I can see this is an older thread - but hope I might still get some info/advice: I planted a Blue Muffin about 3 years ago - but in a NE exposure in a foundation area at front of my home - as it was just what I wanted for the spot. Its sun is also reduced somewhat from the shadow/overhang of the house. I haven't had any flowers or berries (though I have an arrowhead and some others in my backyard, though unfortunately none on the list of viburnum pollinators in this thread) - though the plant has been in good health. In current circumstances, am I at all likely to get flowers/berries, - or do I need to re-site it? I took a tug at it today with my fork - and the roots seem pretty well-developed. It's also been growing 'straight up' - and I'd like to prune it a bit for some shape at this time - whether it stays where it is or I move it - I assume that won't affect the 'lack of' flowers/berries this year (!); ie, I assume w/o flowers I won't get berries. Thank you for any information or advice those on this forum can offer. 'Much appreciated.

My first two viburnums were two species V. dentatum. In spite of the fact that the tags promised lovely blue berries they bloomed like crazy but alas, no berries. You don't know what I went thru and how many V. dentatums I added to my yard before everything had cross polination. Once it works though, they sure do set alot of fruit. Red Feather does not bloom at the same time as Blue Muffin for me so no berries. Thats why I tossed it. Planted something else.

Your best bet is another clone of V. dentatum. 'Red Feather' is one, but there are a number of others available. BTW, deer seem to prefer V. dentatums to all the other viburnums. Fairweather gardens carries a wide selection of viburnums, but they are finished shipping this spring.

...which is what will happen to those "black twigs". Those are the ends of the pedicels, where the flowers used to be. If the flowers had been pollinated, you would have fruit forming there. The "black stuff" may very well be just the old flower parts that have fallen. They would rub off in flakes. I suggest your plant is perfectly healthy. Post a picture of the whole plant if you can, but I don't believe that there is anything that you need to be worrying about. Other than getting another different Viburnum dentatum clone so that you (and birds) will have ripening fruit to enjoy instead of leftover spent pedicels turning black.