We gave a talk today about palms — with botanical facts, ideas for using them in the landscape, and information on growing them successfully. We handed out notes to the people who attended, presented below:

Palms 101

Selecting palm species

• Screen by these criteria: aesthetic appeal, design function, frost-tolerance, heat requirements, wind tolerance, sun tolerance, and water needs. Most soils can be amended.

Exceptional choices for the cool-summer Bay Area:

Rhopalostylis spp. (nikau & Norfolk palms)

Parajubaea spp. (Andean “coquito” palms)

Trachycarpus spp. (windmill palms)

Brahea edulis (Guadalupe palm)

Chamaedorea spp. (bamboo palms)

Livistona spp. (Australian & Chinese fan palms)

Jubaea chilensis (Chilean wine palm)

Howea forsteriana (kentia or paradise palm)

Hedyscepe canterburyana (umbrella palm)

Ceroxylon spp. (wax palms)

Arenga micrantha (Tibetan sugar palm)

Excellent choices for inland extremes:

Butia odorata (pindo palm)

Brahea spp. (Mexican blue palm and many others)

Jubaea chilensis (Chilean wine palm)

Chamaerops humilis (Mediterranean fan palm)

C. humilis var. argentea AKA “cerifera” (blue Atlas fan palm)

Dypsis decipiens (Manambe palm)

Livistona decora (ribbon palm)

L. nitida (shiny Australian fan palm)

L. australis (Australian fan palm)

Trithrinax spp. (Argentine fan palm)

Sabal spp. (palmettos)

Trachycarpus spp. (windmill palms)

Phoenix dactylifera (true date palms)

Washingtonia filifera (California fan palm)

Rhapidophyllum hystrix (needle palm)

Nannorhops ritchiana (Mazari palm)

For ocean-side or windy bayside locations:

Butia

Chamaerops

Brahea edulis

Phoenix canariensis

Jubaea

Trachycarpus wagnerianus

*Worth a try: Parajubaea, Howea, Livistona nitida, L. australis, Rhopalostylis, Phoenix reclinata, P. sylvestris, P. dactylifera ‘Zahidi’ & ‘Medjool’, Sabal, Trithrinax

Banana-belt treats for the Mission, Telegraph Hill, Oakland, Tiburon, Los Altos Hills, Santa Cruz hills:

Pritchardia minor (Hawaiian fan palm)

Archontophoenix cunninghamiana (king palm)

Dypsis baronii (hardy areca palm)

Caryota maxima & C. obtusa/gigas (fishtail palms)

Ravenea glauca (mini-majesty palm)

Rhapis spp. (lady palms)

Livistona chinensis (Chinese fan palm)

Notes on common species:

o       Washingtonia: W. robusta, the Mexican fan palm and the “cockroach” of palms, will tolerate but not look good in the chilly fog belt, while it will thrive but get occasional winter foliar damage in the coldest inland climates. It’s also often the wrong selection because it gets too tall. The California fan palm, W. filifera suffers fatal fungal infections anywhere with significant summer marine influence (zones 15-17). In very wet-winter regions its crown suffers through winter & spring, but in inland extremes it thrives.

o       Phoenix canariensis: Because of the risk of fatal fusarium wilt on Canary Island date palms, it’s best to use Jubaea chilensis wherever possible instead; specimens of the latter are expensive and rare, however.

o       Phoenix dactylifera: Selections ‘Zahidi’ and ‘Medjool’ tolerate our cool, humid summers better than the cheaper and more common ‘Deglet Noor’. True date palms can also replace Canary Island date palms where specimens are needed.

o       Syagrus romanzoffiana: the queen palm is a good choice for a fast-growing, narrow, medium-size palm tree where summers are slightly warmer than the foggiest districts and moisture and fertilizer can be provided. In windy, chilly-summer neighborhoods west of Arguello or Masonic it looks terrible. Inland it will thrive and quickly reach maturity but can be killed by the rarest 30-to-50-year freezes. It’s at its best where winter temperatures stay above 25F and summer highs consistently surpass 70F.

o       Trachycarpus fortunei: The Chinese windmill palm can tolerate drought, wind, and some neglect, but at the expense of looking trashy and parched. The best-looking Chinese windmills get even moisture, some shade when young, and fertilizer that includes magnesium. They also benefit aesthetically from group planting and you can give them an updated look by pruning off the furry leafbases. Prettier cousins are T. wagnerianus, T.  martianus, and T. latisectus.

Growing Palms in the Bay Area

• Good drainage & consistent water: few palms tolerate drying out, and few tolerate cold, wet roots.
• Fertilizer: Apply NPK 3-1-3 + 1 magnesium in March, June & September.
• Plant small for best adaptation and speediest growth.
• Palms start growing slowly and accelerate.
• Good to plant slow-growing species large.
• Palms are slow to adapt to increased light levels.

Planting & Transplanting

• Spring-summer best season.
• Never manipulate rootballs.
• Tight fit with foundations & walls works fine.
• Keep original rootball moist and irrigate surrounding soil to encourage establishment.

Design

• Repetition & naturalism: in groves, at differing heights
• Not just trees: shrubs, screens, containers, understory foliage, and the role nothing else can match, palm.
• One palm does not equal one tree.

Portraits of Random Rare Palms for SF Bay Area:

Parajubaea torallyi var. torallyi

Pasopaya Palm

Coco

A fast-growing, very rare, majestic tree from high in the Bolivian Andes. Looks like a husky coconut palm. Give it full sun, good drainage, ample water, regular fertilizer, and stand back and watch it develop into a graceful and substantial palm with a hefty, fiber-clad trunk and finely divided pinnate leaves. Once established, it will tolerate drought. Can reach 20 feet tall in 15 years. Produces edible miniature coconuts. Enjoys the Bay Area’s cool and warm microclimates and will tolerate moderate frosts. Plant as young as possible and with no root disturbance. Minor seashore tolerance, but otherwise adaptable from the foggy Outer Sunset to Walnut Creek (Sunset zones 14-17).

• Feather palm; no crownshaft
• Max height: 80 feet in 100 years
• Max crown breadth: 20 feet
• Extremely rare
• Majestic
• Fast growth
• Hardy

Parajubaea cocoides

Coquito

California Coconut

This exquisite and rare coconut look-alike graces the colonial streets of Quito, Ecuador, and other Andean cities. No other palm looks more like a coconut overall. It produces a lush crown of shiny, dark-green leaves atop a rather slender trunk. Extinct in the wild, it’s one of the fastest growing palms for San Francisco and other bayside climates, requiring our cool summers to thrive. Tolerates light frosts. Plant as young as possible in its permanent, full-sun location – it will not tolerate root disturbance – provide ample water and fertilizer, and within 15 years it will be a 15-foot tree producing one-tenth-scale edible coconuts. Not likely to tolerate seashore conditions, but otherwise it is happy in the foggiest locales as well as in mild areas ringing the Bay (Sunset zones 16-17). Once established, it will survive occasional drought but prefers regular water.

• Feather palm; no crownshaft
• Max height: 50 feet in 75 years
• Max spread: 17 feet
• Edible seed
• Rare
• Uniquely adapted to SF Bay Area climate
• Fast growth

Hedyscepe canterburyana

Umbrella Palm

Big Mountain Palm

One of the most colorful, clean-looking and graceful palms we can grow in San Francisco, this native of Australia’s tiny Lord Howe Island in the South Pacific develops a powdery blue-green trunk and crownshaft, apple-green foliage, and lipstick-red fruits the size of robin’s eggs. It prefers a bright, semi-shaded position in well-drained soil, and regular water and fertilizer. Its slow growth and modest proportions make it perfect for small gardens, reaching 10 feet in 30 years, with a crown spanning five feet. It tolerates light frosts but should be planted only in San Francisco and the most protected climates of other bayside and coastal cities like Sausalito, Belvedere, Oakland and Berkeley (Sunset zone 17). Minimize root disturbance upon planting. Thrives in the foggiest neighborhoods, but not especially tolerant of direct coastal exposure.

• Feather palm; crowshaft
• Max height: 30 feet in 75 years
• Max spread: 3-5 feet
• Exceptionally beautiful
• Rare

Lepidorrhachis mooreana

Little Mountain Palm

The perfect fog-belt palm, this extraordinarily rare species grows in one half-square kilometer area atop a windy, mist-draped mountain on Australia’s tiny Lord Howe Island in the South Pacific. It’s a fast-growing, small tree that prefers “full fog” exposure west of Twin Peaks and Divisadero, and a bright but not roastingly sunny spot in banana belts of San Francisco and milder bayside and coastal climates (Sunset zone 17). In full shade it will grow happily but more slowly. Adapted to wind, but not direct coastal exposure. Its diminutive size (to six feet tall), clean, exotic appearance and adaptation to our unique climate make it an exceptional plant for San Francisco urban gardens, especially in those foggy zones.

• Feather palm; incomplete crownshaft; self-cleaning
• Max height: 6 feet
• Max spread: 3 feet
• Extremely rare
• Uniquely adapted to SF Bay Area climate

Ceroxylon alpinum

Coffee-Belt Andean Wax Palm

One of the endangered wax palms of the Andes, this tall Columbian cloud-forest tree will function as a luxuriant foliage element for decades before developing its slender trunk and becoming a spectacular skyline feature. Plant in bright shade or half-sun in rich, well-drained soil, water regularly, and it will steadily produce long, dark-green, glossy, silver-satin-backed leaves. Tolerant of light to moderate frosts, it is best in foggy coastal and humid bayside climates (Sunset zones 16-17 and mild, redwood-dominated parts of 15). Not tolerant of direct coastal exposure.

• Feather palm; loose crownshaft; self-cleaning
• Max height: 100 feet in 100 years
• Max spread: 15 feet
• Rare
• Exceptionally beautiful
• Uniquely adapted to SF Bay Area climate

Livistona nitida

Carnarvon Palm

A cold-hardy and beautiful rare fan palm from Queensland, Australia, this fast-growing species is adaptable to inland as well as bayside and even fogbound climates. The well-proportioned, elegant crown grows atop a tall, ramrod-straight, slender trunk. Plant in full or half sun in well-drained soil, water moderately, and fertilize regularly for speedy growth to 10 to 15 feet in 15 years. Probably at its best in warm-summer areas, it will also provide great satisfaction in foggy zones (Sunset zones 8-9, 14-17).

• Fan palm
• Max height: 100 feet in 100 years
• Max spread: 18 feet
• Rare
• Hardy

Chamaedorea plumosa

Plumosa Palm

Baby Queen Palm

The fastest-growing, most adaptable, and best-scaled palm for small gardens, this delightful native of Chiapas, Mexico, tolerates light to moderate frosts, deep shade or nearly full sun, and wind, among other bugaboos of San Francisco gardening. Its fluffy leaves quickly rise on a thin green stem to create a languorous, weeping crown in deep shade, or a crown resembling a small queen palm in full sun. It appreciates ample water and fertilizer, but, once established, it will tolerate dry periods. Shoehorn it into narrow light wells, or plant it out to give vertical definition in broad, exposed spaces. In the windiest and coldest districts, plant in a protected lee spot, but otherwise it’s adaptable to most urban and coastal Bay Area climates (Sunset zones 15-17).

• Feather palm; crownshaft
• Max height: 20 feet in 15 years
• Max spread: 3 feet
• Rare
• Small palm for small gardens
• Versatile
• Fast-growing

Transplanting palms is pretty darn easy, but if you follow the procedures that are best for planting woody trees and shrubs you can slow their establishment or even kill certain species.

The University of Florida IFAS Extension has published a useful series of articles on palm cultivation, including one on transplanting palms by Timothy K. Broschat. It’s full of interesting photographs and clear info.

Because palms continually produce new roots from the base of the trunk, there’s no need to cut or unravel the rootball of containerized palms when they go into the landscape. And because new roots only develop from the base of the trunk, planting palms with their roots exposed can thwart the development of new roots and thus the healthy growth of the plant.

We see lots of palms planted too high and languishing, and we’ve made the mistake of ripping apart a rootball and waiting years for healthy new growth to emerge from the crown of leaves.

Somebody set fire to this Chinese windmill palm (Trachycarpus fortunei) on 21st and Folsom streets in the Mission District. It used to have a full complement of green leaves and a thick skirt of straw-colored dead leaves. Now it’s almost schematic.

This species of palm is one of the most hardy of all. It tolerates temperatures as low as 10F, sometimes even lower, and sheds snow like an A-frame. Though it prefers even moisture, it will tolerate drought; though it looks prettier in some shade, it grows well in full sun, too; while it’s best in well-drained soil, it seems to tolerate growing at creeksides and in clay. It does not do well in extremely hot desert and tropical environments.

In the aftermath of its pyromaniacal abuse, it’s already showing signs of regrowth.

A special appeal of the Chinese windmill palm is its showy spring flowerstalks (“inflorescences”). What a delightful surprise to see that after having its leaves devoured by fire, the tree still has plenty of stored energy for flowers. Maybe it will even make fruits.

If you look carefully into the skeletal crown you’ll see the green of the newest emerging leaf. The solitary leaf bud of this tree, located deep in the heart of the trunk apex, has not suffered and will be able to produce an entirely new crown of leaves. It’s fascinating to see the structure of the leaf arrangement laid bare by the fire, with only the thick petioles (stalks that connect the fans to the trunk) remaining after the ablation of the thin blades. It will be interesting to watch the tree regrow over the next couple of years.

A smart way to use this species as a street tree is to plant two or three of different heights to a single tree well. The repetition and correspondences between these smallish trees is more pleasing than a solitary exclamation point on the sidewalk.

We sell the species in 15-gallon containers and as boxed specimens.

Thanks to James DeVinny of San Francisco’s Bureau of Urban Forestry for the photos.

There’s a scourge destroying trees in the San Francisco Bay Area. It’s a tiny insect, a thrips, called Klambothrips myopori, and it destroys only one kind of tree: Myoporum laetum. The Maori name for this New Zealand native plant is ngaio, and it’s a self-effacing workhorse found in landscapes all around the Bay.

Fast-growing and tolerant of drought and intense coastal expPostsosure, myoporum has been a useful street tree, a good big hedge, and a billowy large shrub in no-water and low-water landscapes. Its bright, almost succulent evergreen leaves and fragrant white flowers flecked with lavender contribute a lushness to the often gray or olive tones of no-water landscapes. In Southern California, myoporum has become an invasive pest in waterways, especially near the coast, but in the Bay Area it’s not especially aggressive, though here’s an example of one growing at Calera Creek in Pacifica.

Wholesale growers in Santa Barbara have introduced a new variety of this species called Myoporum ‘Green N Clean’ that resists the thrips. However, because of the species’s invasive tendencies and the newness and thus limited availability of this thrips-resistant cultivar, now’s a good time to consider trees that can serve similar functions in the landscape.

In the Australian genus Melaleuca, tea trees, the many species can range from sprawling shrubs to upright trees; several can work well as fast-growing hedges and dome-shaped trees that tolerate moderate sea winds in the Bay Area. Many tolerate wet soils while offering good tolerance to drought as well. Many of them produce pleasing and even showy flowers. The snow-in-summer tree, Melaleuca linariifolia, makes a dome-like canopy with its tiny green leaves and its thick trunk covered in spongy, pale, peeling bark. In June pale-cream flowers cover its crown so thickly as to earn its common name. It’s not nearly so fast a grower as myoporum, but it’s also less prone to breakage and not known to be invasive in California. Other melaleucas that can take the place of Myoporum laetum include Melaleuca styphelioides, prickly paperbark, a slightly weeping variety with bristly leaves that can get much taller (70ft) but otherwise similar to M. linariifolia; and Melaleuca armillaris. The latter makes a luscious, sprawling informal hedge or can be trained into a wonderful tree. Unlike the previous two “paperbarks,” its bark resembles that of a linden or an American elm, with lovely sinuous striations developing over time, and its cream-colored flowers resemble bottlebrushes in form.

Another Australian tree that can serve in some of myoporum’s roles is the water gum, Tristaniopsis laurina, especially the broad-leafed variety called ‘Elegant’. Its resemblance comes in the form of deep, shiny green foliage and fairly good tolerance of coastal winds. Its rounded profile in youth also adds to the similarity, though its ultimate size surpasses that of myoporum. Also pleasing, and unlike myoporum, are its fragrant golden flowers and jigsaw-puzzle-like peeling bark.

For tolerance of salty and foggy winds, few plants can match Myoporum laetum. The drought-tolerant New Zealand Christmas tree, Metrosideros excelsa, bears up well in very foggy and windy districts of San Francisco but has not been used so extensively as myoporum on the front lines of coastal exposure in the Bay Area. In its home country it’s frequently photographed hanging out over salt water, and its Maori name, pohutukawa, means “sprinkled by spray.” These adaptations as well as its pleasing gray-green foliage and red bloom in spring and early summer should earn it more frequent planting in the harshest seaside places where myoporum has until now ruled. The downsides to this tree are its eventual size, ranging as tall as 70 feet and at least as wide, and, for some people, the aerial roots that hang down from its branches and sometimes develop into secondary trunks.

Natives such as Garrya elliptica (tassel bush), Rhus integrifolia (lemonade berry), Rhus ovata (sugar bush), and Malosma laurina (laurel sumac) can serve some of the shrub functions of myoporum in coastal areas. In slightly more protected spots, coast live oak (Quercus agrifolia), California bay (Umbellularia californica), and toyon (Heteromeles arbutifolia) can reach tree-like proportions where salty winds have influence. For a showy, exotic alternative, consider planting Banksia praemorsa, the cut-leaf banksia. In its habitat on the south coast of Western Australia it is subjected to powerful winds off the Southern Ocean. Few plants that can stand up to chilly, salty sea winds, impoverished soils, and a long, dry summer produce such a remarkably beautiful flower cluster on such pleasing foliage.

Ocean Beach coffee haven Java Beach Café is spawning a new restaurant, Beachside, on Judah and 48th Avenue, a block away from their La Playa mother ship. They’re throwing a big opening block party on Saturday, August 27. In keeping with plantings we helped with a couple of years back, the owners, Buffy & Pat Maguire, picked colorful Cordylines (New Zealand cabbage trees) for their new street trees. Matti (Flora Grubb Gardens colleague, Far Out Flora blogger, and Java Beach neighbor) took photos back when the site was still under construction:

Love the movement of the photo. Nothing’s more characteristic of the site than ocean winds, which these plants will have the gumption to tolerate.

Here’s an article in the Ocean Beach Bulletin with the full report on the Maguires’ new restaurant.

Cordyline australis, one of the parent species of these Cordyline ‘Dark Star’, grows happily by the sea in its home range, New Zealand, a land whose ocean winds may be even more severe than San Francisco’s. Thriving alongside will be succulent Aeonium ‘Rubrum’ from the Canary Islands (where they’re nurtured by misty fogs and occasional winter rains), and jade-like soft-tipped Yucca elephantipes ‘Jewel’, a curiously adaptable tree yucca from Central America. It’s so satisfying to use tough-as-nails plants that provide a lush, colorful accent in a horticulturally stressful climate.

Beautiful cladding from weathered Wine Country structures has transformed our side room into a cozy “barn” of garden goodies.

You can see the kids’ section in the foreground of the photo below:

I love this Esther pot with one of our favorites, the snake plant (Sansevieria cylindrica). It’s quite a bold combination against the weathered paneling.

Come visit us and see the new space. Flora and her team have made a big effort to make a warm welcome for you. There’s a bunch of new planters, hats, toys, plants, and other goodies to go along with the new ambiance.

The skies may be threatening snow, but flower buds on our 15-gallon Pittosporum napaulense plants are promising the show below in a couple of weeks:

Golden fragrance is an evergreen, low-branching tree from the Himalayas (including Nepal as the species name indicates) that tolerates temperatures dropping occasionally into the low 20s Fahrenheit. Have you ever seen this tree in local gardens — or in the Himalayas?

Its glossy, deep green leaves remain pleasing even in phases when the tree is out of flower. Flowering can be quite extended in our cool-summer climate. We have seen it bloom in spring, summer and fall at the San Francisco Botanical Garden (Strybing Arboretum). The mind-boggling array of treats like this that we can enjoy in our climate always delights us.

Regular irrigation and normal drainage will make Pittosporum napaulense happy. Occasional applications of rich mulch or balanced fertilizer will keep it robust.  Plant it near a window, door, deck or patio for maximum enjoyment of its luxuriant charms.

Come visit in the next few weeks to imbibe its fragrance.

For all our complaints about summer fog and wind, we who garden in San Francisco’s mild-winter climate get the chance to grow delicious things that will tolerate few other locations north of Santa Barbara. One example is Ficus auriculata. In a warm location on the east side of the city — like North Beach, the Mission, or Bernal Heights — this small tree with heart-shaped leaves thrives in a container or even in the ground. Other spots in the Bay Area where this dramatic fig is worth growing include Sausalito, Belvedere, and Tiburon in Marin; Berkeley, Oakland, and Alameda in the East Bay, and a few favored frostless hillside locations along the coast and around the bay. Unfortunately its trunk-borne figs are not tasty.

We love how it looks on the patio at Skool, restaurant in the Design District of San Francisco with an inventive fish-centered menu. Piotr Mazurek, of Garden Fantasia, designed Skool’s patio garden. Once again Piotr blows us away with his bold plant choices and combinations, convincingly expanding the palette for San Francisco gardens and creating a very special secret garden.

We’re excited about a number of small trees we are bringing into the nursery next week.

Metrosideros collina ‘Springfire’ is a luscious, evergreen flowering tree or shrub for mild coastal climates like San Francisco, Berkeley, and Stinson Beach. You may recognize the genus name, Metrosideros, from the common coastal street tree, Metrosideros excelsa, also known as the New Zealand Christmas tree or pohutukawa. Well, erase that image from your mind: Springfire has much showier orangey-red blossoms and lusher fuzzy green foliage. Metrosideros is also the genus in which the ubiquitous Hawaiian native tree, ohi’a lehua (Metrosideros polymorpha) resides.

(Take a look at the picture above on Flickr.)

Pure sand, rich loam, and even clay soils are suitable for this species, and fertility is rarely an issue. The more sun it gets, the more it will bloom. Exposure to salty sea wind is no problem. Once established, it won’t demand a lot of water, but will certainly grow more quickly with regular irrigation. It also makes a nice hedge.

(Check out the above photo on Flickr.)

We’re excited to be selling the rare weeping Pittosporum angustifolium, a very drought-, heat-, and frost-tolerant small tree that’s widespread in interior Australia. It’s best for inland locations in Central and Northern California, too.  Its shiny linear leaves hang on a narrow, upright tree with weeping branchlets and silvery bark. Aussies call it “native apricot” because its small bright fruits resemble apricots (but aren’t edible). The open crown allows a lot of light through and casts animated shadows on the ground below. Thanks to its narrow profile, it fits into small gardens and sidewalks. David Feix, one of the Bay Area’s most thoughtful and adventuresome landscape designers, recommends this plant for areas with a touch more heat than the fog belt of SF/Berkeley/Oakland.

Walking the streets of San Francisco, you may have notice a variety of intermingling jasmine-like fragrances. It’s an under-celebrated quality of the city.

Pittosporum trees are the source for many of these sweet scents. Several species are planted as park and garden trees, but Pittosporum undulatum, “Victorian box,” is the commonest street tree. Clothed in lush green leaves marked by an undulating edge, it produces small, heavily scented, creamy-white blooms at least four times a year in San Francisco. Its native home is moist forests of Australia’s southeast Queensland, eastern New South Wales, and eastern Victoria states.

Lots of pittosporums make good garden plants. Fragrance is just one selling point.