Key facts to get the most from a rhododendron

October 9, 2015

Rhododendrons bring beauty to the spring garden. The pink flowers set against the green leaves adds dimensions to a yard that an ordinary shrub can't provide. Here is what you need to know from buying to growing a rhododendron.

Key facts to get the most from a rhododendron

Basic facts about Rhododendron

  • Their thick, leathery, evergreen leaves vary from 8 to 15 centimetres (3.25 inches to 6 inches) long and are carried on woody branches that form elegant tiers.
  • Tubular flowers adorn the stem tips in late spring and ealry summer. Each set off by a frame of green leaves.
  • Flower colours include purple, red, white, yellow, and pink.
  • Plant large rhododendrons for a privacy screen or boundary marker and use compact types along paths or in foundation plantings.
  • Site them carefully, so that their brittle limbs won't spread into high-traffic areas.
  • Fill the foreground of the plantings with a shade-loving groundcover, such as ferns or lamium.
  • Rhododendrons also enjoy the company of their fellow woodland plants, including dogwood and mountain laurel.

Pro tips to properly grow rhododendron

  • Select a site with filtered shade, or one with morning sun and afternoon shade.Plants growing in deep shade may grow leggy and flower poorly, while those in sun will show scorched leaves.
  • Protect against strong wind, which can shred the leaves.
  • Rhododendrons need loose, moist soil with a pH of 4.5 to 6.0, so prepare a roomy planting hole amended with acidic leaf mold or peat moss.
  • Plant in spring and set plants high, so that the topmost roots are barely covered with soil.
  • Spread eight centimetres (3.25 inches) of compost, bark chips, or other organic mulch over the roots.
  • Water only as needed to keep the soil barely moist. Too much water leads to incurable root rot.

Potential problems

Rhododendrons are susceptible to certain bugs that can affect its health. To fix it follow these steps:

  • Occasional problems with die-back, which causes branch tips to blacken and die, are caused by burrowing caterpillars called borers and by fungal disease: Cut back affected stems to healthy wood and dispose of the damaged portions.
  • Lacebugs are the likely culprit if you see yellow splotches on leaf surfaces and insect excrement on leaf undersides: Spray plants with insecticidal soap per label and dispose of fallen leaves to remove the insects' nesting places.

Selecting rhododendrons

There are thousands of species and cultivars, ranging in height from 60 centimetres to three metres (25 inches to 10 feet). Most are hardy from Zone 6, although some Ironclad hybrids are hardy to Zone 4. .Among smaller types, look for Yako rhododendrons (R. yakushimanum [Z5]), a Japanese native that forms a rounded plant with felted young leaves. Two good North American species are the Carolina (R. carolinianum [Z5]) and catawba rhododendrons (R. catawbiense [Z4]), both with purplish flowers.

Fundamental facts

The large flowers and leathery leaves make this an eye-pleasing shrub and that it can live for decades makes it easy to care for.

The material on this website is provided for entertainment, informational and educational purposes only and should never act as a substitute to the advice of an applicable professional. Use of this website is subject to our terms of use and privacy policy.
Close menu