Its aromatic, "labrusca" flavor is similar to that of Concord, but mellowed by the mild, sweet taste from Thompson Seedless.

Thomcord grows well in hot, dry climates, ripens between late July and mid-August, and tolerates powdery mildew.

[2][4] Compared with Thompson Seedless, the berry weight and diameter of Thomcord are larger, but cluster tightness is similar.

The fruit's size has not been shown to increase appreciably by girdling the vines or by applying gibberellic acid when the berries set.

[2] The aborted seeds of Thomcord are small, but in some years they can become sclerified (a thickening and lignification of the walls of plant cells and the subsequent dying off of the protoplasts), making them more noticeable inside the medium-soft flesh.

The teeth on the edge of the leaf blade are convex on both sides, medium in size, and short relative to their width.

Young shoots are fully open and have very dense hairs of medium anthocyanin coloration that lie flat against the tip.

[2] In 1983,[4] research horticulturist David W. Ramming and technician Ronald L. Tarailo—Californian grape breeders working for the ARS, the chief scientific research agency of the USDA—crossed Thompson Seedless and Concord in order to answer a technical question about a newly developed procedure for breeding novel, superior seedless grapes.

[3] The researchers wanted to demonstrate that plants created from embryo culture were derived from fertilized eggs (zygotic) instead of the maternal tissue (somatic).

[2] From 1231 emasculations (removal of male flower parts to control pollination) of Thompson Seedless, the researchers produced 130 ovules using embryo rescue procedures.

[2] It was later selected in 1986 by Ramming and Tarailo and tested in the San Joaquin Valley under the name A29-67, and was introduced as "Thomcord.

[2] The Foundation Plant Services (FPS) at the University of California, Davis indexed Thomcord and found it to be free of known viruses.