With their airy, showy blooms and deep evergreen foliage, rhododendrons are favourites in many types of gardens. They climb through the years, making them a centrepiece of some garden walls, retaining walls and brick homes. Short-growing types of rhododendrons thrive in sloping rock gardens and other nooks where they can be naturally protected from winds. A few rhododendrons bloom in both spring and fall. Horticulturalists at the University of Missouri say the spectacular flowers make rhododendrons among the most cherished of flowering shrubs.
Check the burlap-wrapped rhododendron root ball or box nursery container for moisture when your plant arrives home. A sustained dry root ball can damage or kill your new plant. Submerge the root ball in water if you cannot plant it right away.
Prepare a planting bed in a sunny site with well-drained, slightly acidic soil. Choose a site where your rhododendron will be sheltered from winds, which dry the soil.
Dig your rhododendron planting bed at least 18 inches deep and 30 inches wide. Keep plants at least 18 inches from the side of the planting bed. If planting more than one rhododendron, give each a separate bed at least 36 inches apart.
Plant the rhododendron root ball so that the tip is slightly above the surrounding earth. Don't cover the root stem with soil. Water the plant well.
Add about 2 inches of wood bark or wood shavings as mulch. Clear the mulch away from the stem of the rhododendron, so that water will seep into the roots. The mulch will help discourage weeds, which will compete with your shrub for water and nutrients.
Remove all weeds by hand if they invade your rhododendron's space. Hoes or spades can destroy a rhododendron's tender, shallow roots.
Replace the mulch completely just before the cold season's first freeze. Keep the mulch from making direct contact with the plant stem.
Maintain a good balance to your rhododendron's soil as the plant matures. Once a year, add a handful of agricultural sulphur to the soil to refresh it.
If weeds are a problem on your property, try laying a few inches of pine needles atop your rhododendron's mulch.
Keep your rhododendron away from trees whose roots are shallow and could invade the planting hole. These include maples, elms and ash trees.