Family: Cannaceae (Canna
the “official” plant for the month of May. But
this year, let’s think larger and bolder. Much larger
and much bolder.
I’ve been bitten by the summer-bulb
bug, for reasons that aren’t entirely clear, even to
me. Perhaps it’s because I want to explore yet another
new aspect of gardening. But it’s also a practical way
to deal with some bare spots in the garden—particularly
in places where I haven’t yet hit on the specific plant
I want to install as a permanent resident. Bulbs are easy and
quick to put in and practically grow themselves—and here,
I’m using the catchall term “bulb” to include
rhizomes, corms, tubers, and tuberous roots. So for summer
color I can choose from begonias, lilies, and gladiolus—and
dahlias, of course. I leave the growing of the latter to Dick
Porter. For years I’ve also eschewed lilies and glads.
And cannas I wouldn’t even consider. But this year, inexplicably,
I’m fascinated with them all—especially canna lilies.
Maybe it’s all the times I’ve admired them in Peace
Arch Park while waiting in line to cross the border. Or it
might be distant memories of old gardens I knew as a child.
Didn’t all our grandmothers grow “common” red
At last count, the genus Canna—the
only one in the Cannaceae family—included 55 species
indigenous to the tropics and now naturalized around the world. Canna
edulis is native to South America, where its fleshy rhizomes
are a food source. They’re dried and pulverized into
what’s called tous les mois in France and “arrowroot
flour” in Britain—although the arrowroot we use
here in cooking as a thickener comes from Maranta arundinacea,
another plant entirely. The seeds of several canna species
are used to make jewelry, because they’re very hard and
uniformly shaped. It’s rumored they served as a substitute
for lead shot in flintlock muskets during the 18th and 19th
The canna lily is a perennial grown from a rhizome,
just like the lily-of-the valley. The two plants are otherwise
unrelated, although the large leaves of the canna do resemble
the tiny leaves of the lily-of-the-valley, in form if not in
color or size. Linnaeus categorized Canna indica—and
he didn’t use leaves so much as the reproductive parts
of flowers to organize his classifications. The Canna flower
has one stamen and one pistil, which placed it in the Monandria
class and the Monogynia order. The word “canna” is
from the Latin for “cane” or “reed,” and
Linnaeus named that first species he saw after what he thought
was its country of origin—India.
What our grandmothers grew might have been Canna
indica. It’s actually a New World native and grows
in the wild throughout the Caribbean and Pacific islands,
where it’s on the verge of being declared a nuisance.
It’s unlikely to take hold to that degree in our area.
An enormous number of named varieties are now available for
our home gardens, and show-stopping they can be. Choose yours
carefully. There are cannas with small flowers and others
with very large flowers, in a range of brilliant colors.
The foliage varies from variety to variety and is frequently
as extraordinary as the flowers. You may actually have to
depend on the foliage for effect rather than on the flowers,
because cannas bloom late in what they hope will be a hot
summer. They may be slow to blossom here, in any given year,
and may not come into their own until the weather is too
cool to sustain them. Where they do get a great deal of heat,
some varieties can top out at almost fifteen feet, but you’re
unlikely to see that here in our cool-summer climate. Those
that are full-size may make it to five feet. If even that’s
too much height for the space you have available, select
one of the many dwarf varieties. You’ll get the same
great flowers and almost as many outstanding foliage choices,
but on plants that are only two or three feet high.
your canna rhizomes before the middle of May in the richest,
most moisture-retentive soil you can
manage, where they’ll get full sun. Place them about
four inches deep and eighteen inches apart—eyes up if
you can find them, but don’t worry if you can’t.
Just lay the rhizomes in the ground horizontally. Cannas are
heavy feeders, so add some fertilizer according to package
directions when you plant and at monthly intervals during the
summer. Use a complete, balanced formulation or—better—one
that goes easy on the nitrogen. Avoid feeding cannas excess
amounts of this particular nutrient, so make sure that first
number is not greater than the other two. All cannas need at
least some moisture administered regularly. Read up on your
varieties to learn their specific requirements. Some are actually
bog plants and will thrive along the shallow edges of ponds.
Others are marginal, and appreciate wet feet. Many will do
fine with a weekly deep soak.
for slugs when the shoots emerge, and keep checking through
the growing season. We know our abundant
slug population has quite a taste for things succulent and
tropical! Then stand back. When late summer rolls around, you’ll
appreciate the “bold” move you took in May.