Almost certainly those are seed grown trees, and assuming that is in fact the case, you may be waiting a few more years. Seed grown trees have to mature for a number of years (only they know how many) before they will flower. A grafted tree, takes a branch of another tree that becomes attached to the rootstock (another probable seed grown tree). This grafted portion "knows" that it is already some years old genetically, and therefore will begin flowering earlier. You likely seed grown tree will flower, but nobody can say how long that will be. BTW, flower buds are set in late summer the year before flowering, so you can examine your tree in the fall and determine if it will likely flower the following spring. The flower buds look kinda like an teardrop shaped onion in shape.You can find pictures on the net. Arktrees

Thanks a lot, gardengal. I've looked at descriptions of all three of those on VA Tech's vTree site. The fruit clusters looked similar enough that I was convinced it had to be a dogwood, but various details didn't seem quite right. vTree describes C. sericea as having bright red twigs, and I think I would have noticed that, but I don't remember the twigs being a special color like that. The bloom time seems too late for C. sericea and C. alba. C. sericea, C. alba, and C. racemosa are all described as shrub or thicket-like in form, and my friend's trees looked very tree-like, even a little lanky, almost like our native serviceberry. My friend and I both mistook the trees for cherries at first, like young P. serotina. If that's any help, the bark looked enough like cherry bark to fool a couple guys that are pretty familiar with most of the common native trees. C. sericea, C. alba, and C. racemosa are respectively described on the vTree site as up to 15, up to 6, and up to 10 feet tall but all generally shorter, and I'd say these trees were 15' or taller. It just seems like too many details don't quite fit. None of the options seem to fit the form. Could I be off altogether on the dogwood assumption? Are there other dogwood species that could be options? If not and assuming it's a dogwood, I'd have to lean toward C. sericea for height but not for the twig color and bloom time. C. racemosa seems closer to the right bloom time and the bark and twigs don't seem off (based on my rough memory), but the height and form seem too far off.

It is not entirely uncommon for a spring or summer blooming plant to throw scattered out of season blooms. Generally, the off season flowering is prompted by stresses during the growing season - periods of drought or even excessive rains, colder/hotter than normal temperatures, etc. This throws off the plant's internal mechanisms that control flowering and when temperatures and/or rainfall combine to repeat conditions that typically are present during the normal bloom time, the plant will mistakenly produce flowers in response to these conditions. It is not usually a big deal and offers some colorful enjoyment out of season. If the bloom is heavy on fruiting plants - crabapples come to mind as they will often respond to these situations with out of season bloom - flowering during the following normal bloom season may be off or slight, affecting the ability to produce fruit. Parts of Texas are seeing quite a bit of this unseasonal flower production in the aftermath of Hurricane Ike, obviously a serious plant stressor.

Cherries are a week to 10 days IME, redbuds only a bit longer, and dogwoods the longest. Kousa dogwoods in my yard bloom densely for a month to 5 weeks if you include the early small chartreuse bracts that are there before they become white and fully formed. Cherries, redbuds, and Cornus florida bloom on bare branches while Cornus kousa start blooming as the leaves are finishing emerging and continue with fully formed leaves. It's been so long since I had a Cornus florida that I don't remember bloom length, but because the ornamental part of the flower is actually bracts on these two dogwoods, the "petals" last longer. Cornus alternifolia, the local native dogwood, doesn't have the bracts and the blooms are more in line timewise with the cherry and redbuds. Look also at frost resistance and timing of blooms since your near-ocean location can make for cold late in spring, which can make flowers last longer if it stays above freezing or it might kill them with a frost. Consider also other season appeal. Fall color is clear yellow on redbud, deep red and late on my C. kousa, peach-like on my C. alternifolia with sun, and a somewhat muddy yellow on my cherries, though that varies some on location, species, and individual plant. Look at winter silhouettte (nicer to my eye on weeping cherries and dogwoods) as well as bark (shiny on some cherries). Fruit can attract birds, and depending on the appeal of the fruit, can add color and movement anywhere from August to spring. Kousa dogwood June 1, just starting to show chartreuse. Although this is a terrible photo, I really like this phase. June 12 whiter, less green June 22 fully white and I have a photo from the same year on 6/29 still looking like this. By mid-July flowers are gone and fruits are just starting to develop. When it fruits, they are about the diameter of a quarter or a bit larger, like one of the larger ornamental crabs. We don't have many gray squirrels here, but this one kept me entertained for a couple of hours one March afternoon. I would guess that Kousa fruits aren't favored food, but they are edible, both for the critters and for us. The winter flower buds make me think of Russian church spires, and the layered effect of branches looks good.