Lack of flowers doesn't translate into lack of color
There is no reason to lament the lack of color in Southern California gardens at this time of year. Even without flowers, a kaleidoscope of colors is available to us due to a large variety of trees, shrubs and vines whose foliage, bark and berries offer a rainbow of botanical pigmentation.
Let's start with European white birch (Betula pendula). Leaves turn golden yellow before dropping off to reveal multiple, brilliant white trunks. Lombardy poplar (Populus nigra variety Italica) has similarly colored foliage and a strong columnar growth habit that makes it an appropriate choice for a colonnade of trees on either side of a long entryway, as a windbreak, or as a boundary tree along property lines. Weeping willow (Salix babylonica) is a poplar relative whose beauty is unsurpassed, with foliage that turns a pleasant golden color, even if it lives no more than a decade in our area. If anyone has grown or knows of a local weeping willow older than this, please write to me about it at the email address below.
The most brilliant foliar gold is found on Arizona ash (Fraxinus velutina), which grows quickly to a height of 30 feet. The Modesto variety was once highly sought due to its vigor, but susceptibility to fungal diseases has damaged its reputation over the years. Sticking with gold, you may want to plant a ginkgo tree (Ginkgo biloba), whose bi-lobed, fanshaped leaves are an aesthetic bonus. Finally, our native black walnut (Juglans californica) must be on the list of trees with glittering gold autumn foliage.
Several trees showing off orange, red and burgundy colors, in addition to gold, are notable. Leading this group is Chinese tallow tree (Sapium sebiferum). Its leaves have a glow I have never seen on any other plant. You must acquire one if you are in the mood for an unparalleled foliar light show during the holiday season.
The widely planted crape myrtle (Lagerstroemia indica) is also resplendent in the gold-to-burgundy foliar spectrum, to say nothing of its exfoliating bark in cream to cinnamon, depending on the variety. The even more brilliantly orange and red-leafed Chinese pistache (Pistacia chinensis) forms a handsome dome at a height of 30 feet.
This classic fall foliar color palette is repeated in the sweet gum (Liquidambar styraciflua). The problems with the strong, vertically growing sweet gum are its aggressive roots and spiked, spherical seed capsules.
You can eliminate the seed capsule problem, at least, by planting the rotundifolia sweet gum, a virtually capsule-free species whose leaves turn to a solid burgundy each autumn. Bradford pear (Pyrus calleryana variety Bradford) has the most brilliant burgundy fall foliage of any tree, but keep in mind that its clusters of branches grow out from a single point, and their breakage is a constant concern. When it comes to fall color, the Chinese flame tree (Koelreuteria bipinnata) is noteworthy for its unusual, papery seed capsules that turn magenta at this time of year. Its large panicles of golden flowers bloom in the spring with a mild fragrance. You can see it growing in Sherman Oaks on Ventura Boulevard just east of Hazeltine Avenue.
When it comes to a color change in the foliage of shrubs, three species in the barberry family take center stage. Let's start with the Oregon grape (Mahonia aquifolium). Its name is misleading since its habitat stretches from British Columbia to Northern California. Its leaves have spiny margins that give them a resemblance to holly. Flowers are yellow and followed by purple fruit, while leaves turn orange and red in fall and winter. Heavenly bamboo (Nandina domestica) turns color in the fall; its compact and dwarf varieties such as Gulf Stream are most colorful of all. Japanese barberry (Berberis thunbergii) assumes a fiery aspect in the fall, while the atropurpurea variety has bronze to reddish-purple foliage year round, and Rose Glow shows off foliage that is a melange of red, pink and white.
As to vines with fall color, Roger's Red is of special interest, as it is a hybrid between the native California grape (Vitis californica) and the European wine grape (Vitis vinifera). Its vivid scarlet color this time of year makes it a suitable candidate for covering an arbor or growing up a trellis. I want to thank Robert Ginn, a master gardener who worked many years at the Hollywood Bowl, for reminding me of the spectacular hues displayed by Boston ivy (Parthenocissus tricuspidata). Its full spectrum of fall colors is highlighted when grown up a gray block wall, climbing easily without any artificial support.
Porcelain berry (Ampelopsis brevipendiculata) is probably the most decorative vine you could hope to grow on account of its berries, which appear in a color range that includes lilac, light blue, dark blue and purple. It is an ideal candidate for growing up a chain link fence due to its tendrils. Leaves are similar to those on grapevines, and the Elegans variety has pink and white variegation to go with the multicolored berries for an added ornamental touch. You can procure this vine at Etsy.com.
Persimmon trees are also recommended for colorful fall foliage as well as for their decorative orange fruit, which ripens in November.
If there are any trees, shrubs, vines or ground covers you recommend for fall color, let me know about them at joshua@ perfectplants.com. As always, you are invited to send questions and comments regarding any gardening practice or problem.