The Dry Garden: Stunning flannel bush comes with prickly problems

 

Some years ago, the website of Native Sons Nursery had a photograph of a California flannel bush that had been trained to grow along a garden wall. Each bloom in a spangle of flowers was the size of a teacup. Their yellow could outshine a daffodil, or sunflower. This wasn’t a garden, it was a garden that Matisse dreamed. On seeing that photo, so began years of looking in Los Angeles area gardens for espaliered examples of the glorious genus of natives whose botanical name is Fremontodendron.

And never finding one.

 

It turns out that the photograph, above, was taken in Guernsey by Native Sons co-founder David Fross, who had just left a place that serves alcohol when he saw the glorious display by one of the signature plants of California chaparral growing in one of the Channel Islands between Britain and France. “I’d had two martinis and half a bottle of wine, came around the corner and late evening light was crashing into this yellow door. At first I was staring at the door. Then I focused and said, that’s Fremontodendron.” It ran almost 50 feet along a wall.

As he kept looking, he found that yet more artfully espaliered displays of the plant named for the western pathfinder John C. Fremont were almost invariably in Britain, such as that in his photo at right, taken in London in 1997, or France, or on an island between the two places. The reasons are many, the first being that the British and British adjacent are better gardeners. The second is that the cooler climate has a refining effect on these strapping western plants.

“In England, a Fremontodendron might put on four inches of new growth a year,” explained Bart O’Brien, special projects director of Rancho Santa Ana Botanic Garden in Claremont. “In our area, they can put on six to eight feet in three months in the spring.”

Those, like me, intent on pinning a flannel bush against a wall in its home territory should be warned that Fremontodendrons come armored. While a USDA Forest Service information sheet identifies the leaves as edible by ruminants, they are highly irritating to humans. Under the microscope, tiny hairs look like medieval maces, said O’Brien. “Think of them as having projecting spines in every direction. If you’re doing any maintenance or raking up dead flowers or leaves, do that last and go take a shower and put those clothes into the laundry as soon as possible.” San Marcos Growers advises wearing goggles. Fross said he asks his crews to wear masks when they load the plants on delivery trucks.

 

Another challenge to using this native in Southern California gardens is soil. Fremontodendrons do best in the free-flowing sandy alluvium of the foothills. “In the wild, they often grow on slopes,” said O’Brien. “Rain comes in and flows out.” By summer, the evergreen plants are dormant, in which state summer irrigation swiftly kills them. Death happens faster in clay.

They not only drown, they smother. Mulch should go nowhere near the root crown, where they are highly susceptible to rot. Foothill arborist Rebecca Latta said the soil line should sit just where the top roots meet the main stem.

Although now is the time to admire their flower, the best time to plant a Fremontodendron is late autumn. “Generally speaking, we plant them in the fall, water them in, and then we’ll only water them the same year they’re planted if they need it and hardly ever again,” said O’Brien. “Most that make it through that first summer are perfectly fine forever after.”

Breeding our native flannel bush with the South American Fremontodendron mexicanum to produce plants better adapted to life near sprinklers, drip lines and hoses has led to hybrids such as California Glory, Pacific Sunset and San Gabriel. All are slightly more tolerant of water than F. californicum, said O’Brien, but not much.

However a much more water-tolerant hybrid is in the works. This cross, between Fremontodendron californicum and the tropical Monkey’s Hand Tree (or Chiranthodendron pentadactylon) is being propagated for eventual release into the trade at Rancho Santa Ana.

First accomplished a quarter-century ago by (then) Rancho graduate student Austin Griffiths, the hybrid produced a stunning improvement. While Fremontodendron californicum’s nectar value is minimal, the cross has sunward-raised flowers that fill up with rain, attracting not only hummers but all manner of birds to drink. Curious, Fross once tasted water from the blossom. “It tasted like nectar of the gods.”

Smaller Fremontodendron selections recommended by Fross and O’Brien include Ken Taylor and El Dorado Gold. Fross likes Butano Ridge for its striking red stems.

All Fremontodendrons have long, stunning flowering periods. How early they start and late they last depends on location and weather. Foothill specimens are flowering now, and coastal ones should be following. “Cool weather makes them last a lot longer,” said O’Brien.

Though he and Fross are old friends and with Santa Barbara horticulturist Carol Bornstein are coauthors of “California Native Plants for the Garden,” O’Brien doesn’t think this native can be given its most stunning treatment on home ground. If it grows at all in our gardens, it grows too fast to be espaliered. Then there are those irritating leaves.

However, having wandered tipsily around that corner in Guernsey and being stunned by what he saw, years later and stone-cold sober, Fross still believes we can trim and pin the plant to artful effect here, at least in cooler coastal areas.

Watch that space.

-- Emily Green

The first and fourth photos show a Rancho Santa Ana Botanic Garden cross between the California flannel bush (Fremontodendron californicum) and the tropical monkey’s hand tree (Chiranthodendron pentadactylon). The bottom two photos show a newly planted garden Fremontodendron 'San Gabriel,' a hybrid of F. californicum and F. mexicanum introduced by Rancho Santa Ana Botanic Garden.

Photos of flowers by Emily Green

 

Comments

[Sherri Akers]

I have a Fremontodendron in my garden and can't imagine trying to 'train' one! I feel that mine trained me - objecting to most locations and completely rejecting the idea of being in a pot - she told me exactly where she wanted to be and flourished there - as tall as a tree now! I lost 3 and so the one that flourished is a treasure.

[Dan Songster]

Emily,
Such a great article about one of my favorite natives for cheerful spring color. Yes, the stellate hairs are an issue in maintenance but once you have been irritated by them you are unlikely to forget to use gloves!
I plant the larger forms like 'Pacific Sunset' and 'California Glory' and expect 3-5 years of rampant growth and spring flowering. Secretly i hope for a year or two more and sometimes get it, but in clay soils it can be tough for this plant especially as you mention, if it receives any summer water.
I remember years ago when Santa Barbara Botanic Garden had one espaliered on each side of their library doors, they looked pretty good for a number of years, likely due to the cooler temps up there.

[Barbara Eisenstein]

My all time favorite flannel bush is West Hills Hybrid, reddish stems, deeper orange on back of sepals (yellow flowers are sepals, not petals), leaves odd green with warm hints. I have Calif. Glory in my backyard - got them for volunteering at a plant sale or I probably wouldn't have had the courage to plant them. One died last summer, other 2 are beautiful. I always cover up & wear a face mask when doing anything with this plant.

[Barbara Eisenstein]

My all time favorite flannel bush is West Hills Hybrid, reddish stems, deeper orange on back of sepals (yellow flowers are sepals, not petals), leaves odd green with warm hints. I have Calif. Glory in my backyard - got them for volunteering at a plant sale or I probably wouldn't have had the courage to plant them. One died last summer, other 2 are beautiful. I always cover up & wear a face mask when doing anything with this plant.

[Polly Hodges]

Can you tell us what she likes so much about her special spot?

[Polly Hodges]

Can you tell us what she likes so much about her special spot?

[Melly office plants]

Cool post.
I learned something new today.

Thanks.

[Ian Barclay]

Coming from the Northwest I feel qualified to comment on their behavior in cool climates.

I suspect the espalier trend for Fremontodendron is largely cultural. The British figured out that was a successful way to grow it for them, so that's what they do.

Rampant growth is possible here as well - mine have grown several feet a year. Only when they get older do they slow down, assuming they are happy enough to continue living.

They can even grow here in the Northwest on heavy clay and do fine as long as they are allowed to go completely dry for a couple months in summer. Soil isn't the problem, just irrigation.

This might not be so important for Californians but it seems like it ought to be possible to breed Fremontodendrons that are both cold hardier and adaptable outside of the west. Many of the hybrids could be back-crossed with cold collections of F. californicum or from the form found in central AZ which is adapted to heavy summer rainfall. It's great that people are still working with Fremontodendron anyways; I look forward to experimenting with some of the newer hybrids. Throwing Chiranthodendron into the mix seems to detract from frost hardiness. I tried x Chiranthofremontia lenzii once and it seemed the least cold hardy of the any of them. Would be fun to cross this with F. decumbens.

Barbara - would love to know what the parentage is for Western Hills Hybrid, if you know more about it. It sounds cool!

I had thought Fremontodendron mexicamum is from Mexico, not South America.

[Rebecca Latta]

Great article. It looks amazing with the darker blue Ceanothus species. I like 'Ken Taylor', but would like to try the West Hills Hybrid in my garden. I still remember my mom taking us to Rancho Santa Ana Botanic Gardens when we were little to see the Fremontodendron in bloom!