Southern Magnolias in a Northern Town

As our urban forest disrobes and a steely-gray nuclear winter sky descends over Boise, I'm reminded again of how much I appreciate the glossy, evergreen foliage of the Southern Magnolia (Magnolia grandilflora).

Here are some interesting tidbits about the Southern Magnolia in our climate:

  • There is a wide degree of variability amongst the many available cultivars, with Edith Bogue, Victoria and Bracken's Brown Beauty consistently overwintering well in our SW Boise Zone 6 property (there are reports that Edith Bogue even grows in Chicago).
  • Winter desiccation from dry, cold wind is really tough on these broadleaf evergreens. If you live in a very windy, exposed site or south of Lake Hazel, forgetaboutit.
  • In our climate, Southern Magnolias drop their three year old leaves in the spring and early summer (much to the consternation of those unfamiliar with this cycle!).
  • Our Southern Magnolias need no more water than an average hardwood tree and have happily grown without fertilizer of any kind in our nasty, caliche "soil".
  • Fragrant blossoms begin to appear late spring and continue into mid-summer.

Here's a picture tour of Southern Magnolias around Boise:

Ruby red seeds of summer's spent flowers juxtaposed against  lush evergreen foliage.

Lake Heron planting in 2003.

Ten years later! Yes, a bit close to the foundation,  but in my defense we had just visited Georgetown where Magnolias planted within a few inches of brick walls are de rigueur
Another 2003 planting....

Same tree, today (again, in the Georgetown style).

Edith Bogue in our garden
The closely related Magnolia virginiana. Flowers have an intense citrus aroma. 
A new, apparently hardy cultivar that my friend Steven Gossett grew from a seed he harvested from Spain. He calls it Granada.
Another cultivar in Steven's nursery, -24. Fortunately, we haven't had the recent opportunity to see if it lives up to the name!

The last two are significant because they both survived -20F -22F back in the early 90's December 22nd of 1991. So those of you who think we live in Zone 5, take note (you know who you are).

Foothills East

The largest Southern Magnolia I've found in Boise is near Winstead Park. The oak behind it adds some nice contrast. The owners have told me that after -20 F -22F, the tree completely defoliated but stubbornly pushed out new leaves in the spring.

Same tree, different angle