Romneya Species, Coulter's Matilija Poppy, California Tree Poppy

Romneya coulteri

Family: Papaveraceae (pa-pav-er-AY-see-ee) (Info)
Genus: Romneya (ROM-nee-uh) (Info)
Species: coulteri (kol-TER-ee-eye) (Info)



Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Full Sun




Foliage Color:



4-6 ft. (1.2-1.8 m)


4-6 ft. (1.2-1.8 m)


USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Where to Grow:

Unknown - Tell us



Bloom Color:

White/Near White

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall

Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

7.9 to 8.5 (alkaline)

Patent Information:


Propagation Methods:

By dividing the rootball

From seed; direct sow outdoors in fall

Seed Collecting:

Bag seedheads to capture ripening seed

Allow pods to dry on plant; break open to collect seeds


This plant is said to grow outdoors in the following regions:

Agoura Hills, California

Alamo, California

Amesti, California

Arroyo Grande, California

Berkeley, California(2 reports)

Big Sur, California

Boulder Creek, California(2 reports)

Brentwood, California

COARSEGOLD, California

Calistoga, California

Cameron Park, California

Castro Valley, California

Citrus, California

Clayton, California

Corralitos, California

Davis, California

El Cajon, California

Elkhorn, California

Fairfield, California

Fallbrook, California(5 reports)

Felton, California

Ferndale, California

Fontana, California

Fresno, California

Interlaken, California

Knights Landing, California

Larkfield-Wikiup, California

Livermore, California

Martinez, California

Mendocino, California

Mill Valley, California

Monterey, California

NORTH FORK, California

Nevada City, California

Nipomo, California

Oak View, California(2 reports)

Ojai, California

Pajaro, California

Rohnert Park, California

Sacramento, California(3 reports)

Salinas, California

San Diego, California(3 reports)

San Gabriel, California

San Leandro, California

Santa Barbara, California

Santa Paula, California

Sebastopol, California

Shingle Springs, California

Spring Valley, California

Vista, California(9 reports)

Walnut Creek, California

Watsonville, California

Whittier, California

Yosemite Lakes, California

Littleton, Colorado

Pahrump, Nevada

Oregon City, Oregon

Portland, Oregon


Woodruff, South Carolina

Austin, Texas

Marysville, Washington

SEABECK, Washington

Seattle, Washington(2 reports)

Sequim, Washington

Silverdale, Washington

show all

Gardeners' Notes:


On May 19, 2019, oldwesternlady from Whittier, CA wrote:

I overwatered mine and it is gigantic. It is on the south facing side of the house in zone 10. Cutting it back as soon as bloom is finished. It is so well established I suspect I could never get it out, so cutting back is my only option. It is at about 10 or more feet, and very, very thick. Blooming now.


On Nov 20, 2016, pb1234 from Mill Valley, CA wrote:

Love this plant. It is spectacular in bloom. When it is not in bloom the foliage is handsome -a kind of blue/grey/green color. I have never propagated this as I have heard its rather difficult -but I buy it in one gallon containers. It may not look all that great in the container, but it will produce new growth after planting.The trick is to be very careful in not disturbing the roots when planting. This plant is best placed somewhere where it can spread and get tall. Full sun and well drained soil is best, not too much water. Having said that, I have been successful planting this where there was some dappled shade with clay soil loosened and amended with grit. Should be more widely planted for dry gardens.


On Jul 20, 2016, gregardener from Littleton, CO wrote:

Romneya coulteri grows on my north, east-facing slope in nearly full sun all-day. It blooms in June-July here. I was devastated when an underground utility line had to be replaced and reburied last year fearing that the trenching machine would do it in. Unfounded fear. The original plant and its offshoot rebounded well. More flowers this year than ever. Tried transplanting the offshoot restock which did not succeed.


On Apr 3, 2016, whyiplay from San Diego, CA wrote:

It's April 3, 2016 in San Diego, Ca and my matilija poppy plant is full of buds and 3 of them are fully opened. This is my 3rd or 4th attempt to grow this plant. I have no sun in my backyard so I planted the poppy right smack in the middle of my front yard, in between my aloe, pencil cactus, and tomato plants. I did add some gravel and sand to the existing soil back in the Spring of 2015. I held back on the watering during the summer months, but the plant looked awful. My roommate insisted I water more often, even in winter since we have not had a great rainy season. I was afraid I would kill the plant; but now it seems to be thriving and is at least 5 feet tall. Have had a great time growing this poppy plant and I hope to learn how to cross-pollinate with a bit of help and information fro... read more


On Jul 12, 2015, mfranke from Cameron Park, CA wrote:

I've just moved to Shingle Springs, CA and have a stand of Matilija Poppy growing - with no water - on a hillside - in drought season. They bloomed like crazy over the Summer. They are done blooming now. I'd like to try propagating with the seed method - but a have a few questions about when and how to do it?

1) When do I collect the seeds?
2) Do I need to store them in a dry place and wait until Fall to plant them?
3) I've heard about the need for smoke. I've also read you can soak them in 'rubbing alcohol for about 15 minutes to help weaken the seed coat (scarification) and speed up germination' ( read more


On Jul 23, 2014, royfotograf from Grants Pass, OR wrote:

This plant also found on campus of Sonoma State Univ.,
Rohnert Park, CA.,
edge of parking lot at Native Plant Garden. A real joy for
photographing up close.


On Jul 15, 2014, queenofhotpink from Sequim, WA wrote:

We love this plant - it just suddenly appeared in our yard. There is one plant growing wild about a mile from us. We do nothing with it and it just produces beautiful flowers but it was a challenge finding out what it is - even the local professionals were unsure. Our climate is fairly dry, with summer fog blowing in and out, we are right on the Strait of Juan de Fuca so there is significant wind often. The soil is glacial deposits but our Matilija appeared in a raised bed. It has a very delicate scent that teases rather than overwhelms. We have Angels Fishing Rod propagating around the yard and now the Matilija and they just really dress things up this time of year. Neither of these plants require watering and the deer don't eat them. I didn't cut it back last year but maybe this fall I w... read more


On Feb 22, 2014, greenthumb83629 from Woodruff, SC wrote:

Got these seeds from smart seeds, about 30, only planted 4 to see how they do. just used cheap garden soil from lowes , about $1.98 a bag, put 4 in small tin, just put seeds on top of soil then sprinkled tiny bit of soil on top, then put dry oak leaves on top , set them on fire and let them smolder about 5 min then soaked them with water, had cold weather here in south, kept them in house about 1 week then set tin outside in sunny location on a plant stand, out side about 1 week well today I see 3 little heads sticking up and its February, its so rewarding.


On Feb 9, 2013, copperfirefly from Rayleigh,
United Kingdom wrote:

My friend has this poppy in her garden and it is lovely,we live in England and she has never seen another one sold at any garden centre over here,and believe me she has been to many,my friend is moving in two weeks and does not want to leave this plant behind,so it has been dug up and I am keeping it a my place until she can sort out new garden,so when she has it back part of it is staying with me,I am thrill .
From Rayleigh,Essex.England.


On Oct 1, 2012, RosinaBloom from Waihi,
New Zealand (Zone 1) wrote:

Romneya coulteri 'White Cloud' is a subshrub grown for its strikingly large, white poppy-like flowers which have crinkled petals, and a conspicuous centre boss of golden yellow stamens. They bloom over a long period of summer.
Their underground systems can spread vigorously - even travelling under a concrete driveway - according to my neighbour who has them growing in her garden. The old shoots can be cut back to the ground in spring.
They are a native to California and New Mexico.


On Sep 30, 2011, LadyPuffin from SEABECK, WA wrote:

Both my mother and I have had good luck with growing Matilija Poppys. We were able to take cuttings with us when we moved from Gig Harbor Wa to Seabeck WA. The plants adapted quickly to the new soil. Mine had no admendments and my mothers a little. She waters a bit better than I do, but both groups of plants have done well. They even survived a sudden freeze (dropped into low teens in less than 5 hours with harsh north wind last Nov 2010) They do spread quickly. I have one plant that came up from a runner, thanks to my husband removing the mother plant due to its invasivness. I am going to try and start some seed this year and hopefully have baby plants. We are planning on a major move to Texas, and I do not want to leave this star behind.


On Jun 19, 2010, srkrause from Boulder Creek, CA (Zone 9a) wrote:

Do not over water. If you do it is less likely to bloom very much!


On May 18, 2010, gonnagrowit from Coarsegold, CA wrote:

I've enjoyed this beautiful plant in all it's natural glory when visiting the El Portal canyon that runs along side the Merced River below Yosemite National Park. A very hot and dry environment in the summer. I recently purchased a 5 gallon at a nearby nursery. It's in the ground now and is looking a little wilted but it has buds that are ready to pop. Fingers crossed.


On May 17, 2010, chemosabe from Berkeley, CA wrote:

there are several wild stands of these in the local east bay hills here. late last november, just before the rains started, i bare rooted 3 plants out of the dry dusty soil and trimmed them down to the base. i planted the 8-12 inch roots in pots a few days later and kept them out in the winter. two of them sprouted new growth within 2 months and the third took longer, but ultimately did better. i believe i (over) fertilized them hoping to spur them on. i also had a little chip of root left over, about an inch long, and planted it as well, just below the surface. this one actually has done the best, now about 1 foot tall and looking healthy. two of the others have had leaves turn brown and fizzle a bit but one looks decent enough. will keep them all till next year to see if they do... read more


On May 11, 2009, anelson77 from Seattle, WA wrote:

I have this growing in a tough out of the way spot in near full sun. It blooms for a long time in early summer with huge papery looking white flowers with fluffy yellow centers. It is large, will take over a small space, and will look ratty in the fall, but If you have the space and sun I would recommend it for Seattle.


On Jun 16, 2006, daylillydawn from Felton, CA wrote:

I planted this tree poppy in my Felton, CA yard 2 years ago and it is now 8 feet tall and 3 feet wide, and spreading more each year. I could not be more thrilled! It is my favorite plant and it is loaded with flower buds about to explode!! The most important thing when you plant this shrub is to make sure it has PERFECT drainage and LOTS of sun!! Plus don't overwater it.


On Jun 16, 2006, MaHubs from Santa Rosa, CA wrote:

I have not yet planted this but I intend to soon. I see many of them growing in my neighborhood (Santa Rosa, California) and even on the sides of Highway 12, which I am sure they receive little/no water. I have a friend who's grown them in Portola Valley, California also. And I know they grow outside the supermarket right next to the ocean in Gualala, California. Again, I'm sure they get no water there and there's NO rain in the summer, just some fog.


On Jun 9, 2006, madyaas from Marina, CA wrote:

This plant is getting to be fairly common around Monterey. I've seen it growing along the recreation trail in Monterey, at CSU Monterey Bay, and in the city of Marina.

The soil in each place tends to be pure sand, exposed to wind, and sun, and the plants don't receive any other care. If happy, they'll spread like monsters and grow very tall.

I bought several at Valley Hills Nursery in Carmel Valley a month ago. Mine haven't spread out yet, but they've definitely grown taller, and all of them have small flower buds developing. This is a gorgeous plant and if you have the right soil, snatch them up.


On May 15, 2006, irishgardener from Dalkey, County Dublin,
Ireland wrote:

I found this plant growing under my wall from a neighbour's garden and after many failures got a root cutting to grow: it's the pride of my garden, two metres high and covered in those beautiful white crushed paper petals in summer. I could never get it to grow from seed, but I'll certainly try the tips I've read here.

For the record, Dublin is definitely not as warm (or dry, I suspect!) as California, but my Romneya certainly likes the climate here. It's rare here, though, I've only seen it in one other garden and even our Botanical Gardens in Dublin seems to be unsure where their plant is.


On May 1, 2006, gooley from Hawthorne, FL (Zone 8b) wrote:

I have seeds. I have gotten seeds to germinate in the past (but I later killed the seedlings due to carelessness) by soaking them for a few hours in unleaded gasoline, removing them and letting them dry, then sowing them. The soak in a solvent removes the wax that prevents germination. I'm about to try again.

It sounds bizarre but various people have assured me that this works, and my experience squares with that. Not sure how well the plant will do here in north Florida: I had a potted one sent by mail and it didn't last long...overwatering? It didn't look in the best of health when it got here.


On Jul 18, 2005, wvanbusk from Oregon City, OR (Zone 7a) wrote:

Have always liked the appearance of this wonderful flower.

SIZE: The plant is rather large and has a tendency to sprawl and produce tall stems (up to 9 feet tall) that may fall over. Spreads gradually by finger thick and fragile rizomes. I have this Planted in Fort Bragg, California, in transistional sandy soil, from a potted specimen. Have seen this in several locations around Southeast Portland, OR where I collect seeds.

CULTURE: Difficult, but possible, to culture by root cuttings; personally I have had no success in two attempts), but the SEEDS are ONLY likey to germinate in media treated with SMOKE. Nitrite from combustion products has been identified as the primary germination trigger; not heat or ash. Smoke treatment of sand or use of charcoal among ... read more


On May 15, 2005, RobertCA from Valencia, CA wrote:

I first saw the Matilija Poppy in a Botanical Garden in Claremont California. Right away I fell in love with it. After having the sales girl in the gift shop print out some information for me on the flower I right away stopped by my local nursery in Santa Clarita and purchased a 5-gallon plant. It has numerous buds on it. However, I didn't realise until i got home that I closed the car door on one of the branches and broke one of the branches just below the poppy buds. I cut the branch just below the break to clean it up a bit.


On Nov 19, 2004, pforrester from Fallbrook, CA wrote:

I bought a 1-gallon, three inch plant in north San Diego County, at Las Pilatas. After 30 gallons of water at planting and two and a half weeks it has two new leaves. I also soaked 100 seeds the same day. I soaked the seeds for 24 hours. I gathered dead Christmas tree branches and dried oak tree leaves. I placed ordinary California soil on a fine, wire mesh, flat, bacon grease spatter stopper. In my fireplace I started a fire with the leaves and added pine branches. When fire died down to smolder I held the the soil over the smoke for 15 minutes. I added leaves and branches as needed to keep fire going but only smoked over a low, smoldering fire. When soil had cooled I placed a coffee filter on the soil and placed the seeds on top. I covered with another coffee filter and sprinkled smoked... read more

Update May 21, 2006

I was able to transplant one seedling into the garden. It was doing well until my "gardener" hit it with Roundup. :( Matillaja Poppy from a pot is healthy and spreading. It is 4-5 feet wide now. I have tried to propagate from suckers two times last winter--no luck. I am going to try the seeds again but this time I sprinkled them on damp soil in a big pot. Smoked some potting soil as I did 1 1/2 years ago. Covered the seeds with smoked soil, watered and covered in plastic. Set outside. I should know in 3 weeks if they have germinated.
Update June 13, 2006

It has been three weeks and it looks like I have about 20 out of 100 seedlings so far. When the seedlings started poking out of the soil I took off the covering let them get a little sun each day. Moistened top of soil lightly to prevent the seeds from drying out but not much b/c overwatering kills them.


On Oct 13, 2004, Kelli from L.A. (Canoga Park), CA (Zone 10a) wrote:

According to what I was told, this plant is native to two relatively small disjunct areas in the U.S. - in Ventura County, CA near Ojai, and in Riverside County, CA. In the wild, the seeds will only germinate after a fire, though the plant spreads freely from runners. There are a couple stands that where planted at what is now Malibu Creek State Park and they are very popular flowers with park visitors.

The smell of the flower is rather strange, kind of like rotten fruit.

I have never tried growing this plant at home. I have read that it is too invasive for the average home garden.


On Aug 16, 2004, Opoetree from Oak View, CA wrote:

When I looked up "Matilija Poppy" I thought I'd find a few notes from the Ojai Valley. We have many of these poppies growing wild around here -- but maybe they are a little map calls them Romneya trichocalyx -- not coulteri. The pictures look the same, though. We have a creek called "Matilija", as well as a canyon, and other areas too. I have some growing in my yard on a little hill, and they have spread out nicely. They are beautiful flowers and not hard to take care of.


On Jul 21, 2004, zelda223 from Ashland, OR wrote:

Thrilled to report this plant is growing happily in various locations in Ashland, OR, zone 7. Hard to get it to thrive from runners...7 out of 10 dug up in the fall and potted failed to make it. I have been told by gardeners on the Oregon Coast not to disturb the potted cuttings for 5-6 years! It's not available at local nurseries so I will continue to experiment.
First saw the Matilija Poppy 35 years ago in Mendocino California near the Art Center. It was a mature specimen and it took my breath away.


On Jul 9, 2004, WalterT from San Diego, CA (Zone 10a) wrote:

The Matilija Poppy (Romneya) is known by that name and its flowers are white.

The California Tree or Bush Poppy (Dendromecon) blossoms are yellow. The California State flower is Eschscholtzia (not a typo) californica, with three varieties, one of which has three types - talk about hair splitting! It is a relatively small plant with yellow to orange flowers.

In San Diego county alone there are 7 species of Eschscholtzia. (Info from Beauchamp's A Flora of San Diego County.)


On Jul 8, 2004, hanna1 from Castro Valley, CA (Zone 9a) wrote:

Oh, do I love this poppy, first saw it growing in Berkeley, Ca, and went nuts. I found out how well it grew in Santa Barbara, Ca., so my husband and I went to the Botanical Garden sale there. They were all out, and I was so sad. I just bought my very first here, We have a great nursery who will always do special order and it only cost me $17 for 2 1gallon plants. One branch is laying flat, and is sending up new branches from its nodes, it looks like I will have a few flowers this season, and I can't wait. I realize how large it can get, but it can be transplanted via cuttings according to the Horticulture lab at UC Berkeley, one lady said she had them all over her yard. The burning of seeds should work well, I could'nt do that where I lived in Southern Ca in Chino Hills, I could of started... read more


On Jun 24, 2004, marymalarky from Qualicum Beach,
Canada wrote:

We just moved to an established garden on Vancouver Island, near the sea. We have a large specimen, about 6' tall and 5' around. It just began blooming (mid-June). The nursery owner in town says it is rare here and that it would be hard to replace. I need to move it, but will try to take the babies into pots first, to see if they survive, before I try to move the mother. It seems to do well in our mild, wet winter, dry summer climate that we've had this year, with no extra water after March.


On May 1, 2004, gardenfiend2 from Vallejo, CA wrote:

To the best of my knowledge, the common name for Romneya is the Matilija poppy.


On Oct 1, 2002, spotcat wrote:

Plant suckers easily, can be very invasive. Reduce water in summer to limit suckers. Dig up rooted suckers to get more plants. or take a thick root cutting and try that. Seed difficult to start. In fall, make seeds germinate by mixing them with damp potting soil in non-flammable flat(or line flat with strong foil), burn pine needles on top of flat for 1/2 hour, then water flat and maybe they will sprout. Really, not a joke.