Pruning right after your rhododendron finishes blooming can be done, with a light hand, by clipping off any faded blooms and extra long branches. You can thin and trim, removing up to one third of the shrub. Rhododendrons do not need to be pruned to keep them healthy. Pruning is just to control size and shape. For more vigorous growth make sure your rhododendron gets plenty of water in August and September when the plant is setting next year's flower buds. Rich soil that is dark with organic matter will also make Rhodies grow fast. Another tip is to not plant these shrubs too deep. Just barely cover the top of the root ball with a bark mulch. Keep growing, Marianne Binetti