Leaves that linger
Wacky weather ride could have triggered something called marcescence
This week the rain arrived.
It washed the snow away and revealed mushy leaves — leftovers from October. Leaves on lawns and in gutters. Not to be confused with the leaves still on the trees.
They’re weird, aren’t they? Some trees reliably hold their leaves through the winter, such as beech and oak. But this year, many are still rattling crispy leaves. The Japanese maple in our front yard remains 50 per cent covered with leaves that should have fallen in October.
Is it climate change? Is it a response to our erratic fall weather? In late October we hit a high of 26 C and in November a high of 16 C but five days late the temperature dipped to -5 C. That wacky ride could have triggered something called marcescence — that’s when some trees retain withered leaves long after others have fallen. The cold snap after the heat may have interrupted a natural process where enzymes form to “unglue” dead leaves from the tree.
When the weather turns freaky it’s human nature to think such a thing has never happened. People are astounded when crocuses
start to grow in January or lilacs bloom in November. It’s happened before and it will happen again. Some disturbances will be tagged to climate change, others to the reliable pattern of unreliable weather.
Gardeners and farmers are early responders, of a sort, to weather oddities. I know I have proof of such things in my clipping files. In a recent flurry of purging and reorganizing my office, I hauled out garden columns from 2007. Ten years ago, I wrote about the shock and thaw of January 2007. On New Year’s Day anemones were in bloom and the hellebores were on the cusp of flowering. But we were all worried that a sudden deep freeze would damage the tissue and flower buds of plants.
A year later warm and cold spells in January prompted a column on the wind machines used in the Niagara vineyards to mitigate prolonged cold spells. (Ironically, that same folder had a story about Torontonians moving to Hamilton because of bargain house prices. Sound familiar? For $270,000 you could buy a 3,000-square-foot house on St. Clair Avenue. But I digress.)
Cycles are hard to ignore in gardening and January kick-starts the season. There’s not much else to be done this month other than watch the weather. It’s a little early to cut branches for forcing, and the idea of starting and nurturing seeds (if you don’t have a proper setup) seems premature. In the past I’ve extolled the pleasure of raking in January; now I would change that to sweeping, with one of those handy palm leaf brooms. The bristles won’t damage plants and the broom is good for chasing litter and debris out of ground cover.
One thing I won’t do is try to pluck any leaves off the Japanese maple. Experts suggest this could lead to moisture loss if the not-quite-sealed openings between leaf and branch are exposed.
So what to do during the hands off days of January? I like the sound of the Winterblooms exhibition (www.winterblooms.ca) in Dundas starting Jan. 26. At the Dundas Valley School of Art, the Carnegie Gallery and the Dundas Museum and Archives there will be florists and artists collaborating to celebrate flowers and art.
Now that’s something to take your mind of those lingering leaves.