In the woods of the Pacific Northwest, Ceanothus shrubs are pretty common and unassuming members of the understory, squatting resentfully beneath glamorous firs — like federal employees toiling at their desks below the shiny flagpoles of their elected bosses.
Ceanothus does grunt work, fixing nitrogen at an impressive rate. Then, one day, it gets its chance, its big break: a forest fire that wipes out most of those trees. Ceanothus burns, but it regenerates fast from roots and grows thick and tall, making those once-lovely forest stands thick and impassable with 10-foot-high tangles of evergreen leaves. They become the landscape for a while before the trees get the upper hand again.
Or at least that’s how I’ve seen it happen, in one burned area where natural regeneration was allowed to proceed.
Now in the garden, cultured varieties like ‘Victoria’ are popular, because of the spectacular purple flowers. But Ceanothus’ wild properties are still lurking there. A small bush can turn into a huge impenetrable green blob fast — which for several weeks each year will turn into a huge purple blob, especially impenetrable because it is serving as a kind of Burning Man for bees.