a Tale of Two Jacarandas

Jacaranda seedlings from this year will be ready to grow next year.

Los Angeles is about three hundred and fifty miles to the southeast of Los Gatos. Relative to the number of different climates between here and there, the climates of the two specific locations are surprisingly similar. Nonetheless, they are not completely similar. Winter weather is somewhat milder within the Los Angeles region, with only minimal frost. Some coastal climates there lack frost. Also, spring weather there is a bit warmer than here.

Jacaranda mimosifolia perform spectacularly with such mild winter weather and warm spring weather. Without frost, or even with minimal frost, they can grow taller than thirty feet, and eventually grow broader than tall. After defoliating for the end of winter or beginning of spring, they bloom for late spring, immediately prior to refoliation. Their awesomely vivid blue bloom is almost as profuse as their subsequent foliage. No other tree of comparable size compares to their floral color or floral profusion. That is why jacaranda are so much more popular within the region of Los Angeles.

Here, occasional moderate frost inhibits comparable performance. Trees are generally smaller and more compact, with more globular form. Vigorous growth that develops after frost damage can be structurally deficient, but heavy with lush foliage. Bloom is more sporadic amongst such vigorously vegetative growth. Although very pretty by local standards, jacaranda is not quite as exquisite as it is within the region of Los Angeles.

Nonetheless, I am growing some. A colleague brought me a seed pod from which I extracted seed. Fortunately, only a few more than two dozens seedlings survived a late frost last winter. Otherwise, many more would eventually be in need of homes. A few will likely inhabit our landscapes. A neighbor wants a few. Any extra jacaranda trees can be shared with other neighbors, like so much other surplus.

Palms Are A Californian Tradition

Mexican fan palm might still be the most common palm here, but is not native.

Only a few of the  many different palms that can be grown locally are actually common. The Canary island date palm and the Mexican fan palm, which had historically been the most common palms, have unfortunately given palms a bad reputation. Both get too large for small gardens, and need costly maintenance when they grow out of reach.

Since the late 1980s, the formerly uncommon queen palm has become the most common palm. Although it too eventually grows beyond reach, it is still more proportionate to home gardens while young. It has a relatively narrow trunk that is partially ‘self-cleaning’ (which means that old fronds, or leaves, often fall off or can be easily peeled off).

The windmill palm and the Mediterranean fan palm, although no more common now than a century ago, are two of the better palms for home gardens, since they do not get too large, and are somewhat easy to maintain. The Mediterranean fan palm has several sculptural trunks that curve out randomly from the base. Sharp teeth on their petioles make pruning a challenge, but not impossible.

The windmill palm has a straight solitary trunk that is distinctively hairy where old fronds get pruned away. It eventually grows out of reach, but takes many years to do so. By that time, many people allow beards of old fronds to accumulate on the trunks overhead instead of bothering to keep them pruned.

The desert fan palm, which is the only palm that is native to California, is very similar to the Mexican fan palm, but is about twice as stout and half as tall, with a fluffier canopy. Because it grows slower and stays smaller, it would be a better palm for urban gardens, except that it does not like to be watered regularly when mature. It really prefers warmer and drier climates.

Pindo palm and Mexican blue palm would also be great palms for urban gardens, but grow rather slowly before getting big enough to get noticed. In some climates, pindo palm produces strange and messy, but sweet and tasty fruit. Mexican blue palm is one of the most resilient palms, and blooms with really cool long floral tassels that a can drag on the ground from short trees.

‘Feather’ palms, like Canary Island date palm, queen palm and pindo palm, have pinnate (and generally compound) leaves, with small leaflets arranged on solitary midribs. Their fronds must be removed as they deteriorate.

‘Fan’ palms, like Mexican fan palm, Desert fan palm and windmill palm, have palmate leaves, centered around the distal termini of solitary petioles. These are most often pruned away, leaving distinctive patterns of petiole bases, but can alternatively be left to accumulate into thick beards of thatch.

Mexican fan palms are sometimes ‘shaven’ of their petiole bases to expose elegant lean trunks, although the procedure is intensive and expensive. Desert fan palms and some Mexican fan palms drop their own beards naturally.

Early Rain

This could be a sequel to ‘Late Summer’ from yesterday. It happened shortly afterward. It certainly adds another interesting component to this already odd year of weather. Although not impossible, rain at this time of year is rare. Almost all of the rain here occurs between late autumn and early spring.

Weirdly, if rain does occur during summer, it typically does so around the fifteenth of August. Seriously, it is very prompt about that schedule. It typically either begins or ends on that same date.

The first flash of lightning of the storm that started the CZU Fire occurred at 11:59 p.m. on the night of the fifteenth of August of 2020, less than a minute prior to midnight. So, although the storm occurred during the early morning of the sixteenth, it technically began on the night of the fifteenth.

This brief rain shower was minimal, but by local standards, it was surprising. I sort of wanted it to continue long enough to dampen and contain the dust of summer. It might have done so briefly, but could not prevent the dust from becoming dusty again shortly afterward. The aroma of damp asphalt dissipated even before that happened. It was fun while it lasted.

Perhaps this rain shower will be the last of this unusually autumnish weather. Warm and dry summery weather typically resumes immediately after brief rain showers that happen during the middle of August. Technically, for a summer rain shower, it is only half a month late. So far, the forecast does not suggest that pattern, but it has been wrong before, even here. I doubt that there will be any more rain prior to autumn, even if cool autumnish weather resumes until then. But of course, I have been wrong more often than weather forecasts.

Late Summer

Such weather is early this year.

The change of seasons can be boring here. It might seem as if this climate experiences only two seasons. Summer is the primary season, which seems to extend through most of the year, with what seems to be merely a few days of another brief secondary season which is not summer. Perhaps this brief secondary season is autumn, winter and spring, but that is too many letters and big words for such a small season.

That is how those who are familiar with more distinct seasons might perceive seasons of this innately mild climate. Those of us who are familiar with this climate perceive it quite differently. We are aware of the four seasons, regardless of how mundane the transitions between them seem to be. In fact, some might contend that, if autumn seems to be minimal here, it is merely because this climate experiences a fifth season between summer and autumn, which is known as Indian summer.

Indian summer is an extension of summery weather into autumn, and sometimes occurs after summer seems to have begun to succumb to autumn. It does not happen annually, and does not seem to be happening this year, but certainly could. It is sneaky that way.

For now though, autumn seems to be sneaking into the last two weeks of summer, much like Indian summer sometimes sneaks into autumn. Nights have been interestingly cool. Low clouds have been lingering a bit longer after sunrise than they typically do.

However, vegetation that enjoys warmth does not seem to be decelerating for cooler weather. Perhaps such vegetation knows more than the rest of us do about what to expect. Perhaps it is merely more responsive to photoperiod than weather. Regardless, I get the impression that this is how late summer typically is within other climates.

Hurricane Hillary

Rain is expected to start about six or seven in the morning in Brent’s neighborhood.

California is so big that, from here, it extends about four hundred miles to the north and four hundred and fifty miles to the south. That is where San Diego County is, in the southwestern corner of California. It is so far away that the weather there can be very different from here, as it is now that Hurricane Hillary is coming up from the coast of Baja California. While a tropical storm warning is in effect there, typical summer weather is expected here.

Typical summer weather here is dry. Not much rain happens after early spring. Not much happens prior to late autumn. Every few years, a single odd and brief thunderstorm goes through in the middle of summer, leaving no evidence of its downpours two days later. If it were to happen this year, it should happen about now, like it is in Southern California.

Forecasts for the weather in Southern California are quite unpleasant. A friend in Palm Springs was filling sandbags today. Floods and mudslides are expected through a huge area. This is the first tropical storm in California since 1939, and the first ever tropical storm warning. Yet, we will miss it completely here.

I try to remind myself that the historically torrential rain of last winter was no fun. Flooding was a mess, and caused significant damage even in this neighborhood. Nonetheless, even native Californians can start to miss rain late in summer.

Brent will likely telephone at about seven in the morning. It might be raining by that time. It should finish by noon on Monday. Realistically, it will not rain for long. The problem is that rain will be torrential, especially at high elevations out in the deserts, which do not absorb much water. It will be interesting to see what transpires.

Warmth Accelerates Garden Activity.

Spring was mild and started late. Summer if now getting started.

Just like the moon is always either waxing or waning, but is really only full or new for the brief moments in between, the seasons are always flowing from one to the next. Even though it is not yet half way through summer, plants in the garden are already planning for autumn. Summer has been mild, but still warm enough for most plants to do what they need to do by this time of year.

If weeds were not pulled when they should have been in early spring, they really should be pulled now. They have already started to sow their seed for the next generation that will grow at the end of next winter. The ground has dried and hardened since early spring, so pulling weeds will take a bit more effort. That is the punishment for procrastinating.

Weeds that are still somewhat fresh and green may not have dispersed all of their seed yet. If pulled soon enough, their next generation may not be so prolific. Those that have dried have likely dispersed their seed already. Their progeny will be back by next spring.

Pulling out the roots of annual grasses is not as important as getting the roots of perennials like thistles. Heck, they are annuals, so will die at the end of the season anyway. Getting their seed in the priority now. Some people are satisfied with simply pulling the seeded tops off of annual weeds, and leaving the lower portions to die out naturally.

Most fruit trees finish their production sometime during summer. Small fruit like cherries finished some time ago. Larger peaches, although related to cherries, may still be ripening into August. They should be picked as they ripen, not only to get the most use out of them, but also to avoid sharing with unwelcome rodents, birds and other annoying wildlife. The ground under fruit trees should be cleaned of any fallen fruit that might otherwise rot and perpetuate disease. Apples and pears ripen later and into autumn.

Warm season vegetables should be picked as they mature to promote continued production. Leaving extra zucchini on the plants inhibits production of new zucchini, while the old zucchini grow into tough and insipid baseball bats. Leaving extra tomatoes both inhibits new tomatoes and also makes a mess of rotting fruit.

Mild Weather Inhibits Summer Growth

Vegetative growth might be atypically slow.

The weather this year has been a cold hot mess! Both the worst frost since 1990 and the worst storms since 1982 occurred in one winter. Then, cold wintry weather lingered into spring to inhibit spring bloom. Now, cool and mild weather of spring lingers into summer to inhibit summer growth. This particular climate is innately mild, but this is a bit too mild.

Technically, the solstice on June 21 is the beginning of summer. Locally though, summer warmth typically begins about the middle of spring. It typically continues into the middle of autumn. Sometimes, it begins significantly sooner or continues significantly later. This is why the warm growing season here is so extensive. It is also why winter is rather brief.

Unseasonably mild weather obviously has a few distinct advantages. It is comfortable for those who are not so fond of summer warmth. It limits the need to increase irrigation that compensates for aridity and lack of rain. Bloom, although potentially late, stays fresher a bit longer with mild weather. A bit less spring bloom becomes a bit more summer bloom.

Unseasonably mild weather also has a few disadvantages though. Less gardening work is needed to manage desirable vegetation. However, more gardening work is needed to manage undesirable vegetation. Weeds generally need less warmth to grow, bloom and seed. Some desirable vegetation is still too complaissant to compete without assistance.

A few other pathogens likewise exploit this unseasonably mild weather. Slugs and snails hide from arid warmth. They must stay within cool and damp situations through midday. Mild weather allows them to stay out later, and emerge earlier. Their favorite vegetation still grows too slowly to recover from their damage. Tropical foliage is most susceptible.

Fungal disease is similarly more problematic with unseasonably mild weather. A primary difference is that fungal pathogens are about as inhibited as vegetation is. They gain an advantage only because soil stays continuously damp longer. Even without automated irrigation, cool soil dries slower than warm soil. Roots consume less moisture while cool. Roots that consume minimal moisture are generally more vulnerable.

Arid Weather Increases Water Consumption

Chaparral vegetation naturally tolerates arid weather.

Superbloom is brief for two main reasons. It involves native species that know to bloom quickly before arid weather of summer. Also, wildflowers in the wild receive no irrigation to sustain bloom through arid weather. With irrigation, some of such species are capable of prolonging bloom. A few can disperse seed for subsequent generations to bloom later.

That is why California poppy blooms for a longer season within home gardens. It easily performs through much of summer with irrigation. Also, with irrigation, it might regenerate to bloom for autumn after summer dormancy. Seed from earlier spring bloom might grow to also bloom for autumn. Some godetias and lupines perform similarly within cultivation.

Most species within home gardens are exotic though. In other words, they are not native. Those that are native to a similar mediterranean climate respond similarly to cultivation. Generally, some from desert climates do so also, although many dislike extra irrigation. The majority of exotic species actually rely on some degree of cultivation and irrigation.

Such species are native to climates with cooler and less arid weather through summer. Rainfall here is too limited to winter to sustain them through summer. Minimal humidity and warmth increase the need for moisture while it is least available. Cooling summer breezes actually accelerate desiccation. Arid weather certainly has its disadvantages.

As spring relinquishes to warmer and drier summer, irrigation becomes more important. Frequency and duration of automated irrigation must adjust to increasingly arid weather. Shallow root systems, such as those of turf grass lawns, require more frequent irrigation. Deep root systems, such as those of maturing trees, require more voluminous irrigation.

However, irrigation should not be so excessive that soil remains saturated. Many mature trees and shrubs need none at all. Some receive enough from what adjacent vegetation does not consume. Some are satisfied with only occasional irrigation. Turf and annuals require the most frequent irrigation. Yet, even they can rot if their soil is always saturated. Calibration of irrigation requires diligence.

Superbloom Highlights Local Mediterranean Climate

Rosemary can bloom longer with irrigation.

It does not happen often. The average frequency is about ten to fifteen years. However, it occurred in both 2017 and 2019, prior to this spring. That is enough for thirty to forty-five years! The current superbloom is only now finishing locally. It may continue through most of May near the coast farther North. The best bloomers enjoy the Mediterranean climate.

Climate is the typical and seasonal weather pattern of a region. The local Mediterranean climate is typically mild and somewhat arid. Almost all rain occurs between late autumn and early spring. Rain is otherwise rare. Winters are cool but not too cold. Summers are warm but not too hot. Native and some exotic flora knows how to exploit such climates.

Some exotic flora that prefers other climates also seemed to demonstrate a superbloom. Some merely responded to the unusually cool weather last winter. They appreciate more vernalization than they typically experience here. Some species enjoyed the unusually abundant rain last winter. Some species enjoyed both extra rain and extra vernalization.

Native species and exotic species from similar Mediterranean climates are a bit different. Their superbloom happens at the same time, and is also a response to earlier weather. However, it is also a response to later weather. They know that Mediterranean climates get warm and arid through summer. They are in a rush to finish blooming while they can.

Superbloom is how many species accomplish all their annual bloom within a brief time. They begin as soon as cool and stormy wintry weather finishes. They finish before warm and dry summer weather desiccates their flowers. Of course, such bloom may not be so spectacular after typical winters. It is only superbloom after exceptionally wintry winters.

Some species that exhibit superbloom in the wild bloom later for irrigated home gardens. This includes some exotic species from similar Mediterranean climates elsewhere. Such climates are present in small portions of Australia, South America and Africa. Obviously, most Mediterranean climates are around the Mediterranean Sea. Most exotic plants that are most adaptable here are from such climates.

Shasta Lake

Shasta Lake is a large reservoir on the Sacramento River. It contains water for flood control and to generate electricity. Some of the water within is used for agricultural irrigation and, to a relatively minor degree, to supply regional municipal water.

It is a very common misconception that the volume of water within Shasta Lake is necessarily relative to ‘drought’ conditions. Low water level is supposedly indicative of a ‘drought’. High water level is supposedly indicative of ‘normal’ weather conditions, including adequate precipitation. This same misconception seems to apply to all reservoirs in California.

Well, after the rainiest winter since 1982 and 1983, Shasta Lake is still not full. The level fluctuates, so might have been full earlier, or might be full later, but regardless, is not presently full. Water must be released prior to expected rainy weather, which can still occur during spring, in order to accommodate more water to control flooding. Less water may be released as drier weather is expected. Shasta Lake could therefore be fuller or completely full for summer, when almost no rain is expected. The presently observed water level does not indicate deficiency of water any more than a potentially higher water level during summer indicates surplus.

Most of California has a chaparral climate. Some of California has a desert climate. Such climates are naturally dry through summer. It is quite normal. It does not constitute a drought. A drought is an unusually dry weather pattern. It is not so normal.

Contrary to popular belief, California is NOT in perpetual drought. Although droughts occasionally happen, they are not annual events. Dry weather that occurs annually every summer is normal climate. If there is a deficiency of water here, it is because there are nearly forty million people relying on a limited supply of water.