Now that flowering is over, the stalks are covered with the remains of the flowers. Do I cut off all the stalks that flowered, and when?
The best time to prune your weigela is right after it has flowered, as it blooms on one-year old wood. You can cut off the stalks that flowered, as well as branches to maintain an attractive shape.
It can be pruned quite hard: up to 1/3 of the oldest branches can be pruned to the ground and other branches cut back to the height you wish to maintain.
If you don’t prune the bush will become shrubby; if you wait too long before you prune you will not get flowers the next year.