Q.Hydrangea
Not getting many heads on our pink ones and my tree hydrangea the head doesn’t open all the way,what fertilizer should I use?

Here are some links that will help you pinpoint the issues.
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-not-blooming.htm
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/growing-hydrangeas-hydrangea-care-guide.htm
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/prune-hydrangea-bushes-hydrangea-pruning-instructions.htm
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/fertilizing-hydrangeas.htm
https://www.gardeningknowhow.com/ornamental/shrubs/shgen/pruning-old-and-new-wood.htm