only one bloom on my rhododendron this year

Portland, OR(Zone 8a)

We planted three fairly large rhododendrons a year ago. They were in bloom at the time. This year, one bloomed beautifully, but the other two did not. Also one of them seems to be a favorite of the slugs. Ever hear of slugs eating a rhododendron? Could they have eaten the flower buds before they had a chance?

Sumner, WA(Zone 8a)

Gosh, I googled on 'rhododendrons' and 'slugs' and got back some contradictions...

Summary of one:
If you've got a lot of slugs and wanted to get rid of them you should grow plants they don't care for, such as hard-leafed evergreens like rhodies.

Summary of the other:
Scalloped (eaten) edges on rhodie leaves could be result of slugs or...

I can't imagine a slug eating one of those buds unless it was miniscule. Is there any evidence of the scalloped edges on the plant?

As for the lack of flowers, you could check the pH of its soil to see if it is lacking some type of rhodedendron-needed nutrient.

....side note...
When I was googling one slug/rhodie topics, I came across this on slug control (well, at least so they have something else to eat...keeping them off of your plants...

"Slugs…get rid of them
Believe it or not…slugs love to eat cardboard! Cut 6" squares of cereal boxes (Special K!), which stay quite firm in wet weather, and place squares near plants the slugs are feasting on. They will congregate under the cardboard, and are then easy to scrape off."

Olympia, WA(Zone 8b)

Well, scrape off or SALT!! hehehe


Albany, OR(Zone 8a)

Slugs do not eat rhodies! Root weevils sure do tho. The scalloped leaves are from the root weevils/beetles.
They are horrible and will kill the rhody evenuately(sp?). So in Oct., you must get some chemical to kills them. Can't do it now. Won't kill anything.
I know, have lost several already and I have only lived in my new place 3 years now.
Those bugs/worms/beetles eat the roots away and then the plants die. It will look like it needs water but watering will do no good.

But on another note, rhodies come and go as far as blooming. They have their good and bad years on blooming. Proper fertilizing is important plus deadheading them too.

But just my 2 cents/experience worth!


Portland, OR(Zone 8a)

Well, the funny thing is I have 3 regular rhodies, one labeled "Hillcrest", one called "Tiana" and one that lost its tag, 2 miniature rhodies and 2 azaelas in the same area, all planted last spring. I also have a very old, healthy camelia there. Everything is absolutely thriving except that "Tiana" and the unlabeled one both have lots of bites out of them, especially Tiana. They are the two that haven't bloomed, but have lots of new leaf growth. Both of these have leaves that are a little fuzzy, not as waxy. Could that be more attractive to slugs or other pests? There is a lot of slug damage in the bedding plants nearby, so I just assumed thats what it was.

Thanks for the cardboard tip, I'll have to try that!

Vancouver, WA(Zone 8a)

I have used beneficial nemetodes for the root weevils. It has been several years now & I have noticed this past week I have them again so will get on it soon.

Northeast, WA(Zone 5a)

Carol is right about the root weavils but I have not heard about the treatment not working except in October. When I lived in Seattle and had them I used a soil dust and dusted around the plant good and it only took one treatment. It didn't matter what time of the year. I did it as soon as I saw the damage.

I never tried the nematodes.

Olympia, WA

This link is to a page on the American Rhododendron Society website.

If you will scroll down to "insects", you will find a no nonsense section on variable ways of dealing w/ the root weevils.


Portland, OR(Zone 8a)

Thanks, everybody! I applied some nematodes and tanglefoot to the bark. I hope that works. I only want to apply pesticide as a very last resort.

Lakewood, WA(Zone 8a)

Tanglefoot will work by killing the adults. The larvae will still be chewing up your roots. But they will morph and become adults, and then get trapped in the tanglefoot so you can definitely win the war this way if you have them on only a couple of plants. If you have notched leaf edges, then it's root weevils. A nastier creature is hard to imagine. Better check your other plants because they eat lots of things, not just rhododendrons. they like azaleas, boxwood, roses, hydrangeas, LOVE mock orange, and also LOVE bergenia. also, there are some cultivars of rhododendrons that they don't seem to bother as much, and some that are irresistible to them.
I have been fighting them for 5 years and I finally think i am winning. I don't like to use pestacides either, but my yard is too big to do otherwise for these creatures. If you end up having to use pesticide (it took me three years to call it quits on organic methods and give up) acephate is what you want. Now I spray only those plants that are being attacked, and I start early in the spring. In fact, I spray only the bottom part of those plants. It seems to be working. I did my usual night time weevil patrol last week and I didn't find any shrubs that were under attack! Yea!!
I have 3/4 acre and they were everywhere!

Portland, OR(Zone 8a)

Good to know. Living in the pacific northwest, I automatically assume slugs. My calla lillies, heuchera and foxglove nearby are getting eaten, too. I've been dropping "sluggo", but I guess that might actually be the root weevils. Hmm, I'm getting closer to breaking down and using poisons. will pesticide hurt the nematodes?

Lakebay, WA

Do root weevils attack boxwoods? I have 2 boxwoods that I put in last year and one is dead now (was green early in the spring) and the other has a lot of green still but is getting browner. Nothing on the leaves/stems that I can see in the daylight and my more mature boxwoods are doing just fine.

Lakewood, WA(Zone 8a)

Yep, they will eat them. But you would see notched edges from a root weevil. That sounds more like maybe root rot, or something else. You would definitely know that something is eating your plant before it died with root weevils.

Joie, it depends on what you use and where you spray it.
I also just had a thought: did you 'deadhead' your rhodies last year? If you did, and you accidently went too far down into the bud area, you may have destroyed the flower buds for this year. Weevils don't generally eat the flower buds. They get the leaves.

Lakebay, WA

You are probably right on the root rot Pixy. When I pulled out the dead boxwood, it came easily away the dirt. I didn't think to look too closely past the leaves as I thought it had been a pest. I planted another boxwood in the same spot, I hope it doesn't suffer a similar fate.

Y'all have a good weekend. 2 hours more of work and then I finally get a weekend off. Hope the traffic isn't bad. I have a loooong commute :-(

Lakewood, WA(Zone 8a)

You might want to treat the soil in that spot with a fungicide, or see if you have poor drainage in that area. Something caused the roots to rot, and many times it's an organism that causes it. Here is some good information to get you started.

If you don't get to the 'root' cause (no pun intended) you may lose the new shrub as well.

Granite Falls, WA

Hi JoieM,

I just came her looking for something else and saw your post. :) I wanted to let you know that this year I didn't get full blooms either.

I have 3 rhodies in the back. One of them had a full bush of blooms. Another had 1/2 with blooms. The other late bloomer only had like 3 on the whole bush. I have a miniature rhodie in front and it had no blooms. These all had full blooms last year.

I did notice what I thought were going to be flowers were in fact new leaves. So the two bushes that had no blooms or 3 are really full of new leaves. The other 2 that had more blooms are slower at seeing new leaves.

Also I read that the buds form this year for the next years bloom season. I didn't know this and last summer I wasn't the best at watering them so much so it is possible they were not creating new buds. Not sure this is it either because I am a novice!!! I think because we have had so much rain fall this year it has really shown me how little I was watering them. :)

So when I deadheaded mine I looked below and could see tiny new buds for next years blooms on the one I had a full bush of. I don't see much on the other yet. Hmmm!!!

Not sure that helps you at all but at least you aren't alone. :)


Portland, OR(Zone 8a)

Yes, I got lots of new foliage this year, too. I had JUST planted the bushes last year and watered them religiously, but it could be that the shock of being transplanted prevented them from forming new flower buds.

Portland, OR(Zone 8a)

Rhodies are very hardy - unless they are planted in too much sun. They are normally in a mixed forest with taller trees for shade. There really should be no reason to ever use chemicals on a fact that can reduce the very bio-diversity that keeps Rhodies healthy! (I agree that Azaleas can be sensitive however...and are less cold-hardy) It is extremely unusual to have blooming problems on a Rhodie in the Pacific NW. Was it just planted and not yet established? Does it get rain in Winter/Spring? (they don't require much in summer. Mulch is helpful to protect/offer shade for those shallow roots)

For the cheapos out there, toss some healthy compost under your rhodies now and then - and you'll probably not need to buy beneficial nematodes either, as enough may come along with the natural bio-swarm present in compost. I also toss handfuls of coffee grounds under, to encourage worms and other beneficial organisms, that help feeed and protect your garden.

I agree that growth buds were probably damaged during deadheading. Still, there would normally be some blooms. Was it just transplanted, or did someone prune off the ends? Pruning is done after bloom is done, and hopefully NOT using that horrid round-ball shearing technique, and don't remove more than 1/3 of the plant per year.

When deadheading Rhodies - don't use shears. Wear gloves that allow fingertip use of a couple fingers. Look closely at each flower base before snapping off spent blooms. You will see 2 or more baby shoots forming along the sides of each spent stem. Bend the stem near the base gently toward the open side where there is no new shoot, and it will snap off correctly. Best not to grab and wrench or you may get the whole leaf whorl. Toss the sticky, spidery cullings into a compost bucket. (If you don't want new growth on a branch due to space, it's ok to selectively bump off the tiny new buds when deadheading)

If your Rhody has not been deadheaded previously, peek in and see the small dead sticks still in the Vees - where the previous years flowers were. Break these off anytime, along with any dead branches under the canopy, to help tidy up the plant. When deadheading, observe how mis-shapen the growth can be in places that were not dead-headed. You get instant results, and a happier plant, so it's worth the time each year the larger Rhodies require for deadheaing. Good Luck.

Portland, OR(Zone 8a)

Well, I'm pretty convinced I had a weevil problem. (more on this thread: I'm not sure if that is related to the not blooming. Its probably two different issues.

Funny thing is, I have never actually SEEN a weevil, but I did find THIS little outlaw in some late night patrolling:

Thumbnail by JoieM
Granite Falls, WA

My 3 rhodies in the back yard were all planted in October 2004 and they bloomed fully in 2005. The miniature one in the front was planted the year prior I think 2003. It bloomed as well. I used compost in the garden and mulched last winter really well.

Oh I just remembered that my neighbor had sprayed chemicals on our fence to seal it. He pressure washed it and then sprayed on the wood sealer and I was so angry. I had told him it was ok to paint our fence on his side but not to spray because I had all my plants there. Well he did it when we weren't aware of it until he was almost done. So I was out there spraying off the bushes for a long time. I was so upset. So maybe that may have caused the buds to be damaged. That was last summer!!! However, like I said the one plant got a full bush of blooms.

When I deadhead them I do it like you said and I haven't ever pruned them. I like the way they look. However, the one that only had 3 blooms and many many leaves is a bit too bushy but will wait and see what happens.

I attached a photo of my miniature one in our front. For some reason I don't have photos of the back. Oh that was when I ran out of film waiting for them to bloom. I now have a digital so I can take some tomorrow.

Thanks for the info...

Thumbnail by budnspuds
Lakewood, WA(Zone 8a)

Joi, you want to see weevils you have to go out at night! All the nasty creatures come out at night! Just go to any plant that has notched edges and shine your flashlight on the leaves. Don't touch the plant until you find one because the minute they feel threatened they play dead and drop to the ground.

I have to agree with pdxjules on everything except : " There really should be no reason to ever use chemicals on a Rhodie..". Have to disagree with that. With 3/4 acre and LOTS of rhodies, and even more weevils, I fought them for 3 years without spraying and finally gave up. That was a good enough reason for me to use a chemical spray. Now that the weevils are under control, I can worry about rebuilding the biodiversity in the soil.

Northeast, WA(Zone 5a)

THAT'S A SLUG!!! I have never seen them on rhodies.

Shawn, I think the other person is right that you probably picked off the new growth when you deadheaded. It is really easy to do. I did that just yesterday on one and I have been tending rhodies for years. So, don't feel bad, just be careful this year.

Strawberry root weevels can be taken care of in several ways. I always just dusted. One application is all I ever needed. Others have their own ways.

Good luck, and don't pick off the little new nubbies.

Granite Falls, WA

Thanks Jnette,

I appreciate your help too! :)


Northeast, WA(Zone 5a)

BTW Shawn, where is Granite Falls?

Granite Falls, WA


That's funny because I was wondering where Ione Wa was. :) Granite Falls is just east of Everett. It is next to Lake Stevens towards the mountains.

Northeast, WA(Zone 5a)

I'm up in the NE corner. About 25 miles south of the Canadian border and, as the crow flies, about 5 miles maybe from Idaho. 40 miles driving.

Spokane, WA

hi, i'm new to this site. i have a question...3 years ago i planted 2 rhodies and they never bloomed! this year one had 1 flower!!! the leaves under the new growth are yellow and brown. they get water every morn. 2 years ago i went and removed what looked like dead buds that didn't open.can someone give me some addvice???

Northeast, WA(Zone 5a)

I don't know what to tell you except if someone on here can't help you, there is a very extensive site by googling Rhododendrons. I have had that happen what you are describing. My advice, if you can't get any anywhere else, would be to fertilize now since it is the right time of year and see if you can't get some new growth out of them.


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