Fall has a way of sneaking up on our Central Coast gardens. It doesn’t arrive in one fell swoop like so many places. There’s not a single cold snap or deep freeze to announce that the seasons have changed.
Instead, we get a mish-mash of conditions for a month or two, with temperatures bouncing around from the 40s and 50s at night to the low 60s to the low 80s during the day.
But the trend is still toward shorter days and crisper nights. And then suddenly — indeed, sometimes it seems overnight — our deciduous trees erupt into glorious fall color.
Granted, you’re not likely to see the postcard-perfect images that you’ll find in New England, where vast stands display impossible shades of brilliance.
Much of that is because we have a greater diversity of trees, with many different tropicals, subtropicals and evergreens mixed in with our deciduous trees.
We also have a slower progression of color. Rather than busting loose all at once, followed by a quick fade, our leaves typically take their sweet time to shift color, then drop.
As a result, we may see the first hints of color in September, with Japanese maples starting to turn, followed by persimmons and maidenhair trees. Others, such as birches and sycamores, often come late to the party, not fully coloring up until November or even early December.
But ultimately, it doesn’t matter how fast our trees turn, or whether they’re planted in masses or as single specimens. They’re all beautiful this time of year, especially at sunup and sundown, with the low rays of sunlight shimmering through their tissue-thin leaves of red, yellow, purple and orange.
The following are among the best.
American sweet gum (Liquidambar styraciflua)
This robust tree bears maple-shaped leaves that turn gold, red and burgundy in fall. It has a nice, upright shape, and grows moderately fast to 60 feet tall and 20 to 25 feet wide. Although American sweet gum is a popular street tree in older neighborhoods, its beefy surface roots can lift pavement. So plant yours at least 10 to 15 feet away from sidewalks, patios, driveways and the foundation of your home. That will also help you to avoid having to constantly sweep the golfball-sized sticker balls that drop much of the year.
But all is forgiven when those leaves turn color and light up the neighborhood.
California sycamore (Platanus racemosa)
This statuesque native produces giant, leathery, maple-like leave that turn the richest orangey-gold in the coldest spots on the Central Coast.
Just south of Buellton, California sycamores that line the stream corridor along the east side of Highway 101 yield brilliant hues every year.
In milder areas, you’ll generally see a mix of rustic brown and gold, and even a few pale green leaves that never really turn.
After the leaves drop, the solid trunks reveal zig-zagging branches and beautiful, mottled, peeling bark in shades of white, tan, cinnamon and dark brown.
California sycamore grows fast to 80 feet tall and 50 feet wide. It is not for the faint of heart — or for small gardens.
Chinese pistache (Pistacia chinensis)
If you plant only one tree for fall color, let it be Chinese pistache.
Neat and well-mannered, with roots that stay within bounds, it nonetheless trumpets its presence in fall as a raucous fireball of orange and red. On close inspection, some leaves turn yellow and pink as well. Adding to the explosive effect are dangling leaflets that dance in the breeze.
Chinese pistache grows 30 to 60 feet tall and wide. A relative newcomer to many neighborhoods, it will be interesting to watch as the various trees take on size over the next 10 to 15 years. As with many trees, it performs best with good drainage and deep, infrequent watering.
European white birch (Betula pendula)
This traditional front yard tree grows narrow and tall, and is often planted in groups.
The arrowhead-shaped leaves, hanging from weeping branches, turn to liquid gold in the fall.
Those leaves offer a beautiful, stark contrast to the white and black furrowed bark.
Mature trees reach 40 feet tall, 20 feet wide and form a surprisingly broad trunk a foot wide or wider.
If you plant several, vary their initial sizes so that they don’t grow into three equally stout trees in 15 to 20 years.
Also know that greedy surface roots will crowd out any underplantings, including lawn, over time.
I’m planning to replace a swath of declining fairy fan flower (Scaevola ‘Mauve Clusters’) beneath my European white birch with an underlayment of landscape fabric topped by dark, polished pebbles, come spring.
Japanese maple (Acer palmatum)
This dainty tree produces some of the earliest and most spectacular fall color, although its delicate leaves drop relatively fast. It grows to about 20 feet tall and wide, depending on the variety.
More than a dozen Japanese maples are commonly available, ranging from Bloodgood, which bears scarlet leaves in fall, to coral bark maple, which turns an ethereal yellow.
Protect your Japanese maple from the harshest elements. It will be at its best tucked into a sheltered corner or beneath a taller, evergreen tree, where wind and heat won’t tatter its leaves and turn them crispy.
Japanese or oriental persimmon (Diospyros kaki)
Often overlooked until it sports fall color, this fruit tree bears round, nearly heart-shaped leaves that shift from green to yellow to deep, glowing orange. Plump, orange fruits that hang on long after the leaves have dropped are a bonus.
As a shade tree, persimmon has a nice, rounded silhouette and grows 30 feet tall and wide. As a fruit tree, it’s generally grafted to yield Fuyu, a nonastringent fruit that’s sweet when picked; or Hachiya, an astringent fruit that softens and sweetens after picking.
Maidenhair tree (Gingko biloba)
Year in and year out, this showstopper yields what may be the most vibrant yellow of any Central Coast tree.
It’s also among the most reliable for turning color, even with the mildest of temperatures.
The drooping, fan-shaped leaves then fall nearly all at once, gifting the earth with a golden glow.
Maidenhair tree is one of the oldest flowering plants on earth, dating back some 200 million years. Male trees bear small, inconspicuous flowers, while females produce large, fleshy seeds in late fall that smell positively hideous. Fortunately, nurseries seldom offer female trees for sale.
Maidenhair tree often starts out slow, then speeds up, eventually reaching up to 50 tall and about half as wide.
Purple-leaf plum (Prunus cerasifera)
The already dark leaves of this fruitless plum turn nearly inky black in fall.
It is especially beautiful when offset by the golden tones of a European white birch or brilliant yellow gingko.
Purple-leaf plum sheds its leaves from the top down, so can look a little awkward just before the last leaves drop.
This tough tree withstands wind, poor soil and street pollution, and is found in neighborhoods everywhere. It generally grows upright, to 30 feet tall.
A dozen or so named varieties, such as Krauter Vesuvius and Purple Pony, may have slightly different forms, and be more rounded or not quite as tall.
Why Leaves Change Color
Fall color is the result of deciduous plants preparing for winter.
Before dropping their leaves, the plants convert the starch in their foliage to sugars to store in their branches, stems and trunks to sustain themselves until they leaf out the following spring.
But cold temperatures can hinder the process, preventing the sugars from reaching their destinations. That buildup of sugars often appears as red pigment.
Meanwhile, the green chlorophyll in the leaves breaks down, revealing any other pigments that might have been masked, such as red, yellow, purple or orange.
The mashup of stalled sugars and pigments results in what we see as fall color.
Colder temperatures often heighten the hues, while mild temperatures can dull them. Strong, afternoon sun can intensify colors as well, sometimes to the point that the southwest side of a tree may sport more vivid color than its other sides.
Seeds of Wisdom
Fall color is not limited to trees. Deciduous shrubs, grape vines and some fruit trees, including peaches, plums and pluots, can produce dazzling foliage as well.
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