Answer: Weigela is a woody shrub; it should never be cut back in the fall. It can be pruned if necessary in late spring right after it blooms. It should not need much if any pruning for the first few years with the exception of removing any winter killed or damaged branches. Be patient with it in the spring because it leafs out a bit late.
Bluemist spirea or Caryopteris should be trimmed back in the spring to remove any winter killed branches and to tidy its shape. Some winters are tougher than others, so you may trim it back anywhere from halfway or down to the ground if necessary.
Hybrid tea roses are always a matter of opinion and to some extent personal preference for pruning, but the pruning is mostly done in the spring. It can be a good idea to trim back the longest canes somewhat to reduce the amount of whipping around in the wind all winter. Do that if the plant is in an exposed or windy location.
In the spring you will remove any winter killed canes, cutting back to live wood. You will also possibly thin the plant to allow better air circulation. A more severe pruning will result in fewer but larger flowers, a more moderate trim will result in more but smaller flowers. Also, on an older plant, you would remove a few of the oldest canes by cutting them at the base. This is done to encourage new vigorous growth. Finally, in spring (and any time you see one beginning) you would also remove any growth coming from below the graft as this would be from the rootstock rather than the hybrid tea variety.
If you have not already done so, late fall is the time to heap soil around the bottom of the canes (make a mound or cone of soil about ten inches tall or so) to protect and insulate the graft union. Use soil from elsewhere in the garden, do not take it from immediately around the plant as this could expose its roots to the cold. You could also mulch over the root area.
Good luck with your plants!
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