To keep it simple, the general rule of thumb for pruning flowering shrubs, is to prune immediately after flowering. If you prune later, you will be pruning off next year’s flower buds.
If flowering shrubs bloom on new wood (this year’s growth), then you can prune in spring.
For some shrubs, plants bloom on new and old growth, such as some newer cultivars of Hydrangeas. These shrubs don’t necessarily need pruning, unless you are pruning off wayward branches or controlling size. In this case, it’s best to prune the oldest branches out. You will still get some bloom then on the new growth.
If you learn the names of your plants, you can always contact us for information on individual plants. Often we need the full name – the family name and the variety.