Dogwoods are certainly pretty as they bloom this time of year. They are rare, but seen often enough in nurseries to make one wonder why they are even more scarce in local gardens. Those that got sold in previous years should now be prominent features around town. The problem is that because they are not happy in local climates, dogwoods become dogwon’ts. They won’t bloom. They won’t provide good fall color. Many won’t even grow. Dogwoods prefer more humidity, so in local gardens, want to be sheltered from full sun exposure and drying wind by larger trees or buildings.
Nurseries generally stock plants that are appropriate for local climates. A few nurseries also have a few plants that would rather be somewhere else, but can be grown with certain accommodations. Reputable retail nurseries are generally careful to divulge which plants need more attention, and what their requirements are. However, many of the big garden centers in home improvement stores are more interested in selling what they can rather than selling what is actually appropriate, particularly since they thrive on turnover and replacing plants that do not survive.
Not all plants are as easy to grow as junipers and oleanders are. Japanese maples and rhododendrons like at least some degree of shelter from direct sun exposure and dry heat; but the California fan palm thrives in wicked heat. Plumerias and coleus can be damaged by even slight frost; but many apples and pears want more frost. Spruces like even moisture; but many yuccas rot without enough dry time.
This is why it is important to know how to accommodate plants that may be less than ideal for local climates. Those of us who choose to grow plants that have special needs should at least give them what they want if we expect them to perform as we want them to.
highlight: American dogwood
The state tree of Missouri produces the state flower of North Carolina, which are both the state tree and state flower of Virginia, but no so exploited by the state that it seems to be named for! The American dogwood, Cornus florida, is such a classic American tree that last year, young trees were given to Japan to commemorate the gift of Japanese flowering cherry trees from Japan a century earlier.
Profuse early spring bloom is not what it seems to be. Tight clusters of minute flowers would not be much to look at, but are surrounded by four big white bracts (modified leaves) that really put on an impressive show before green leaves develop. Many modern varieties have pink or nearly brick red bracts, and a few get variegated foliage as bloom dissipates. Foliage can get quite colorful just before it falls in autumn.
In the wild, American dogwoods are ‘understory’ trees that are happiest in forests of larger trees that shelter them from harsh sun exposure and drying wind. In relatively arid western climates, they want rich soil, regular watering and partial shade at least after noon. They are sensitive to reflected glare and wind, as well as alkalinity and salinity. (Too much fertilizer will roast the foliage.) Since American dogwood trees rarely get more than fifteen feet tall in cultivation, they are proportionate to sheltered atriums. Wild trees do not get much taller than thirty feet.