Getting it to bloom

Why won't my Royal Azalea bloom? (and how to make it flower)

Also called Royal Azalea, Schlippenbach Azalea (Rhododendron schlippenbachii).

More about royal azalea

About Royal Azalea

Rhododendron schlippenbachii · also called Royal Azalea, Schlippenbach Azalea · flowering

One of the most beautiful deciduous azaleas, bearing large, fragrant pale-pink to rose flowers before or alongside the foliage in mid-spring. Native to Korea and Manchuria, it is prized for outstanding autumn leaf colour too. Toxic to dogs, cats, and horses — all parts contain grayanotoxins.

Plant type: flowering

Watch for — Bud blast (Pycnostysanus azaleae): Buds turn brown and dry without opening, often with grey fungal bristles. Caused by the leafhopper-vectored fungus. Control leafhoppers and remove affected buds promptly.

The reasons royal azalea isn't blooming

Almost every non-blooming royal azalea traces back to one of these, roughly in order of how common they are:

Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
The plant has not been deadheaded, so it stops flowering once it sets seed.
Irregular watering — drought or waterlogging at the budding stage makes buds abort.
It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding royal azalea a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get royal azalea to flower

Maximise sun. Give royal azalea the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for royal azalea and get the feeding right with the royal azalea fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Royal Azalea flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full royal azalea care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Royal Azalea blooming — frequently asked questions

Why won't my royal azalea flower?

Royal Azalea blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make royal azalea bloom?

Give royal azalea the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does royal azalea normally bloom?