Q.Transplanting Spiraea shrub
I have 4 spireaea shrubs which bloom in the late spring and want to move them to make an accent around my fence. The ground is mostly clay. Do I need to do anything to the soil and what if any fertilizer do I need?

Whenever possible transplant your Spirea in the late winer or early spring before the new growth begins.
If they need to be moved after they have begin growing, you can prune back the plant by 1/3 to help with transplant shock.
Water the plant well in the 48 hours before digging and moving and make sure you provide plenty of water to the shrubs after moving.
Place them in the new planting hole at the same depth.
Spirea will tolerare clay soil conditions.
https://www.gardeningknowhow.com/ornamental/shrubs/spirea/growing-spirea-shrubs.htm