Sabal riverside

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Sabal (SAH-bahl)
palmetto var. 'riverside'
Riverside, CA. Photo by Brad-Tampa.
Scientific Classification
Genus: Sabal (SAH-bahl)
palmetto var. 'riverside'
None set.
Native Continent
Habit: Solitary
Leaf type: Costapalmate, with recurving leaf.
Survivability index
Common names
Riverside Sabal Palm

Habitat and Distribution

Riverside, California.
New Zealand. Germinated in the mid-90's. Photo by richnorm.


Known for its enormous, bluish green, fan-shaped fronds and its remarkable cold hardiness, this hybrid from the vicinity of Riverside, California, is also among the fastest growing palmettos. Eventually forming a medium to tall, single-trunked palm, it may have either Sabal bermudana or Sabal domingensis in its lineage.

The gigantic, rounded, evergreen fronds have numerous narrow sword-shaped segments which sometimes droop slightly. The fronds are held on long stout stems ("petioles"). The upper trunk of older specimens is cross-hatched with the angled, wedge-shaped petiole bases of fallen leaves. The petiole bases eventually detach, leaving ring-like scars. Old specimens can become quite tall. A long branching cluster of tiny ivory flowers appears in summer, attracting bees and other pollinators. Small fruits form afterward. Editing by edric.


Grow Riverside palmetto in full sun and fertile, well-drained soil. It does well in hot and dry or cool and damp conditions. It tolerates temperatures of minus 11 C (12 degrees F). Although fast-growing for a Sabal, it is still slower than many palms. Warm soil and summer irrigation may hasten its growth. Use it as an accent plant in a mixed border, or as a specimen in a lawn to bring a tropical look to temperate gardens. It also does well in large containers.

Comments and Curiosities

"Sabal riverside is just a specific stable 'form' of a species of sabal just like blackburniana is. No one has come up with a good analysis as to which one, it just stays true to its form. I purchased both of these from Gary Wood in Fallbrook. My riverside species was way overgrown and quite unhealthy when I got it from his closeout sale. I am not gonna complain, $4 for a 5 gallon rootbound sabal is really a give away. But it's taken a full year to get going. It's picked the middle of Winter to start growing again, now that's a pretty good sign. Note, unlike in the post referred below, I see significant differences even as seedlings between riverside, causiarum, blackburniana and dominguensis. They have totally different growing forms leaf wise and leaf texture wise." (Dr. Axel kratel)

"Here's the original story from Phil, which you can find if you search for 'sabal riverside story' See http://www.palmtalk....abal-riverside/" (Dr. Axel kratel)

"Ed Moore (from San Diego, past President So Cal Chapter IPS) is now about 90 years old. He told me that when he was young, it was almost impossible to get different palm trees. About fifty years ago he visited a private botanical garden (owned by a wealthy individual) and saw this huge blue-green Sabal. He collected seeds and sold several hundred of them. He called them "Sabal-Riverside" at the time and put a tag in each plant. The original plant survived for a while and as I recall the site became a public garden (? Wright Park) for some time but was eventually plowed under. The palm was apparently lost or moved. Ed told me after a decade or two, people just started calling it Sabal Riverside as if it were a species. I've got a huge seeding specimen in my yard. The seeds are about the size of a small marble with the fruit, which is black. It's trunk is thick, the leaves are quite large, but the petioles are not real long; perhaps 6 feet. The photo from RPS above looks like it, but Maxwell's palm is too stretched out in the petioles. I question whether it's the real thing. If I can get around to it, I'll shoot a few photos some day. There's several in Morley Field next to Balboa Park in San Diego. That's where most of the seed brokers get their seeds." (Dr. Axel kratel)

"The theory is that sabal riverside is or was a single tree somewhere in Riverside that is super fast and super hardy (15F and below). It is some sort of sabal hybrid, most likely involving bermudana, but others claim it's of Cuban descent or elsewhere in the Caribbean. I am pretty sure that most sabal riverside being propagated these days are second or third generation offsprings, so if the original tree was a hybrid, how come the offsprings don't change?" (Dr. Axel kratel)

"Nobody really knows, and no one has taken the time to try to get the actual origin documented properly. But I think the hybrid theory is wrong, or else it wouldn't be so consistent from generation to generation. Based on the variety of forms of sabals within single species, this sabal is probably just another form of bermudana or causiarum. It's the same issue with sabal blackburniana, which is thought to be either a different form of palmetto or a different form of dominguensis (I would side with the latter one.)" (Dr. Axel kratel)

"Looking at the size of Riverside and its hardiness, it's probably a form of causiarum. This photo of Riverside is one that impresses me the most, it's taken at Maxwell Stewart's house in Mobile Alabama. From the trunk form, it almost looks like a form of dominguensis." (Dr. Axel kratel)

"Because is it is very difficult to distinguish sabals from one another I suspect there are many misidentified plants and thus subsequent incorrect feedback circulating around. I remember a discussion about S. causiara and S. domingensis being mixed up in an earlier survey of the palms in habitat in the D.R. Later the large paper ligules became the hallmark of causiara but then it was commented that not all populations (P. Rico versus D.R., I think) of causiara have that trait. I think I remember that some at Palomar Community College arboretum were mis-identified. Then there is the difficulty in identifying juvenile sabals with missing labels. Then there are a lots of seeds collected and sold as verified species even though they were harvested from mixed plantings without enough isolation to preclude hybridization. These errors have compounded in the palm collector and nursery realm over the years. In California there seem to be a lot of misidentified sabals and I know of a few nurseries (not palm specialists) that seem to label any sabal as palmetto. In one shipment for example I think there are S. minor 'Louisiana' (which seems more common in CA than regular forms of minor), S. palmetto, S. mexicana, and S. 'Riverside'. And I am just guessing at these IDs and will label them with question marks until they mature." (monkeyranch)

"In conversation I had with Patrick Shaffer he mentioned noticing at least two, if not more, sabals circulating as S. Riverside. Probably the true Riverside, mexicana, bermudana, and dominingensis all masquerading as Riverside. And then I have received contradictorily large and small sized seeds as Riverside seeds in different orders from one vendor. They also sell S. mexicana under the old name S. texana (until I asked them to clarify that this was indeed mexicana) which I suspect has something to do with the mismatched seed sizes." (monkeyranch)

"So, to make a long story longer, I consider many sabal IDs suspect, especially here out west where we don't encounter enough of them (as opposed to Florida) to have a working familiarity and confidence for their labeling." (monkeyranch)

"I wonder if palmtalkers could start a "collection can/fund" to pay for the DNA tests to sort out some of the palm mysteries such as Riverside and blackburniana. How much does a genetic analysis cost? With us all pitching in maybe we could answer some of these questions." (monkeyranch)

"That's not a bad idea, it's not that expensive to do, there are open source DIYS kits you can buy, I've seen it done at Maker's faire," (Dr. Axel kratel)

"I agree with the suspect IDs in the average nurseries here in California. However, because there are only three sabals commonly available in commercial nurseries (riverside, bermudana and minor), the rest of the sabals are considered collector items and are usually available only from reputable collector nurseries where the ID is going to be about as good as you're gonna get anywhere. Because of the relatively common availability of bermudana, the riverside specimen is often thought to at least be a bermudana hybrid or maybe just a hardy form of bermudana, but no one knows. I think you might be right on the sabal minor, a lot of the big ones circulating in common landscape nurseries are too big and fast to be a regular minor, they're most likely Louisiana." (Dr. Axel kratel)

"I got most of my sabals from reputable sources, so I am pretty confident on the IDs of them. Gary Wood has had Don Hodel visit him and set the IDs straight, and Gary Wood is the one who relayed back to me Don Hodel's switch around of causiarum and dominguensis. My sabal riverside came from Gary Wood, and so did my mexicana, dominguensis and blackurniana. I have a sabal minor that is definitely not the Louisiana version, it's too slow and too small to be the Louisiana one. I have not purchased any sabals from the average landscape nurseries. My bermudana and causiarum came from Joe Debrowski, he's one of the most reliable growers, I trust him on the labels. My sabal pumos came from Dwight." (Dr. Axel kratel)

"But this is what makes the sabal genus so exciting! All the subtelties and nuances are intriguing." (Dr. Axel kratel)

"Originally from Cuba, Hybridized palm. All the seeds are from Riverside California. That's how the name come from. The thickest trunk Sabal, it has those boot jack make the trunk looks very ornamental. Love hot sun. Blue green foliage Easy to transplant. perfect for pot as well. (sylvainyang)

Another very cold-hardy Sabal palm, this one hails from Riverside, CA though its parents are not known for certain. Large, glaucous leaves keep their blue-ish color best if grown in full sun but part shade is fine. Can reach 30’ in height, usually more quickly than S. texana. Hardy to at least 15 degrees F.

Many believe this to be the fastest growing of the Sabal palmetto palms grown in southern California. The Riverside is not considered a species and is most likely a hybrid of Sabal Bermudan and/or dominguensis, according to Geoff Stein. This palms looks similar in some ways to a Washingtonia palm, but if you think it’s a Washingtonia at first, you will eventually do a double-take. It is that second glance that makes the Riverside such an in-demand plant among collectors and designers who want an original plant signature as part of their project. As the height-to-spread ratio suggests, mature individuals anchor a solid, even monumental structural stature to a landscape. It’s significant size and stiff, upright crown tell the story. Ellis Farms Riverside Sabals are desert field grown plants. (

"U. A. Young was President of the IPS from 1974 - 76. From 1958 to about 1985 he sprouted and tried to grow whatever palm seed he could get. Obtained from wild, botanical collections, or trade, he wanted to see what would grow in Central Florida, specifically South Tampa. Many palms were lost to freezes or other failures, but he always said it just opened up room for something else. During that time, and as a physician, he was at a medical convention in LA. His companions rented a car for a free day golfing at Pebble Beach. U.A. rented a car and drove to the residential property location along a highway in Riverside where one of his palm friends had located the Sabal. Out of place in California but of unknown origin, he collected seed and grew this palm pictured here. Native Sabal palmetto can be sen in the background." (Brad-Tampa) See photos below.

This is a tillering palm, it exhibits saxophone style root growth (it has a heel), keep top third of heel above soil elevation!

External Links


Phonetic spelling of Latin names by edric.

Special thanks to Geoff Stein, (Palmbob) for his hundreds of photos.

Special thanks to, Dr. John Dransfield, Dr. Bill Baker & team, for their volumes of information and photos.

Glossary of Palm Terms; Based on the glossary in Dransfield, J., N.W. Uhl, C.B. Asmussen-Lange, W.J. Baker, M.M. Harley & C.E. Lewis. 2008. Genera Palmarum - Evolution and Classification of the Palms. Royal Botanic Gardens, Kew. All images copyright of the artists and photographers (see images for credits).

Many Special Thanks to Ed Vaile for his long hours of tireless editing and numerous contributions.

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