Printer Friendly

Watch out, New England! The West has its share of spectacular fall color. Here are colorful trees for your own garden.

Watch out, New England! Framed against deep blue autumn skies, brightly colored fall foliage can stage a spectacular show in many parts of the West. The fiery reds, radiant oranges, and vibrant yellows of Chinese pistache, ginkgo, liquidambar, and other choice deciduous trees can transform a garden, street, or neighborhood into a blaze of color.

Although large trees provide the most dramatic display, you don't have to wait years to enjoy brilliant fall color. Even young trees create a handsome effect in the landscape.

Depending on weather conditions and the type of tree you plant, the length and intensity of fall displays can vary from year to year. But in mild climates where killing frosts and cold rains come late--if at all--many types of trees hold their color over a long period of time. In Southern California, it's not unusual to find trees changing color from September to January.

The varieties listed in the chart on page 90 grow in a wide range of climates; most change color fairly consistently even where winters are mild. In Southern California, trees that require cooler temperatures to trigger color change (Japanese maple, Raywood ash, and scarlet oak) develop more intense colors in canyons and inland areas.

What makes leaves turn color?

Changing color is part of a leaf's normal aging process. When the leaf stops making food (chlorophyll), its green color disappears. At this stage, genetics determines the intensity and hue of the leaf's color. Some leaves may never turn bright colors, regardless of external conditions, if color change isn't in the genetic make-up of the parent tree.

As the chlorophyll disappears, different pigments, previously masked by green, begin to show. Carotenoid pigments turn leaves bright yellow, as in gingko and tulip trees. In liquidambar, Japanese maple, and other trees that develop bright red to purplish foliage, anthocyanin pigments take over. Leaves often show combinations of pigments, too.

In seed-propagated species, genetics varies from tree to tree, and color differences among the trees may occur. That's why some individual trees may be more spectacular--or less so--than others.

For example, one seed-grown maple may turn a glowing orange, while another, grown under the same conditions, may be a disappointing brown. This holds true for seed-grown Chinese pistache, Chinese tallow tree, Japanese maple, red and scarlet oak, and sour gum.

Hybrid trees propagated by cuttings, grafting, and other asexual methods always inherit the potential colorful characteristics of the parent. Examples include 'Aristocrat' ornamental pear and 'Burgundy' liquidambar.

Weather can make or break a show

Even if you select a tree known for its fall color, the display each year depends on weather and cultural conditions. Yellow color develops as days shorten, as long as there are no killing frosts (which destroy leaves) or strong winds. Red and purple pigments show up best when warm, sunny days are followed by cool nights.

If nighttime temperatures stay warm through fall, leaves may turn yellow, but reds, purples, and oranges may be muted. This means that red-hued trees, such as Japanese maple, tend not to color up as consistently in mild coastal climates where the difference between day and night temperatures is less than in inland and northern climates.

Day length can also influence when some trees change color, with shorter days and longer nights triggering the leaves to turn. You can see the impact of day length when a liquidambar grows next to a street light. If the street light uses sodium vapor (most do), the tree reads it as long spells of daylight, and leaves on the tree's lit side may never change color in the fall.

Other factors may mute or prevent fall color displays. Severe drought, disease, and an early killing frost may wither foliage prematurely. Strong winds can blow off leaves before colors peak. Wet soil, often found in lawns, can delay color development in many trees, such as Japanese maple and liquidambar; mild drought stress, however, often enhances color development.

Choosing and planting a tree

Using the list at left, select a tree that's both adapted to your climate and known for its colorful display. Climate zones in the Sunset Western Garden Book indicate the best growing regions for each. Your nursery may have additional suggestions for trees that color up well in your area. Make sure you have space in your garden--some types grow quite large (our chart lists likely mature height).

If you choose an asexually propagated hybrid such as Raywood ash or 'Festival' liquidambar, you can depend on it to develop good fall color no matter which tree you choose in the nursery, as long as the tree is given the right cultural conditions and the weather cooperates.

With seed-propagated types, choose a tree while it's in color. Depending on the year and conditions, a tree may or may not show its true color in the nursery (water supply and weather affect performance). But if you do find one with colorful leaves, you know it has the potential to put on a good show in future years.

To catch a particular variety in color, call the nursery before you visit and ask if leaves have begun to change.

For best displays, plant trees where they get full sun most of the day--at least from noon on. Trees in part or full shade won't develop intense color. Choose a site with well-drained soil and keep it on the dry side in the fall.
COPYRIGHT 1989 Sunset Publishing Corp.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1989 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Date:Nov 1, 1989
Previous Article:The Presidio. Another great park for San Francisco?
Next Article:Very nutty tarts.

Related Articles
Favorite fall-color drives.
Colorful climbs: several eastern national offer the best vantage points to view fall foliage.
Making The Most Out Of The Fall Foliage Season.
Fall color acts as sunscreen. (Update).
New England autumns unsurpassed.

Terms of use | Copyright © 2016 Farlex, Inc. | Feedback | For webmasters