Q.Best time to transplant my blueberries
I would like to know when to transplant my blueberries to my backyard from containers because I don’t see them growing and this year I only get 6 blueberries.
There is nothing intrinsically wrong with growing blueberries in containers; indeed, some people prefer to grow them that way, to make sure they have the special acidic soil condition they require. There's a good chance that if you take care of soil, water, and light, your berries will grow, whether they're in containers or the ground. Here are some tips on blueberry growing: https://www.gardeningknowhow.com/edible/fruits/blueberries/growing-blueberry.htm
If you still want to transplant, you might want to consider these basics: https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm