Nature’s Paintbrush At Work
This year’s autumn equinox (Saturday, September 23) is almost here, marking summer’s exit and fall’s entrance. Since every part of the globe experiences some form of seasonal shift, solstices and equinoxes are celebrated everywhere in various ways. Pretty much all of these celebrations feature special food as well as (surprise!) intoxicating beverages. In the Northern hemisphere, where autumn ushers in the dimmer, shorter days of winter, traditional festivals often focus on light in the coming darkness. One of my favorites is the Chinese Moon Festival, featuring lovely, round, paper lanterns to light and delectable round moon cakes stuffed with chopped nuts to share with family and friends. A nearby neighbor’s balcony is illuminated with large round lanterns that glow like many moons in soft pastel shades through the dark nights. Now I’m inspired to hang some smaller globes in my own little covered porch as a gentle way to light up the night and spark a little happiness.
Last week marked farewell to light-filled evenings here-the Seattle area won’t see twilight after 8:00 pm again until mid March. Morning light is shrinking as well, prompting plants to begin to shut down for winter slumber. After a very dry summer such as we had here, it’s wise to continue at least minimal watering of new plants and transplants well into winter, as in some places deeper soil never got saturated at all last year. It’s also important if you want your garden to be as bold in autumn as it is in summer. Moderately moist soil makes for more vivid and longer lasting foliage color displays in the garden as well as in the woods and fields. Though rain is still scanty and rare here, the heavy autumn dews help to boost plant health as well as fall color.
Soil moisture affects both the timing and potency of leaf color; warm and wet summers followed by warm, sunny fall days and cooler nights make for the most dramatic displays. Cold, late springs and hot, dry summers can delay or diminish fall color as will autumn heat, which encourages rapid leaf fall before potent colors can develop. In such a disappointing year, leaves turn brown and drop without their time of glory. This year, local trees and shrubs have been showing a little color for a few weeks, and as the nights grow cooler, the colors are intensifying beautifully.
In gardens, compost mulch can boost blazing color in everything from maples and ginkgos to spireas and hydrangeas to Blue Stars (amsonia) and peonies. That’s because compost helps plants build up brix, natural sugars that contribute reds, coppers, oranges, golds and purples to the foliage fiesta. Though the loss of chlorophyll stored away summery sugars, cooler autumn nights shrink leaf veins so newly produced sugars can’t escape to the twigs. Instead, they become brilliant colors; anthocyanins (which put the blue in blueberries) create reds, purples, and burgundy, while carotenoids (which make carrots orange) create yellow, gold and orange tints. Beneficial bionutrients for all!
A Legacy of Lovely Leaves
Wherever they flourish, deciduous trees (especially hardwoods like beech, maples, and oaks) can be almost shockingly beautiful in a good leaf color year. While soil nutrients and moisture are important keys to color, briefer days trigger the reduction in chlorophyll production that allows the hidden sugars and minerals to shine. As photosynthesis slows down with the dwindling daylight, leaves loose their greenness, changing the chlorophyll into nutrient compounds that get stored in twigs for the winter, ready to feed baby buds as winter wanes.
When the leaves fall off, you can often see the tiny nubs that are next year’s leaves in the making. The leaves themselves are also packed with nutrients that help feed the soil which in turn feeds the tree roots. This beautiful cycle continues unbroken unless somebody gets into a fit of tidiness and removes the leaves. If the look of loose fallen leaves is too messy for anyone, the simple ecologically sound solution is to shred those leaves and put them right back where they belong. Just saying…
There’s An App For That (Of Course There Is)
If you’re seeking a great place to enjoy fabulous fall color, there is now an app for tracking the progress of leaf changing color peaks across the country (see below). Slide the bar below the map image to track projected color changes by date and region. The map is updated often to help promote tourism for rural areas where leaf lookers can boost local economies that often drop after summer vacationers leave. Onward, right?