One Solution Doesn’t Fit All
Not All Cultivars Respond Well to Hydrogen Cyanamide
Chill hour accumulation is important for timely and vigorous spring growth in southern highbush blueberry (SHB). Some SHB cultivars exhibit slow or delayed leaf growth and canopy development during emergence from dormancy if grown in low-chill areas under the deciduous production system. Delayed leaf canopy development can result in slower fruit ripening, reduced fruit quality, and plant stress, especially for plants that set a moderate to heavy crop. Hydrogen cyanamide (HC), trade names Dormex™ and BudPro®, is a plant growth regulator that may be a useful tool for stimulating earlier and stronger spring leafing of certain SHB cultivars grown under the deciduous production system in Florida or in other low-chill areas. Where spring leafing is significantly advanced by HC, the harvest season is often earlier and more concentrated than would otherwise occur. Increased berry weight (size) and a slight increase in total yield have also been noted in some cases, but the main advantages are earlier and more concentrated berry harvests.