Q.why are my blueberries bitter this year when normally sweet?
Wre my blueberries bitter this year when normally sweet?

Certified GKH Gardening Expert
For sweeter berries, allow them to remain on the bush a little longer. Otherwise, they may not be fully ripened. Look for a dark navel when harvesting blueberries, not the color of the fruit. Blueberries with a reddish color aroundthe stem end are not ripe, and will be tart whereas those left on the bush to become fully deep blue will be ripe and sweet.
Also, it may help to raise the soil acidity. This article should help with additional suggestions: https://www.gardeningknowhow.com/edible/fruits/blueberries/lower-soil-ph-blueberries.htm