The Finale Begins

October 14th, 2013

   This week is shaping up as peak week for fall foliage in our section of southcentral Pennsylvania – and I’m not just talking about the forests.

The fall show beginning in George’s back yard.

   Lots of landscape trees and shrubs also turn spectacular shades of red, gold, purple and yellow this time of year. Of course, that’s assuming you planted enough fall-peakers to produce a show.

   I really like spring, but fall comes in a close second because so much happens in such a short period of time.

   Unlike spring-blooming plants that spread out the show over 2 or 3 months, fall-foliage plants do their thing over just 2 or 3 weeks.

   Add to that the perennials that bloom in fall, the annuals that are still chugging along in advance of the first killing frost and shrubs that are reblooming, and it all adds up to an action-packed landscape.

   Enjoy it. We’ll be in winter mode before we know it. But if there’s little to enjoy in your yard, get planting or get planning to add more fall interest to your one-dimensional yews, forsythias and dwarf Alberta spruces.

   One of my yard’s fall favorites is the Korean stewartia tree off my back patio. It’s just now turning a blend of deep burgundy, gold and burnt-orange – colors that change day-by-day like a kaleidoscope over about 3 weeks.

Leaves turning on George’s Korean stewartia.

   My favorite fall perennial (at least today) is the threadleaf bluestar (Amsonia hubrichtii), a 3-footer with almost needle-like foliage. I’ve got two of them, and they’ve both turned a bright-gold and russet combination to make a tag-team perfecta of color and texture.

   My dogwoods have been reddish-purple for almost 2 weeks (they’re as early to turn as anything), and the Virginia sweetspires are just starting to show hints of red.

   Don’t forget to look down as well as up.

   Most of my annuals are still showing plenty of color (especially coleus, begonias, petunias and dwarf zinnias), and the perennial sedum, mums, asters and goldenrods are also still flowering.

   Fruit is another big part of fall color. My favorite-fruiting holly is the ‘Red Beauty’ upright I’ve got along the west front border. The fruits are bigger than peas, bright red in color and especially showy on the branch tips of this variety.

   The berries on my winterberry ‘Red Sprite’ are also now red, and my purple beautyberry ‘Early Amethyst’ is loaded with BB-sized, metallic-purple fruits all along its stems.

   Most of my roses are reblooming, and my dwarf butterfly bush ‘Lo and Behold Blue Chip’ never stopped.

   The rain we’ve had in the last 10 days perked up most plants and got our lawns back to green from the brink of brown. That last storm drenched up pretty well and knocked the leaves off a few things, but at least the wind wasn’t bad. That’s what can really short-circuit a fall-foliage show.

   All in all, it’s been a good season leading up to this fall finale.

   Leaf-watchers will tell you that the perfect recipe for the best fall-foliage show is a warm, wet spring, a moderate summer and especially sunny fall days with cool fall nights and fairly dry conditions.

   That’s pretty close to what we’ve had.

   According to the state Department of Conservation and Natural Resources, foliage peaked the first week of October across northern Pennsylvania with a pretty good show from the maples, ash and birch.

   We’re forecast for our peak from now through Oct. 26 – one that’s supposed to be at least average in performance.

   DCNR says the deep, blood-red color of the staghorn sumacs has been especially striking so far this season. I’ve seen a few, too, and I have to say I was impressed at the color on this lance-leafed, tree-of-Heaven look-alike that a lot of people would call a big weed.

   Reds, crimsons and purples can vary a lot from year to year since plants manufacture varying amounts of anthocyanin (the pigment responsible for those colors) based on late-summer and early-fall temperatures and soil-moisture levels.

   The yellow- and gold-producing carotenoids are in leaves throughout the season (just hidden by green chlorophyll), and so they tend to more consistent from year to year.

   You know why the trees and shrubs are doing this, right?

   No, it’s not because they want to give us a nice sendoff since we’re about to suffer through another dark winter.

   Leaf-dropping plants have to get rid of their leaves as a way to reduce moisture loss over winter when the ground is frozen and the roots can’t provide water to keep all of those leaves alive.

   Also, chlorophyll production goes downhill with shortening days.

   The bottom line is that leaves become a liability instead of a life-giver in fall, and a tree is “smart” enough to dispose of them according to each season’s cues.

   The change in color is a step in that shedding process, and it’s one we like to see last as long as possible.

   The other way that can happen is when a sudden freeze or a sudden wind storm comes along and knocks the leaves off while they’re still mostly green.

   So far, so good on that this year…