Thanks for such a well-written explanation! I purchased viburnum trilobum compactum plants from Forestfarm several years ago-- and although they survived for ten years or longer, they never did anything. Now I understand why they never produced fruit . . . but actually, they barely even bloomed! I finally gave up and pulled them out this spring. Very disappointing. As to why plants of different provenance bloom at different times even if they are of the same species, maybe you could think of it this way: every species has some genetic variability within the species. A group of specimens growing in a certain area would tend to produce seedlings that bloomed at several different times. However, the seedlings that bloomed at the best time for that location would have a natural advantage over the seedlings that bloomed a little too early, or a little too late. Therefore, by natural selection, the bloom time that is best for the area would eventually become the most commonly found genetically-programmed bloom time amongst plants in that area. In other words, the gene pool of seedlings in that location would have been narrowed. Similarly, seedlings from a different part of the country would slowly narrow their genetic pool to reflect whatever bloom time is best for their location. When you then order plants from the two different locations, even though you are now growing them in identical conditions, their bloom times will continue to be influenced by their genetic programming as well as their current growing conditions-- and this will be true for as long as those two plants live, even if they are growing side-by-side. Does that make sense? I realize that I'm not explaining it very clearly. :( (Maybe another way to understand it is to think about humans: we are all one species, but we look a lot different according to our ethnic backgrounds because when groups of people were isolated geographically from other groups, an unusual or recessive trait-- red hair, for example-- had the opportunity of becoming very common within that specific isolated population.)

Hi tricitiestn: A friend of mine - to whom I recommended V. dentatum Indian Summer™ - went googling and found this thread, and noted that I had contributed information. She suggested I take a look. I left this forum (GardenWeb) in 2006, when it was under previous management and not exactly the most user-friendly environment. Still, lots of good viburnum information was generated and shared - and carried forward lo these 15 years! I appreciate that you and others find value in it, keep these threads alive, and add to the overall community knowledge. I like your list, and think you ought to keep punching it up. I wonder if we have conversed on forums on other sites (DG, NGA) where I frequent these days. Same screen name, same irascible but focused commentary. You will note in those older posts that both Kevin and I had listed some very young/very recently acquired plants, and noted that those selections had not yet settled into our growing zone and climate variations. We also noted the obvious: sometimes you get mislabeled plants! Many gardeners know the disappointment of buying, planting, and waiting for that odd variation of the common to grow and bloom - only to find that it was an imposter and no different than what you already had. Caveat emptor, I think. I found, not long after the posts above, that my plants labeled Chicago Lustre and Autumn Jazz were reversed - and that enlightenment came about by continued conversations with authorities like Gary Ladman, Kevin, and other viburnum enthusiasts. The common denominator is that we want to get it right while providing positive factual information about these clones that come from all kinds of different provenances, That way, gardeners can wade through the hype of sellers and glean actual performance information from fellow gardeners, and hopefully in as similar a circumstance as possible. Other changes since this thread started: great growers like Roy Klehm who trialed and selected so many of the treasured selections on this list - are no longer in business, and many/all of his named selections are no longer regularly available. That is tragic. Gary Ladman is no longer the young pup he once was (who is?), and being out in Nebraska makes it tough to widely disseminate his great plants and voluminous knowledge of the genus. Kevin no longer resides in west suburban Chicago, and that is a great loss to the upper Midwest gardening crowd. He is now in the hinterlands of the Appalachians, not particularly far from tricitiestn - which means that they will cancel each other out with redundant information (!!!). Actually, he is so glad to be growing in a balmy climate that he is transitioning into all the evergreen and south of zone 7 species that he routinely killed up in zone 5. I guess I alone am the constant, the touchstone, for the central KY Bluegrass country in the zone 5a - 6b range of the Ohio River valley region. -30ºF temperatures in early 2015 rocked the decades-long collection of plants here at Viburnum Valley Farm, and a couple of severe droughts afflicted those stressed plants that survived those severe temperatures. Ice storms and snow loads, cicadas and other biblical plagues have also taken their toll. Still, the test is the point. What I enjoy daily around these 10 acres that I've cultivated since 1990, are the stalwart citizens of my plant world that I will continue to expound upon on forums like this. There are new selections that continue to be added, and mature residents will pass on to the great compost or brushpile in the sky, to be renewed in the vascular systems and bloom clusters of future viburnums. I hope all here, and generations to come, will continue to contribute their experiences and opinions; listen, process, and evaluate writings of others; and keep seeking more information to grow more plants successfully for improvement of our landscapes and overall environment - and inspire succeeding generations to do more of the same. ViburnumValley

I purchased seedlings of Viburnum recognitum (northern Arrowwood) and V. lentago from the NH State Nursery 4 years ago. They are about 5 years old now and haven't bloomed yet. From what I understand, Viburnums are self-sterile and require 2 genetically different individuals to pollinate. I am looking forward to the first blooms and berries. I also inherited several specimens of Viburnum carlesii, both the tall variety and a couple 'Compactum'. They are so fragrant, however, all but one died after I transplanted them! The previous owner planted them in inappropriate places (like just about everything else!) I wonder if the non-native Viburnums are very fussy?

Actually POPCORN is flowering now. It always gets my attention in flowqer because of the huge white flower clusters. Since my other viburnums were all selected for fruit production they look good flowering but not as showey as POPCORN. Shoshoni started flowering heavily as it added afew more years, it just needed to grow up some. Shasta always flowers heavily now and both set fruit for me each year. Shasta is about 7 feet and Shoshoni about 5 feet tall. I don't know about wide because if they get too wide, I just prune back some branches. Over all, I am very glad that I planted all three of them and here they stay.