24-in or 36-inch tall grafted grapevines are premium, greenhouse-grown vines produced using longer rootstock material, which allows them to reach a greater height before shipping. This results in a taller trunk and a more advanced structural starting point at planting, without the vines being older or more mature than standard stock. The added height helps growers quickly establish trunk position and integrate the vines into trellising systems. Compared with standard 12-inch grafted vines, which are produced with shorter rootstock material and start closer to the ground, 36-inch vines offer a faster path toward canopy development and long-term vineyard structure.

However, 24-inch or 36-inch tall grafted vines do not reliably produce grapes earlier simply because they are taller. Their increased height comes from longer rootstock material, not from being older or more physiologically mature. Since they are the same age as 12-inch vines, their fruiting timeline is generally similar.

What can happen: Because 24-in or 36-inch vines begin with a trunk that is already at or near trellis height, growers can establish cordons or training structures more quickly. This can sometimes create the potential for slightly faster vineyard uniformity or earlier training—but it does not automatically translate to earlier fruit production.