We used to have two very knowledgeable posters here, but I think they left with so many other knowledgeable people when I Village acquired this site. I learned much from them, but am far from a viburnum expert.

I don't know the V. nudum cultivar you mention, but I've noticed that a few have started to appear. My pollinator for 'Winterthur' is the straight species. For 'Cardinal Candy', I have a number of other V. dilatum cultivars. Technically, all will self pollinate, but not very well. The correct pollinator will give way more berries.

When V. 'Blue Muffin' (sorry, my mind is not working this early in the morning and I can't remember the species) first appeared in the trade, even the big box stores were selling it, touting all the blue berries. Not without a pollinator, and pollinators for that species remained very hard to find for several years. They're still pretty hard to find, and you dont' get the berries without the pollinator.

Brandywine talk -
Something rarely mentioned in culture requirements for viburnum nudum is it reported dislike of alkaline soils. To what degree of "dislike" I don't know, but I have straight nudum and 'Winterthur' growing in soil I believe to be on the alkaline side of neutral here in SW Ohio - clay soil about 30 inches deep on top of a limestone shelf and in partial shade. Plants seem to be doing OK and fall leaf color is great. Growth could be a tad better, but I'm in no great hurry. I've ordered a Brandywine to add to my collection and to see if I wish to promote it locally in a year or so.

V. dentatum 'Blue Muffin' is the name of that one, laceyvail. The key to cross pollination is overlapping bloom time, not as much as specific plants (although that makes it more likely).

In the situation of V. nudum, you might have 'Winterthur', 'Brandywine' and the straight species in the same garden, but if for some reason they don't bloom at the same time, they will not cross pollinate each other.

In my yard, I have Viburnum dentatum 'Blue Muffin' and Viburnum acerifolium (species) in an area together. For the last two years they have cross pollinated each other because they bloom at the same time. My v. acerifolium never set fruit until I got the 'Blue Muffin'.

So you can try to get the "right" cross pollinators, but there is no guarantee. Good luck, it's worth trying.

Linrose,

'Brandywine' is a plant that's being sold under the Proven Winners brand. It's got good marketing behind it and will most likely be the most common pollinator on the market for 'Winterthur.' It is much more upright growing than 'Winterthur' and not a real match. 'Callaway Small Leaf' is very similar in shape to 'Winterthur' but it's almost impossible to find. From Monrovia Nurseries, 'Earthshades' is another possibility but I think that it'll be hard to find also.

Good Luck,
Ernie