What do I need to do for sweeter blueberries? Last year they were very sweet, and this year they are very tart.
Certified GKH Gardening Expert
A common complaint with these plants is sour tasting berries. However, most people actually harvest their blueberries too early. 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 around the 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.
Raising soil acidity can also help. Pine needle mulch will help raise the soil acidity over time, but there are some other things you can try too. This article should help with additional suggestions: https://www.gardeningknowhow.com/edible/fruits/blueberries/lower-soil-ph-blueberries.htm