Maidenhair Tree

Maidenhair tree leaves look rather ‘fishy’.

There are not many trees that are as reliable for strikingly bright and clear yellow autumn foliar color as the maidenhair tree, Gingko biloba, is, even in mild coastal climates. The distinctive leaves flare out like fish tails, each with a prominent cleft that divides it into two wide lobes. (The species name ‘biloba’ means ‘two lobed’.) Some cultivars lack foliar clefts, have narrower leaves, or even develop milder yellow color in autumn. Those developed for home gardens exhibit relatively symmetrical branch structure, and are exclusively male, so can not produce the stinky fruit that some older female trees drop. (Trees grown from seed can be either male or female. Female cultivars are grown for fruit production and bonsai.) Some ancient trees in Japan, Korea and China are more than a hundred feet tall. Fortunately, maidenhair tree grows slowly enough to stay proportionate to compact urban gardens for many decades.

Maidenhair trees develop the best yellow fall color.

Chinese Pistache

Chinese pistache colors with minimal chill.

Those who crave fall color in mild climates should appreciate Chinese pistache, Pistacia chinensis. It is happy to provide fiery yellow, orange and red color in response to a slight chill. Actually, it retains its colorful foliage later into the season with mild chill than it does with frosty weather. Rain eventually dislodges all of its deciduous foliage through winter.

Because it is so resilient to harsh situations, Chinese pistache is popular as a street tree. Pruning is necessary to establish adequate clearance of broad limbs over roadways and sidewalks. Since roots can be shallow with regular watering, root barriers should protect nearby pavement. However, established trees do not need regular watering, if any at all.

Old Chinese pistache trees, as well as those that grow wild from seed, are either male or female. Female trees produce tiny but annoyingly abundant fruit. Modern cultivars are all male, and therefore fruitless. They may get more than forty feet tall, with broad canopies. The pinnately compound leaves are just about eight inches long.

Fall Color To Fall For

Fall color develops with seasonal changes.

Autumn is also fall here. Actually, ‘fall’ is the more popular name. It had been the popular name in England during the Sixteenth Century. The (generally) French name of ‘autumn’ became more common there during the Seventeenth Century. Yet, both names remained in use in the American Colonies. That is why autumn foliar color is more simply fall color. 

The natural fall color in New England, the Appalachian Mountains, the Rocky Mountains and the Great North Woods is famously exquisite. So many of the native deciduous trees develop remarkable fall color in response to local weather conditions. These same trees might not get sufficient chill to develop comparable fall color in milder climates of Florida. 

In most regions of California, natural fall color is limited by the ability of native species to develop such color. Bigleaf maple and the various poplars turn bright yellow with a slight chill, but are not abundant. Even when chilled, the foliage of most other native deciduous trees simply shrivels and falls without much color. Most of the native trees are evergreen. 

Therefore, most of the best local fall color is provided by exotic (nonnative) tree species. Such trees not only develop remarkable fall color, but do so in response to minimal chill. Sweetgum, flowering pear, Chinese pistache and ginkgo are four trees that most reliably develop brilliant fall color where winter weather is mild. None are native. All are popular.

Ginkgo turns brilliant yellow. The other three display various colors that range from bright yellow, to fiery orange, to rich red and burgundy. Their colorful foliage lingers longer than that of other deciduous trees. Sweetgum and flowering pear might retain fall color until it succumbs to rain in winter. Of course, these are not the only options for reliable fall color. 

No tree is perfect. Although very colorful in autumn, sweetgum is notoriously structurally deficient, and produces obnoxiously spiked fruiting structures. Flowering pear is innately susceptible to fire blight. All deciduous trees drop leaves, which need raking. Trees must conform to their situational limitations, as well as their particular landscape applications.

Boston Ivy

Boston ivy gets colorful before autumn.

It is the ‘ivy’ of ivy league schools. Nonetheless, Boston ivy, Parthenocissus tricuspidata, is neither an ivy, nor indigenous to Boston. It is from eastern Asia, and is related to grape vines. It is related to Virginia creeper too, which is actually native to Boston, Virginia and the eastern half of North America. It has become popular locally for freeway sound walls. 

Boston ivy is an aggressive clinging vine that can climb to the top of a ten story building. Unfortunately, there are a few problems with that. It ruins wooden or painted surfaces, so can only climb concrete or masonry. It climbs over windows if it gets the chance. Thicket growth is difficult to remove if it is too high to reach. On rare occasion, mice can nest in it. 

Otherwise, Boston ivy works well on freeways. Although deciduous, its vines discourage graffiti. Even while bare, its texture helps to muffle sound. Its exquisite autumn foliar color might begin to develop as early as late summer, and lingers until frost. Boston ivy is quite resilient to neglect. Shabby plants generate fresh new growth after major winter pruning.

Flowering Dogwood

Bloom like this waits for spring.

Flowering dogwood, Cornus florida has something in common with Poinsettia. The most colorful component of their bloom is not floral, but is instead foliar. What appears to be petals are colorful leaves known as bracts. Exactly four bracts surround each small cluster of tiny and unimpressive pale green real flowers. These bracts are most popularly white, but can be pink or rarely brick red.

The deciduous trees are bare now, but bloom spectacularly in early spring. Any necessary pruning should happen after bloom, and preferable after new foliage matures somewhat. Floral buds for next year are already prominent on the tips of bare twigs. Dormant pruning would eliminate some of the buds prior to bloom. For now, only minor grooming of unbudded interior growth is practical.

Mature flowering dogwood trees can be twenty feet tall, but typically stay lower. As understory trees, they prefer a bit of shelter from larger trees. Foliage can scorch if too exposed. Some cultivars have variegated foliage. All can develop vibrant orange and red foliar color for autumn, even with minimal chill. Floral debris resembles fallen leaves that fall just as new and real foliage develops.

Chrysanthemum

Chrysanthemums are just right for autumn.

Mild autumns and arid summers keep chrysanthemums on a different schedule here than in most other regions. They can get planted in spring to grow through summer and bloom through autumn; but because they can take a bit of work, they are more often planted while blooming in autumn. Although commonly grown as autumn annuals, they are perennials that can regenerate next spring, grow through summer, and bloom even better the following autumn.

Centuries of development in Japan have produced more varieties of chrysanthemums than can be documented. There are really some weird types grown for cut flowers or by hobbyists. Garden varieties are mostly limited to simpler flowers that do not need much thinning or staking. Color ranges through all sorts of hues and shades of yellow, orange, red, pink and bronze, as well as a few purplish colors, cream and white. Many have yellow centers. The aromatic foliage is alluring to some, but objectionable to others.

Autumn Color From Deciduous Foliage

Deciduous foliage can get delightfully colorful.

Autumn does not get cool enough locally to prevent everything from blooming. A few plants can bloom sporadically all year except only during the coolest part of winter. A few plants naturally bloom in autumn. Cool season annuals begin blooming before warm season annuals finish. Flowers can potentially provide plenty of autumn color if necessary. A mild climate can be a major advantage.

It can also be a disadvantage. Minimal chill causes deciduous foliage to start to get messy before it starts to get colorful. Some deciduous plants shed completely before getting chilled enough to develop appealing autumn color. A few others do not even get cool enough to defoliate completely. They instead retain their shabby old foliage through winter until new foliage replaces it in spring.

Nonetheless, several adaptable deciduous plants get sufficient chill to develop impressive autumn color here.

Sweetgum, Chinese pistache, flowering pear and ginkgo are likely the four best deciduous trees for autumn color locally. Sweetgum and Chinese pistache produce the most impressive ranges of vibrant colors. Flowering pear is comparable, but with less yellow, and more rich deep burgundy red. Ginkgo lacks such range of color, but develops the brightest and clearest yellow autumn color.

Boston ivy, crape myrtle and persimmon get about as colorful as sweetgum, even if incidentally to their primary duties. Crape myrtle is popular for its abundant and richly colorful bloom in summer. Persimmon is a fruit tree. Boston ivy obscures graffiti and helps muffle sound on freeway soundwalls. Cottonwood and black walnut turn bright yellow, but in the wild rather than in refined gardens.

Even for the locally mild climate, there are plenty of deciduous plants that provide foliar autumn color. Trees are the most familiar. Vines and shrubbery are also popular. Because this mild climate is marginal for some of them, color is likely to be variable from year to year. Unfortunately, some that perform satisfactorily for inland locations may perform less satisfactorily in coastal conditions.

Autumn Sage

50909
Salvia greggii is a modest sage.

Perhaps in the wild, it blooms in autumn. Where it gets watered in home gardens, even if watered only occasionally, autumn sage, Salvia greggii, blooms all through summer as well. If pruned back severely over winter, it starts to bloom even sooner in spring. The tiny flowers are red, rose, pink, peach, very pale yellow, lavender or white. Some poplar cultivars have bi-colored flowers.

Compact autumn sage that does not get much more than a foot tall is uncommon. Larger cultivars get four feet tall and broad, with more open growth. Most get about three feet high and a bit wider. Without severe winter pruning, stems can eventually get twiggy, with sparse foliage on the exterior. The tiny aromatic leaves are less than an inch long, and visually resemble oregano.

Even though it is not native to California, autumn sage is popular for native landscaping because it does not need much water. Just like native sages, it attracts butterflies and hummingbirds.

Rainy Season

 

 

As I mentioned this morning, the first storm since spring delivered a bit more than an inch and a half of rain before dawn on Wednesday, ending the fire season. The second storm is here right now. It is expected to be followed by a continuous series of storms that will provide rain through Monday, showers through Thursday, more rain on Friday, and showers . . . forever!

It is now the rainy season.

The video above shows what rain does. It gets things wet. It is, after all, composed of water. It falls mysteriously from the sky, which, as you can plainly see, is occupied only by a mostly monochromatic gray cloud cover. Seriously! There is nothing else up there. There is no one on the roof with a hose or anything of the sort. All that water just falls from the cloud cover above.

I could not get video of individual raindrops falling. They are too small and too fast. Only a few can be seen indirectly in the video, falling in front of the water cascading from the rusted out gutter. The spots on the video are raindrops that landed on the lens, so were no longer so animate. The cascading water is, of course, an accumulation of many raindrops that fell on the roof.

Besides ending the long fire season, rain also disrupts the slim fall color season, when foliage of certain deciduous trees turns color as the weather cools in autumn. There is not much to brag about anyway. Only a few native trees are moderately colorful. More colorful exotic trees are not very popular because they do not color as well as they do where autumn weather is cooler.P91130K

Before the rain, these birches were a nice clear yellow, but were already defoliating. Their fallen leaves were as pretty on the ground as they were in the trees, but unfortunately needed to be blown. By now, there is likely more on the ground than there is in the trees, but it will need to be blown too. At least it gets to stay on the open ground in the rest of the casual landscape.P91130K+

The only tulip tree here got cool enough to defoliate before the birches this year, but not quite cool enough to color well first. It is a grand tree nonetheless. We do not expect exemplary color in autumn in our splendidly mild climate anyway. The sweetgums will compensate. They are only beginning to color, and should hold some of their foliage rather well through the weather.P91130K++

Slow Color

P91110Autumn is not much to brag about here. It supposedly got just cool enough at night for the minimal requirement of frost, at 32 degrees, but no one noticed. It has been getting to the low 80s during the day. There has been no rain yet, and none is in the forecast. As bland as such weather seems, it is not at all out of the ordinary. Autumn often arrives later than it does elsewhere.

Consequently, autumn foliar color is not much to brag about either. There are only a few trees that reliably develop good color, such as sweetgum, pistache, flowering pear, crape myrtle and maidenhair tree (ginkgo). As reliable as it is, maidenhair tree provides only bright yellow, without the oranges and reds that the others exhibit. None are exhibiting significant color just yet.

There are several other trees that have potential to develop good color, but are not as reliable about doing so. Birch can get almost as brilliant yellow as maidenhair tree does, but does not do it every year. Red oak may turn brilliant orange with a bit of brownish red mixed in, but only every few years or so. On rare occasion, even London plane (sycamore) shows off burnt orange.

Every species has a distinct personality. They each respond differently to different variables. Weather conditions that stimulate good color among flowering cherries may not stimulate good color for bigleaf maples. Dogwoods that colored so well at about the same time last year as the tulip trees, are already nearly bare after minimal color, while the tulip trees are mostly green.

Every few years, if mildly but suddenly chilled, these cottonwood develop a brighter yellow, with less blotching. With slower and drier chill this year, they are deteriorating and falling without much yellow at all.P91110+