Rhododendrons make for a colourful and attractive display in a home garden, with their showy, trumpet-shaped flowers in a variety of hues. However, they must be maintained if they are to thrive. Proper pruning will result in dependable flowers year after year.
Prune rhododendrons immediately after they have stopped blooming. In most regions, that will occur sometime in June or July. Pruning any later interferes with the following year's buds. Careful timing and planning is essential. Many varieties of rhododendrons exist, with some reaching heights of more than 10 feet. If you plant a type that fits your garden space, you won't have to prune it as much.
When the season to prune arrives, begin by cutting off dead branches and blooms. Inspect for damaged branches that may be diseased. Cut them off to prevent the disease from spreading and to prevent insects from becoming a problem. Prune back any outstanding limbs from the bush, such as stems sticking out from the top, to create a round and trim shape. Do not to cut back too deeply into the plant. A light pruning is all that is needed for rhododendrons to flourish. Snip off withering blooms to keep the plant healthy and attractive. Remember not to prune after July, since it can interfere with next year's blooms.
Rhododendrons have shallow roots, and thus should be mulched to prevent extreme temperatures from reaching them. Covering the soil with "a fairly deep mulch of leaves, pine needles, chips, bark or other organic material will practically eliminate weed growth," according to the American Rhododendron Society. Pull out any weeds, being careful not to uproot the bush. Water rhododendrons regularly, especially in the summer. Their shallow roots can dry out quickly before obvious stress appears.