New Zealand and coastal California share many aspects of climate — especially our temperature range and humidity. They tend to get more rainfall over there, especially in the warmer half of the year, than we do.

Many of the plants the Kiwis can grow, we Californians can, too. Palms are no exception. Our friends over at Palmtalk.org have shared a video shot at an established palm garden near Auckland called Landsendt.  It’s “palm porn” in as literal a sense as any G-rated media can be. Remember, virtually anything seen in this video will also thrive in San Francisco and mild coastal areas of the Bay Area and central California. And it’s all safe for work viewing.

Landsendt sub-tropical gardens, Auckland New Zealand

Some of the special plants visible are the colorful-crownshafted Geonoma undata, from high altitudes in the Andes; majestic Ceroxylon quindiuense and C. parvifrons, also from the Andes; groves of New Zealand’s native nikau palms, Rhopalostylis sapida; and cycads like Encephalartos, Macrozamia, and Cycas. Other non-palms spotted include a Pandanus sp. from New Guinea’s highlands, a large-leafed Ficus species (F. dammaropsis? F. auriculata?), and — can it be? — a Cecropia species.

Coconut crowns make an exceptionally graceful silhouette against the tropical skies of Puna, Hawai'i

Polynesian-introduced coconuts thrive in the lava along the Puna Coast of Hawai’i’s Big Island.

We found an interesting article about the ecological change wrought by introduced coconut palms on a previously coconut-free island in the central Pacific Ocean.

It’s sad to think that the coconut palm (Cocos nucifera), a lovely icon of the tropics, can also be a human-introduced invasive species on pristine islands like Palmyra. This atoll, directly south of Hawai’i in a belt of heavy rainfall just north of the equator, has a rich indigenous forest on its sparse land area (4.6 square miles) — and an extraordinary coral reef and lagoon habitat underwater.

The newly coconut-dominated portions of the landscape attract far fewer birds than the native forest, and thus lack the guano-enriched soils of the native forest. Even where native forest plants grow near the coconuts, their foliage, flowers and fruits are less-nutritious than they are when growing in coconut-free parts of the island. Such impoverishment puts dependent organisms like birds and insects at a disadvantage and is likely to reduce biological diversity.

Palmyra Atoll is an unincorporated territory of the USA, administered as a National Wildlife Refuge by the Interior Department.

Palmyra Atoll makes a tracery of green in the vast Pacific. Photo by Ethan Roth

Many people are familiar with the California fan palm, Washingtonia filifera, native to watercourses in the lowland deserts of Southern California. The largest grove is at Palm Springs, and it’s a sight as awe-inspiring as any other botanical wonder of California. “Filiferas,” as we call them here at the Palm Broker, are planted all over California, even up into the foothills of the Sierra Nevada. Lines of them frame Capitol Park in Sacramento. The species has naturalized outside its historical range in California, as at the mouth of the Kern River Canyon near Bakersfield and in Death Valley. A well-grown California fan palm is stately, and an avenue of them, majestic.

Typical California fan palm (Washingtonia filifera) specimens at the Ruth Bancroft Garden in Walnut Creek, California, retaining their dead fronds

Baja California is also home to the California fan palm, and to four other palm species, as well. One of them is particularly well suited to the range of microclimates in the Bay Area — the Guadalupe palm, Brahea edulis. We have one specimen planted here at the nursery that we moved from our Guerrero Street location. Dolores Park is home to an old grove of Guadalupes, too. Other notable Brahea edulis can be found on our Bay Area palm map.

Unlike the desert-dwelling California fan palm, which thrives only in the hotter, drier inland parts of the Bay Area, the Guadalupe palm, native to a foggy island in the Pacific, grows well throughout lowland California — wherever winter lows stay above 22F — even along our foggy coastline. It also grows well and looks beautiful in shade.

Drought-tolerant Guadalupe palms thrive in the shade of a 300-year-old valley oak in Walnut Creek, California

The California fan palm, alas, won’t thrive in shade, and runs a high risk of fungal disease in the cool, humid weather that prevails in San Francisco and anywhere near the ocean and bay. They both thrive inland, as seen in this photo from Sacramento (Guadalupe on left, California fan on right).

So why call the Guadalupe palm “native?”

The state of California is home to portions of four different floristic provinces: Californian, Sonoran, Vancouverian, and Great Basin. To quote the Rancho Santa Ana Botanic Garden:

In nature, the distribution of plants rarely coincides with political boundaries, but rather is determined by the interaction of climate, geology and geography. A regional association of plants that share these growing conditions is called a floristic province.

The Guadalupe palm’s home falls within the California Floristic Province. The island shares many species with the Channel Islands (e.g., Santa Catalina) and mainland California. Guadalupe palms grow amidst indigenous Monterey pine, Pinus radiata var. binata; toyon, Heteromeles arbutifolia; sword fern, Polystichum munitum; California juniper, Juniperus californica; and members (some endemic) of such typically Californian genera as Cupressus (cypresses), Eschsholzia (California poppies), Ceanothus (California lilac), Arctostaphylos (manzanita), and Eriogonum (buckwheats).

To be accurate, Guadalupe palms used to grow with these plants, but many became endangered or were extirpated by more than a century of feral goat browsing. The destruction has now ended with the removal of the goats as part of a restoration project, and plants are responding with rapid growth.

So, in the sense of being a species from the botanical province most characteristic of California, Brahea edulis is native — just not to the state of California.

OK, it’s a technicality, but a fun one to contemplate (palms with pines and cypresses and oaks — oh my!). What matters, though, is that the Guadalupe palm is a lovely species that thrives in all parts of the Bay Area, as long as you can give it some decent drainage, and irrigation for the first several years of its life until it’s established. Besides climate compatibility, it offers a nice scale (stays below 30 feet tall, mostly below 15), good performance in a container, and a clean, green look, thanks to its tendency to shed old leaves. No nasty thorns, either. We often recommend it over Washingtonia and some other, more common, palms.

A well-kept Brahea edulis in San Francisco's Bernal Heights neighborhood

This avenue of Guadalupe palms at the Huntington Botanical Gardens in Pasadena is perhaps the most extensive formal planting of the species in California.

Trachycarpus fortunei, the Chinese windmill palm, is one of the most cold-hardy of palms. Gardeners in London, Vancouver, and Tokyo grow this palm to perfection. It looks really neat in the snow.

Trachycarpus wagnerianus, a close cousin we like to call the “waggie” palm, makes an durable container specimen. Isn’t this little family of fan palms endearing?

It’s also a palm that produces fascinating flowers this time of year. Ours here in the nursery are pushing out new flowers right now.

Flowerstalks of waggies emerge among the leaves in the crown.

The bracts are the pale-yellow, leathery structures enclosing the mass of flowers.

Each of the corn-like grains is an individual, unopened flower.

Waggies are such pretty, durable palms. They look particularly nice in groves. Even in a small city garden they can make a lovely grouping.

Waggies -- Trachycarpus wagnerianus -- have elegant, sculptural leaves.

We were pleased to see how popular they are in Japan (where they originated) — and how well they fit into tiny Tokyo city gardens. Their Japanese name is “toujuro.”

A typical waggie (toujuro) in Tokyo's Nakano District

Acacias are among the showiest blooming trees we can grow in the Bay Area. Fuzzy golden orbs and cylinders emerge suddenly on many species from winter into spring. Because these spectacular blooms often coincide with the shedding of airborne pollen by pines, oaks, and cypresses, people think they’re allergic to acacia, but usually it’s the conifers and oaks that are causing all that itchy sneezing.

A flowing 15-gallon-size Acacia boormanii was the first to go gold here in the nursery this January — and admiration seems to be trumping complaints about allergies. The profuse lemon-yellow flowers smother the lush mass of fine, grey-green phyllodes (leaflike structures common to many acacia species). This species is useful as a multi-stemmed screening tree, growing to about 15-feet tall but keeping foliage to ground level. It’s amenable to hard pruning nearly to the base every few years, or to training up into a cluster of sculpted trunks with clouds of foliage above. It will tolerate clay soils, and thrives in deep, well-drained soils. A little bit of summer water, especially inland, will keep it looking gorgeous.

Acacia boormanii, the Snowy River wattle, in January bloom

The intensity of acacia bloom in midwinter always comes as a jolt. The invasive Acacia dealbata, ubiquitous in suburban areas of the Bay Area and elsewhere in California, produces acid-yellow masses of flowers starting sometimes as early as December. (On the French Riviera it’s celebrated as “mimosa.”) You see similar flowers on the common San Francisco street tree, Acacia baileyana, offset by feathery, purple-grey leaves. The color grabs attention like a visual siren.

The hairy wattle (you wonder why we stick to botanical Latin?), Acacia vestita, is another of our favorites, planted at the front gate of the nursery.

Acacia vestita just beginning to bloom in mid-January 2010

By contrast with Acacia boormanii’s fluid, cloud-like form, Acacia vestita’s shape is unmistakable. Its weeping, ropy branchlets hang nearly to the ground, especially in youth. They bear silky blue-grey phyllodes in the shape of tiny, pointed, gibbous moons that contrast beautifully with the apple green skin of the branches and trunk. Growing quickly to 12 to 15 feet in height and width, it looks a bit like a green Mr. Snuffleupagus from Sesame Street. Okay–it’s a lot prettier than that, but there is a resemblance. Like most Australian acacias, it’s drought-tolerant and requires no fertilizer and will tolerate temperatures into the low 20s Fahrenheit.

Splashes of fragrant winter gold emerging now feel like that moment when a free dessert comes compliments of the chef. On top of a perfect meal, we didn’t expect or need it, but boy is it delicious.

We’re at the moment in San Francisco’s seasonal growing cycle when the relative quiet of the Thanksgiving-to-winter-solstice period breaks into smashing bloom with acid-yellow Acacia baileyana and Acacia dealbata, deep-sapphire early ceanothus, and delicate plum blossoms (annually finding their raison d’être).

We’re always looking for additions to these common midwinter elements and their glorious signs of mediterranean-climate flourishing. Down at the Presidio, in the casual median strip garden of Kennedy Avenue, Banksia praemorsa presents the most-stunning show in town right now. It’s a Western Australia native that loves sandy soil and even seaside conditions. Imagine banks of these 12-foot shrubs in Pacifica and Daly City and the outer Sunset and Richmond districts.

The evergreen foliage is quite pretty, too. It appears clipped by pinking shears, a form that inspires its species name, praemorsa. New growth emerges covered in bronze fur.

This Banksia's stems lean and rise upward.

This bush is in all stages of bloom, from bud to full glory, and the birds are loving it.

Not far from our store, in the Sunnyside neighborhood (near Glen Park), is an extraordinary grove of 100-plus-year-old palms surrounding a historic conservatory-like pavilion. It’s called the Sunnyside Conservatory, and, built in 1898 as a garden structure on a large country estate (before the city engulfed the area), it’s on San Francisco’s list of landmarks.

Most of the palms are Phoenix canariensis, the Canary Island date palm. Planted close together, their trunks lean gently away from each other in an unusual presentation for this species in our area. Most often we see them as very upright avenue trees.

Among these beautiful trees is a single spectacular specimen of the Chilean wine palm, Jubaea chilensis, with a huge, silvery, cigar-shaped trunk and an elegant crown of gray-green fronds. You can see its fat trunk on the left in the photo below. Jubaea is one of the two or three best-adapted palms for San Francisco and the Mediterranean climate zones of California — which is most of the heavily populated part of the state. Endangered in central Chile, its native habitat and a fellow-Mediterranean climate, it thrives in our summer drought, wet winter cold, and foggy coastal winds. It also produces tasty miniature-coconut-like nuts. Killing it for sugary sap to make wine is what eliminated the tree from vast areas of its habitat, although some in Chile have now devised a way to draw the sap without felling the palm, and the few remaining natural groves there are protected.

As rare as this spectacular species is, another landmark specimen grows not more than a mile away, on Yerba Buena Avenue near Monterey Boulevard. Was there a connection between their planting — maybe 19th century country neighbors shared rare plants? As part of the Sunnyside Conservatory’s renovation, a young Jubaea has also been planted in the garden. Because it is drought-tolerant and immune from the diseases that can attack the Canary Island date palm, planting young Chilean wine palms is a smart long-term investment.

The San Francisco Recreation and Park Department with the help of the Friends of Sunnyside Conservatory has been renovating the garden and structure over the past couple of years,  and the Friends are throwing a grand reopening party at 11am on December 5, 2009. What a great chance to enjoy a beautiful public palm garden!

Goodness, our strong tree opinions have landed on SF Curbed.

We’re in favor of any way to improve tree selection for San Francisco.

We had a conversation with our gardener friend, Mike, last weekend about deciduous trees — the beautiful, the useful, the disappointing, and the ugly. It’s autumn, and along our latitude (37 to 38 degrees north), many deciduous trees are starting to change into their stunningly colorful foliage before going dormant for winter. In San Francisco, not so much; our climate is too mild to allow most deciduous trees to put on the show they’re famous for in the Sierra Nevada, Japan, or the Appalachians, all of which share our latitude but not our climate. We have chilly summers and mostly frost-free winters here. Measured as the annual range of average temperatures, our climate’s mildness (but not warmth!) rivals that of Honolulu’s and San Diego’s. Our warmest month, September, isn’t very much warmer than our coldest month, January, and many deciduous trees need greater seasonal extremes.

Some deciduous tree species are lovely exceptions in SF, but for this post, let’s talk about gripes.

One species that’s a bugaboo for us is Pyrus calleryana, the Callery pear. It’s a classic indicator plant for our area, one that performs differently in different microclimates. In the right climate, which is much of the temperate zone of the United States, this species and its many selections, like ‘Bradford’, and ‘Chanticleer’, produce glorious fall color, burst into clouds of bloom in early spring, and grow to become respectable 40-foot trees. At the San Francisco Flower & Garden show last March, held at the San Mateo Event Center, we admired dozens of these trees in their silvery-white exuberance. We have seen the same healthy bloom every spring at a Marin County mall, the Town Center Corte Madera, where the pears also produce equally stunning orange foliage in fall.

Callery pear trees (Pyrus calleryana) in San Mateo, California

Both of these places are within 20 miles of downtown San Francisco, but Callery pears in the city perform poorly. Trees often hold their foliage while simultaneously pushing out insignificant blooms and popping premature leafbuds well into winter (and even spring), rarely coloring to any pleasing shade, rarely going fully dormant until February, if ever. When our neighbors around the Bay Area are thrilling to the March sight of pears in bloom, our SF trees are sputtering and won’t look okay until July. Perhaps 20 percent of SF’s Callery pears perform as hoped — except that even those 20 percent rarely approach the treelike dimensions of their suburban siblings. And, this last summer, we saw many damaged by fireblight. The irony of this post is that at no time of the year do they look better in San Francisco than now: Eventually through June and July they leaf out (even if they barely bloom) and get nice and glossy green.

It’s a testament to the low standards of wind-beleaguered San Francisco gardeners and landscape designers that few people recognize the poor performance of this tree. Drought, lack of heat, wind (plus poor soils!): Our climate is special, and that often means that trees grown for mass distribution, like Callery pears, are not actually suited to our mild winters and chilly, windy summers. It’s not because of where they’re grown (Oregon, or the Central Valley), but because of the tree’s preferences. But they’re available in quantity at a good price, reference books list them as hardy in our climate zone, and thus they get chosen for planting plans. Rumor has it that Callery pears have been chosen for the current reconstruction of Valencia Street between 15th and 19th streets. Sigh.

Our larger gripe is that we’re planting unhappy trees where beautiful, thriving trees could be grown. Unlike, say, the London plane tree, Platanus X hispanica, which (aside from the ‘Yarwood’ selection) trumpets its maladaptation with powdery mildew, rust and anthracnose weeks after leaves develop, Callery pear simply limps and mopes for six months of the year. In the second-densest city in the US, it’s an opportunity cost; mopey trees take the place of thriving trees, and depress the interest in planting more trees.

Perhaps the overarching gripe we have is inattention to place. Not paying attention to the performance of plants in specific microclimates leaves our city with uglier, unhealthier trees whose commonness cannot contribute to the character of this (climatically weird) place.

Another time, we’ll talk about deciduous trees that we love for San Francisco.

The New York Botanical Garden’s Plant Talk blog spotlights the “tree of life” — the coconut palm, Cocos nucifera.