At first glance I would say the apple juice. Juice is very sweet naturally then when you buy it as a juice it has added sweetners. Maybe a small whole apple processed.
You need to watch out for the no fat stuff..I have looked at the labels and found the carb count much higher on the no or low fat.
I was on this diet plan with LA wiehgt loss and they were on me constantly because I was not getting enough fruit. I tell you the natural fruit killed my readings. A little was ok but man it sure spiked my numbers up.
Like in one setting 1/2 c of blueberries is probably your limit same with the other ingredients like 1/2 c yogart and then 2 oz of apple juice. So the combination may be way too much in one setting. Maybe you could reduce the amounts of each.
Good luck:)

I would agree, between the blueberries and apple juice, and how many carbs was in the yogart>

Another thing I might suggest is looking into a different type of yogurt. I just found this one. It is yoplait fiber one. The container only has 8 grams of net carbs. I don't know how much the yogurt you are using has carb wise, but this is the lowest I have found so far locally.

Sassipean
I would say apple juice, and maybe the the yogurt.

Krogers has a kroger brand yogurt that has only 4 carbs called CarbMaster Yogurt. They have several flavors that are good.
I might cut the Berries down too/ Try each item by it self and see which one or which ones are making your BG high.
I know it is frusrating you think you are going what U are suppose to then this happens. Hang in there. U will figure it out. Good Luck

Thank you so much, never even thought to check the carbs in the yogurt. Tomorrow I will try to make one with some different ingr. other than the yogurt and apple juice.

The yogurt has honey in it. I will be sure to come back and let you know how I make out.