Rhododendron only flowers on part of plant

[noisycrows]

I have a rhododendron that seems to be two plants together. There is a small, sad-looking part about 1-2ft tall that flowers and currently has plenty of flower buds on it. Coming from the same plant is another stalk (much thicker, maybe 2 inches) that is about 6ft tall, very healthy-looking, but has never flowered and has no buds currently.

What could be going on here? It is in quite a shady spot, but then the small part obvisouly gets much less light than the tall part. Something to do with grafting (if they are grafted, I don't know?!)?!

[nickdub]

It does sound that the plat may have been grafted. The flowering top part being a weaker grower than the rootstock would be one obvious reason for doing this. If so then the stronger growing part will probably flower eventually but in a rather garish pink colour. You could try cutting the stronger part out completely, doing most of the work with secateurs and then tidying up with a sharp knife. You would have to get it all right back to the trunk, else it will just re-grow.

[noisycrows]

Thanks for that nickdub. I have now done a bit of research on grafted rhododendrons and it seems this may be the case. A vigorous rootstock that can send up suckers that will overtake the grafted plant. I think I'll look into cutting that part back.

[nickdub]

You're very welcome - Happy gardening, Nick

[Babru]

This is interesting - I didn't know rhododendrons were ever grafted. Although thinking about it, I have seen standards for sale online, perhaps they're grafted.

[Leslie Simpson]

Interesting. My rhododendron blooms approximately evenly. Of course, the part of the tree on which the shadow from the house falls does not bloom so luxuriantly, but such that part of the tree does not bloom at all has never happened.