Our native Flowering Dogwood (Cornus florida) is a tree adapted to habitats in semi-shade, such as on the edge of woodlands; in the wild, they are rarely if ever found out in the open. Ideally, they receive some dappled shade during the hottest part of the afternoon in summer. In sunnier locations, they can be more prone to stress and vulnerable to an array of health issues, usually stemming from inadequate soil moisture. (While watering can help alleviate this, often the heavy/compacted soils in our area risk root suffocation if they are kept too wet too often.) Cultivated trees can adapt to full sun (in fact, many at wholesale nurseries are grown in full sun, though they are quite coddled by comparison) with greater attention to care in times of environmental stress. The Asian relative Kousa Dogwood (Cornus kousa) and the hybrids between the two have a bit greater adaptability with regards to sun and environmental stresses.

Dogwoods can be fairly slow-growing, and should be sited in very well-drained soil; an Achilles'-heel of theirs is soil that stays too wet. As with all trees, trunks should be protected from injury from mowers or weed-whackers if the tree will be bordered by lawn; in addition to being an infection risk, on Dogwoods, this wounding can attract a wood-boring insect pest which will cause further damage. If deer visit the grounds, use a trunk guard to prevent similar injuries arising from antler-rubbing in autumn.

Here is an informative page on Flowering Dogwood and some tips for selecting the most appropriate type or cultivar; a number have improved resistance to disease, though pathogen pressures and severity of disease wax and wane from year to year as the weather varies. https://extension.umd.edu/hgic/topics/flowering-dogwood-trees-selection-care-and-management-disease-problems

This is not to suggest that Dogwood is a more problem-prone tree over other options; rather, understanding how best to select and grow them gives them the best chance at avoiding or surviving the widest range of potential issues. Each tree species can have its share of health risks, but proper selection and planting helps to mitigate them. One of the most common hindrances to tree longevity is actually not associated with the tree type but rather to planting technique - often, they are planted too deeply, which affects root health. Trees should be situated in the ground with their root flare at grade (meaning, not sited above or below this point when the soil is back in place and leveled-out). The root flare is the point where the trunk begins to flare-out into root growth, and it usually has become buried too deeply in the nursery pot or burlap ball by the time it is purchased. Removing surface soil from a root ball until this point is located prior to planting will allow you to install it at the correct depth. A crude diagram and brief description of the flare and its importance can be found here: https://extension.umd.edu/hgic/topics/planted-too-deeply and here: https://www.extension.purdue.edu/extmedia/FNR/FNR-FAQ-18-W.pdf While a wide flare won't be very evident on a young tree, the point on the trunk where it is located remains the same throughout its life.

If Dogwood appears to be a less-suitable candidate for your site options, other possibilities for a small-statured flowering tree include: Serviceberry (Amelanchier); Sweetbay Magnolia (Magnolia virginiana) and a handful of other non-native Magnolia species and hybrids; Crabapple (Malus); Fringetree (Chionanthus); Silverbell (Halesia); Snowbell (Styrax); and Redbud (Cercis).

Miri