Hello, heckabore. Normally, pruning after the rhodie has set flower buds would cause your problem. However, since it has not been pruned in 5-6 years, something else is causing the problem. Do you mind answering some questions?

How close is it planted in relation to the other plants, shrubs and/or trees? Can you give us an idea in terms of plant types and inches/feet of separation?

Has the plant ever bloomed... at all? Do you have flower buds now or did the plant not even set buds at all?

If it has buds, how do they look? Healthy? Are they browned out? Do they look like they have hair covering them? (That is a sign of a fungal infection.)

Do you have animals that could eat the flower buds in your city? Deer and squirrels have been known to eat the buds in some locales.

If the plant is not developing buds, how much and when do you fertlize? Could it be getting too much nitrogen directly (when you fertilize it) and indirectly (from lawn fertilizers)?

Normally, you do not need to fertilize rhodies as they feed off the decomposing mulch. But if you have to fertilize due to poor soils or because it is in a pot then the plant could stay busy in growing mode if you apply fertilizers after July or so. July or so is when the plant begins developing flower buds for next year.

Cold weather can be issue but I doubt it would be THE issue for so many years in Zone 9. Moreover, I would have expected it to be an issue for the azaleas too. Very wet conditions could also cause problems during summer so let us know if you normally have cool wet summers.

Lack of sun can also be an issue although I would be suspicious of that if the nearby azaleas are blooming as well as you say.

Is the plant suffering from moisture issues at the time it is developing the flower buds (July-August)? This could be an issue to nearby azaleas but it surprises me that all of them are doing ok. How much and how often do you water during the summer? If they are drowned in water during this critical time, they may be unable to develop buds. Ditto for lack of water.

Soil Ph might be an issue too but it would have affected the other azaleas. Lack of certain micro nutrients in the soil can trigger this behaviour in rhodies but, again, I am surprised that the nearby azaleas have not been affected. When was the last time that you had a soil test?

Lastly and this is not a cop out, I have heard of some varieties of rhododendron that never bloom but I doubt yours would be if the label showed otherwise. People buy them for the foliage. Of course, you did mention that the missing plant label indicated otherwise.

If we cannot figure something out, do not feel obliged to keep this weak specimen. Some plants like roses (Queen Elizabeth for example) sometimes bloom poorly or not all.

Luis

Hi Luis,

Wow! Thanks for the questions and information.

The plant is in a 5-gallon container, planted in a combination of cedar chips, compost, and potting soil. It's only about 18 inches tall (smaller than my smallest azalea). I probably added some peat moss when I put it in there, but I'm not sure. It's fairly heavily shaded and is about a foot away from the azaleas. There is also a hydrangea nearby that blooms OK.

I've actually moved the plant a few times, since I've never been able to get it to bloom. Originally, it was planted in the ground, at the foot of a birch tree, so I dug it up and put it in the pot. I moved it to an area of my yard that has some Japanese maples, so it got a fair amount of sun in the winter and was shaded in the summer. I live in Walnut Creek, and it gets pretty hot here. I moved it to a more protected place, next to my house, last summer.

The plant has never bloomed--it has tiny buds--they are green. they don't have hair. Nothing looks eaten. Our fence keeps away the deer, and my dog scares away the squirrels. I probably gave it some fertilizer when I fertilized my gardenias and the azaleas in February. I can't remember if I've ever fertilized it before. But I do compost, and I've added a layer of compost several times over the last few years.

As far as watering goes, we have sprinklers/drip irrigation that keep it watered in the summer months. During the winter, we let the rain take care of it.

I have heard that rhododendrons are very difficult to grow around here, but I have seen a few blooming in my neighborhood, so I know it's possible. They tend to be huge and are always planted on the north sides of the homes where I see them. I'm looking for a spot on the north side of my house, where I can plant it in the ground.

I used to live in Connecticut, and we had rhododendrons and left them alone, and they were gorgeous. Maybe I'm trying too hard!

Now that Luis has done the detective work -

Too much shade is one of the more common reasons for failure to bloom. Rhododendrons need some sun, or at least bright, open indirect light to produce flower buds.

Also, young rhododendrons will sometimes spend their first years in the garden becoming established, growing root system and framework at the expense of flowers. Moving them can delay bloom for the same reasons. A question often seen here is 'why didn't it bloom, it was blooming when I bought it at the nursery last year'...when the plant has spent those months settling in and not forming flower buds.

While rhododendrons planted in the ground in soil of the correct PH may never require fertilizer, those in containers are dependent on you for regularly scheduled fertilizer applications. In your mild zone, you might want to start in mid Spring and apply once per month for about 4 months. Use a product formulated for acid loving plants that you can mix with water and apply as a liquid - it's usually OK to dilute a little from the package instructions but never go stronger.

It's also a good idea to flush the container periodically to rid the potting mix of a buildup of salts during your dry season. Fill container to the brim with water several times over until it runs freely out of the drainage hole - once a month if your water is alkaline or has high mineral content, every three months if your water quality is good.

Hi, Thanks! I'll try your suggestions. I'm not quite ready to give up on this plant.