Magnolia roulette….dodging the frosty bullet

Posted March 29, 2011 by Panayoti Kelaidis, Senior Curator & Director of Outreach

Closeup of star magnolia blossoms (Magnolia stellata)

Aside from Townsendias and spring beauty (Claytonia) the bulk of our native wildflowers are smart enough to wait until May, June or even later summer to bloom. Natives know that frost in Colorado can happen late in spring and early in autumn. But plants from Maritime climates have evolved where spring comes and stays. Such is the case with the fabulous spring flowerin g magnolias: these largely come from China and Japan where winter can be harsh, but spring usually arrives for good. Most years we are lucky to have a week of magnolia flowers before a hard frost turns the white or pink petals into brownish orange sludge…two springs ago, and last spring as well we had light frosts for weeks through March and April before summer made a definite arrival. Three springs of magnolia bloom is almost unheard of! Will we keep dodging the frost bullet?

Magnollia stellata
There are two stunning magnolias on the southwest corner of Denver Botanic Gardens’ Waring house. They have been coming into bloom for several weeks, and the white star magnolia is in peak bloom as I type this. I have  used these as “Poster Girls” of how NOT to plant magnolias: do NOT put them on the hot south side of your house (except, that is, for the evergreen sorts–these are summer bloomers that need extra heat to thrive here). Spring blooming magnolias are understory trees that do best on the NORTH Side of your house where their flowering is often delayed several weeks and they are less apt to freeze.  It is also easier to keep their roots cool and moist, since these are emphatically not xeriscape trees…

That said, our star and saucer magnolias bloomed through last year and the year before. And perhaps this year they shall dance their way past yet another volley of frosty bullets to delight and entrance us with their enormous, waxy, fragrant chalices! Get ye hence! And get more of these treasures to brighten up our springs, O Front Rangers! Our springs merit a lot more bulbs and gorgeous trees like this to celebrate the new growing season!