Rose of Sharon (Hibiscus syriacus) can be pruned back hard in early spring to produce good bloom later in the season. You don't say what kind of holly you have. If it is an evergreen,
English holly type, there is no need to prune at all. Small leaved Japanese holly (Ilex crenata) that is used for hedges can be
pruned hard if necessary when the new growth has become woody. Winterberry (I. verticillata), our native deciduous holly does not require pruning except to tame wayward branches which can be cut as necessary.