Springing into Bloom

Spring in Sonoma County

By Bill Klausing
Sonoma County Master Gardener

As the short days of winter come to an end, and the rays of the sun gain in intensity, almost every gardener awaits the first signs of spring on the horizon. The earliest bloomers can catch quite a bit of attention; a few Narcissus pop out of hibernation, Ceanothus begins to show bits of blue, and a few trees burst forth with a fury of blooms to catch your eye.

Pyrus calleryana, or callery pear, is probably the most frequently used early bloomer in landscapes nationwide, and there are certainly a lot of them in Sonoma County. The ‘Bradford’ varietal showed up about 40 years ago, and its relative resistance to fireblight, which had plagued ornamental pears, made it an instant hit. So much so that many landscape designers now have it at the top of their ‘overused’ lists.

Pyrus calleryana is native to China. Its growth habit is moderate to fast; at maturity it reaches 25 to 40 feet, depending on the variety. The shape and relatively moderate size at maturity make this tree a very popular choice in the urban and suburban setting. The canopy is quite pyramidal in form and the leaves are deep green and glossy, which give a very nice fall show of purplish red. However, it is that early spring burst of white blooms that draw most gardeners to this species. And like most early spring bloomers, it can fall prey to those spring frosts, which won’t harm the tree, but will cause dropping of blooms. P. calleryana is also adapted to survive in less than ideal growing conditions. It is drought tolerant once established and can thrive in even heavy clay soils. It is these reasons that keep this species on the list of approved street trees for almost every municipality.

There are drawbacks to Pyrus calleryana though. Many varietals are not quite as resistant to fireblight as once thought, and almost all are somewhat brittle, and are susceptible to splitting at any of the narrow crotches the species is famous for. Needless to say, a strong winter storm can wreak havoc on this tree. Special care in pruning can help minimize this risk, as ridding a specimen of the tightest branch angles during growth can add to its longevity in your landscape. A few new varietals hold promise for more disease resistance, and stronger branching: you might try ‘Chanticleer’, or ‘New Bradford’ if you can find them at your local nursery. I’ve added a sad photo of an old callery pear that I have not yet removed

from my property here in Santa Rosa. You can see what happens after 20 years or so of poor maintenance with the resultant splitting and breaking of branches.

I took a trip to Urban Tree Farm in Fulton and had a brief conversation with manager Alyssa Hall. She recommended that you might try an alternative species of ornamental pear, Pyrus betulifolia ‘Dancer’. It has the same bloomand growth habits of P. calleryana, but offers stronger branching and more disease resistance. Or perhaps you might want to try another of the great early spring bloomers that are available. Malus sp. ‘Prairiefire’ is a smaller specimen (to 20 feet), but displays an intensely pink bloom, with new leaves that are purple in springtime.

Another choice you might want to try is Magnolia x. soulangeana, commonly called saucer magnolia. It grows to roughly the same size as the ornamental Pyrus. It also happens to be one of my personal favorites: I have a young Magnolia hybrid ‘Galaxy’ in my own garden. However, as you drive around the County, and park in many of the shopping center lots, it will be callery pear that you see in full bloom in March!