latin name of the genus and species:

Cultivar denomination: ‘BLOMG04’.

This application is related to Spanish National Listing no. 20240244, filed Oct. 15, 2024, European Union Plant Breeders Rights Application No. 2024/2402, filed Nov. 5, 2025, and European Union Reference Listing No. 2244015, filed Nov. 4, 2024.

Described herein is a new and distinct variety of seedless grapevine named ‘BLOMG04’. The variety originated from a hybridization performed in Murcia, Spain during 2018 between ‘ITUMNINE’ (U.S. Plant Pat. No. 33,387), as the pollen parent, and ‘15M-121-511’ (unpatented), as the seed parent. Abortive seed traces were embryo cultured, and the resulting plant was planted in an evaluation block during 2019. The first evaluation of the fruit produced by ‘BLOMG04’ was performed during 2020. ‘BLOMG04’ was first asexually propagated by field grafting dormant hardwood scions to 1103 Paulsen rootstock (not patented) in 2021 in Murcia, Spain. Fruit from the resulting six grafted ‘BLOMG04’ vines was first harvested in 2022. All characteristics and distinctions remain true to form and are established and transmitted through succeeding propagations.

The following are the most outstanding and distinguishing characteristics of ‘BLOMG04’. ‘BLOMG04’ produces naturally large (6.5 g/berry) seedless violet (5RP3/2) berries, with colored flesh (5R3/4), a crunchy and firm texture, a cylindrical shape, with an excellent neutral flavor with a good balance between sugar-acid neutral, and a high fertility index (1.3), that are harvested in late August, in Murcia, Spain.

‘BLOMG04’ is believed to be most similar to ‘Blagratwo’ (not patented). Nonetheless, the new cultivar can be distinguished from ‘Blagratwo’ based at least upon berry shape, berry flesh color and berry skin color. The berries produced by ‘BLOMG04’ have a cylindrical shape while the berries produced by ‘Blagratwo’ have an obovoid shape; and the berries of ‘BLOMG04’ are violet and have coloured flesh while the berries of ‘Blagratwo’ are blue black and the flesh is not pigmented.

‘BLOMG04’ can be distinguished from its male parent, ‘ITHUMNINE’ (U.S. Plant Pat. No. 33,387), in that the new cultivar produces berries with colored flesh while the berries produced by ‘ITHUMNINE’ do not have pigmented flesh. The berry skin of ‘BLOMG04’ is thinner than that of ‘ITHUMNINE’.

‘BLOMG04’ can be distinguished from its female parent, ‘15M-121-511’ (unpatented), in that the new cultivar, ‘BLOMG04’, produces seedless grapes while ‘15M-121-511’ produces seeded grapes. The bunches produced by ‘BLOMG04’ are heavier than the bunches produced by ‘15M-121-511’. The berries of ‘BLOMG04’ have a crunchy and firm texture where the berries of ‘15M-121-511’ have a soft texture.

The following detailed description sets forth the distinctive characteristics of ‘BLOMG04’. The detailed description was obtained between March and November using 4-year-old plants grown in the field in Murcia, Spain. The color references are to the Munsell Plant Tissue Color Book, 2012 Edition by Munsell Color.