Grapes treated with ABA plant growth regulator ProTone


ProTone® contains s-abscisic acid (ABA), a plant growth regulator found naturally in plants. ProTone enhances color development in red table grapes by initiating the rapid accumulation of red pigments into the skin of the berries. ProTone-treated grapes have a natural appearance and maintain good quality at harvest and throughout shipping and storage.

ProTone can be used to initiate earlier harvest, increase overall marketable yield, and/or reduce the number of picks within a particular block. It can be applied from the time of veraison to late in the season. The optimal timing for a particular block will depend on the cultivar and the harvest management objective. While most early season applications of ProTone are effective in developing marketable color, late season applications are also very effective in most cultivars, even after sugar development has occurred.

ProTone works well with ethephon in an integrated coloring program. Ethephon will increase ethylene gas production, spurring ripening, while ProTone will trigger coloring only. Note that ProTone does not translocate throughout the fruit; for optimal product efficacy ProTone needs to be applied directly to the fruiting cluster and complete coverage of berries is essential.

With ProTone, growers can accelerate and better manage their harvest to peak at times when prices are high for premium grapes. Red table grapes can be colored earlier and more evenly for greater packout and more flexible yield without compromising pre- or postharvest quality.


ProTone SG is a 20% soluble granule formulation

ProTone SL is a 10% liquid formulation.

Always read and follow the label instructions when using any VBC product.

ProTone Information
ProTone Grapes
Red table grapes treated with ProTone
ProTone Chart


Product Literature