When does a Rhododendron bloom?

The rhododendron is valued for its spectacular flowers, which usually appear in spring. The exact flowering time depends on the variety, weather conditions and the location where it is planted.

Typical flowering period

In general, rhododendrons bloom between April and June. Some early varieties may start flowering at the end of March in mild springs, while late varieties can continue into June.

What influences the flowering time

Variety - there are early, mid-season and late-flowering types.
Temperature - cold springs can delay flowering.
Light exposure - flowering is most reliable in partial shade; strong sun can cause stress.
Soil - rhododendrons prefer acidic soil (low pH), rich in organic matter.

How to encourage richer flowering

Plant in acidic soil or use a substrate for acid-loving plants.
Keep the soil moist but well-drained.
Apply a fertiliser for rhododendrons or azaleas in spring.
Avoid heavy pruning before flowering - flower buds are often formed the year before.