Iris x pacifica: Hybrids & Jewels of the West Coast

PCH Native Warrior w: Stachys Primrose Heron DSCN2479

Iris x pacifica ‘Native Warrior’ next to Stachys byzantina ‘Primrose Heron’  These Iris are very garden worthy and can combine beautifully with plants  with similar cultural requirements

(I wrote this several years ago for the HPSO Bulletin, when it was actually printed on paper, and thought re-issuing it today, edited and expanded, might be helpful to some as we are about to enter their flowering season.  The iris pictured on my Blog’s masthead is Iris x pacifica ‘Simply Wild’ poking out from the base of the Chilean shrub Fabiana imbricata ‘Violacea’)

Gardening is no more or less subject to the vagaries of fad and fashion than the other activities we dabble in.  Marketers prey on us luring us with plants possessing new and alluring characteristics, promises of larger flowers, more disease resistant, floriferous, more exotic or environmentally responsible, less maintenance intensive… the list goes on.  Gardening is a very personal endeavor and as such we will always be subject to such Siren calls.  There will be the righteous amongst us convinced of their own focused vision who seem to be immune (but what, we might ask, are they missing?) and there will be those who simply surrender completely to the beauty and bounty around them making themselves easy prey.  In the long run, who is to say who is right?   Our knowledge is imperfect and we are weak…. The act of gardening strengthens us, provides us with the opportunity to learn and in so doing puts us into relationship with the living world around us.  We become better gardeners capable of making better, though still imperfect, decisions.  Whether we garden to augment our own diets with what we grow or are trying our hand at healing a small piece of a damaged earth, or building a place of respite for ourselves and friends or trying to model ‘right’ behavior for our children and neighbors, we are out in our gardens and landscapes learning something of how incredibly complex this earth is…and that is all good.


Iris x pacifica ‘Survivor’s Son’ bloomed heavily in May of ’15 growing shaded beneath a Chinese Windmill Palm along my parking strip. The flowers are smaller than many hybrids, but are very numerous.

Genus Iris has not escaped the focused intentions of hybridizers, teasing botanical performances from their charges that can be found no where in nature.  Whole catalogs extoll the virtues of Border, Short, Mid and Tall Bearded, Japanese, Siberian, Louisiana, Spuria and various other such ‘creatures’ all flaunting combinations and extremes of color and unique or oversized floral structures, often exotic and flamboyant!  Within this world of Iris is a series that we really should pay attention to, the species and subspecies native to the western coast of North America, the Iris series californicae (There are 16 other series within genus Iris that are comprised of species sharing DNA and, with it, a particular history of development and the physical characteristics that go along with it.).  Several of these have overlapping ranges and, where this occurs, it is possible to find hybrids.  These are precocious plants and if hybridizers needed any encouragement in pursuing these, this would seal the deal.  If you look you would soon discover that there is a committed following to these iris and their hybrids.  The hybridizers have been busy over the years, though their production has been on a more regional scale and while they are generally not of the same physical stature of their many hybrid cousins, the x pacificas are supremely well suited jewels for our gardens.

I am a horticulturist and gardener.  Like you, I try to do the best I can with the resources available.  When I was still a gardener working in Parks my imperatives were threefold: to do so responsibly given my sites, budget and public need; second, that my work be ‘beautiful’ especially given that in austere times beauty is often sacrificed leaving utility alone which is insufficient; and third, that my work be educational in itself to help ‘wake’ people up to the possibilities we have as residents of a truly incredible region.

'Survivor's Son', very robust and floriferous.

‘Wild Survivor’, very robust and floriferous.

When I choose plants, I try, but it’s difficult, to keep in mind their places of origin.  Right plant.  Right place.  This is absolutely vital when trying to produce a xeric low water use landscape.  Sometimes I draw from a long list of what I call ‘West Coasties’ which includes not only our native Valley flora but much from southern Oregon and California flora as well.  Other times I expand that list to include the other mediterranean regions of the world which occur on the west coasts of the continents at roughly the same latitude north or south.  I love pretty.  And I find that very often by choosing plants that come from similar regions and niches, that have been ‘shaped’ by like conditions, they ‘play well together’.

To do this takes time spent gardening in one place while at the same time looking to other areas that share similar conditions.  You begin to make connections.   It is a learning process and it is based on what nature herself has done over millennia.  We have to ask ourselves where, in a broad and deep sense, do we garden?  Then can we make wise choices that can serve several purposes.


Iris spp. in bloom on a ridge top in California’s Armstrong Redwoods State Natural Reserve

We live in the Holarctic Floristic Kingdom, the largest by far of the six such world Kingdoms.  Each Kingdom is distinct and can be mapped out on the ground.  Each contains a shared flora that can be used to define it.  The Holarctic includes roughly all the northern latitudes north of the Tropic of Cancer at 23.5deg.  up to the north pole.  This was not an arbitrary decision while made puzzling over a map.  It contains a number of plant families and Genus, like the species Iris, that are endemic, or occur in none of the other Kingdoms.  To walk the lands of one’s Kingdom would lead to a botanical familiarity that is ‘comforting’.  This is not to say that you wouldn’t come across plants that were unknown to you.  Kingdoms are defined broadly.

More usefully, we live within the Rocky Mountain Floristic Region, which includes everything west of the Great Plains to the Pacific and from the San Francisco Bay area north to Kodiak Island Alaska, excluding the Great Basin and much of the interior Canadian portion.  Regions have a higher degree of species consistency that would be reflected in the plant populations within its various types of landscape, forests, woodlands, savannah, meadow, riparian, marsh or open water areas.  Our region contains the greatest diversity of conifers in the world.  It too has many endemic genera including Sidalcea,  Tellimia, Tolemia and Vancouveria.  Other genera like the Castellja, the Paintbrushes, have their major center of diversity here.


Iris x pacifica ‘Pacific Rim’ with very delicate flowers, a smaller and less robust hybrid growing in a drier and shadier part of my parking strip.

The Vancouver Floristic Province lies within this Region between the Pacific and the Cascades while the California Floristic Province lies to its south divided by an ill defined border.  Such plant species and genera as Sequoia sempervirens, Sequoiadendron giganteum, Darlingtonia californica, Vancouveria and Whipplea are endemic to it.  Also resident here are the Californicae series of Iris, sometimes referred to as the Pacificas.  These too are endemic and they are little jewels.  While all Iris species (there are 260) are northern temperate residents, members of the Holarctic, Iris californicae have narrow and precise requirements that limit them to the mediterranean west coast of North America.  Beardless, (Iris flower structure) these species all share wiry rhizomes and roots and have long, narrow, mostly evergreen leaves that present a ‘grassy’ effect when compared to the broader blades and fans of many others.  The entire structure is fiberous the leaves persistent.  All are low in stature relative to other species.  Iris tenuis and Iris missouriensis occur here as well, but they are not part of this particular series likely sharing more of their history with other Iris than with these.  These Iris deserve a place in every West Coast garden.

Pacificas, having originated here, are uniquely suited to our region.  Gardeners in other parts of the country must take extraordinary measures to get these to perform or simply survive.  Other places are too hot or wet in summer and too cold in winter, sometimes a combination of all three.  While I’ve heard of others having trouble with these here I never have.  I don’t know what might be wrong with their site conditions.  Most of the species can be found in California with fewer native in Oregon generally occurring in open woodlands and along forest edges.  By the time you move to the Puget Sound area even Iris tenax becomes rare.  Temperature is a factor.

Iris PCH Big Money DSCN0671

Iris x pacifica ‘Big Money’

Growers have also found that heavy wet soils can be their death.  Pay attention to drainage.  They seem to thrive in open coniferous forest (remember that evergreens suck up water year round).  Alternatively plant them on slopes where they will get surface runoff or mix in pumice or 1/4-10 gravel.  Give them some sun for best bloom, but avoid the baking afternoon sun for most of these.

Iris dougalasiana is a coastal species.  Prior to our interference you rarely saw it out of sight of ocean.  It is evergreen and vigorous, but not as tolerant of the drier and warmer conditions inland.  Keep this in mind when you site it.  It is beautiful.  I have planted it at the top of the bank in a few places along South Waterfront and more recently at Riverplace Esplanade.  It gets afternoon shade so it is not so severely tested.

PCH Pacific Snowflake DSCN2439

Iris x pacifica ‘Pacific Snowflake’ an Aitken hybrid

This species is a common component of many of several hundred named hybrid cultivars.  The species is larger than most in the series, it is fully evergreen and is a robust clumper.  These characteristics have proven desirable amongst hybridizers.  ‘Canyon Snow’, is a white form, others range from light blue-violet to dark purple; occasionally white, rarely yellow.  Many of its cultivars have been crossed with other more interior species and have been proven to be much more tolerant of inland conditions.  One, Montara, exhibits a very different color palette with its gorgeous russets and golds and evergreen foliage.  Montara Mountain, its namesake, is at the south end of the San Francisco peninsula and is home to a large native stand of I. douglasiana.  This plant has done reasonably well for me on a south facing parking strip which would have been a poor spot for the species. It received some protection from heat and sun by its neighbors but began to decline more as a result of root competition with its neighbors compelling me to move it to a more easterly location where it has thrived.

Iris PCH Simply Wild DSCN0641

Iris x pacifica ‘Simply Wild’ floating above Geranium ‘Lawerence Flatman’

One of the most prolific hybridizers of I x pacifica has been Joseph Ghio who began as a teenager in ’54 and is still working with over 350 named hybrids…this doesn’t count the Beardeds and other Iris he works with.  I’m including a listing of his hybrids here.   Each listing includes a link to a photo and includes information on parentage for those of you interested.  Most of these have to be sought out.  Others have produced hybrids as well including Terry Aitken, the owner of Aitken’s Salmon Creek Nursery, just north of Vancouver, WA, who is still producing and selling Iris other than the Pacificas.  Hybridizing has been occurring for a long enough period that many hybridizers rely on early hybrids for parent material rather than using original species stock.  There may still be reason to go back to the ‘source’ as several species have characteristics that may not be ‘represented’ in the gene pool now popularly being utilized.  Several have distinct populations in their natural range with variation in flower and form of the plant.  Our own Iris tenax, the predominant representative in Oregon into southern Washington, is sometimes known as the ‘rainbow Iris’ due to its many color forms. Perhaps as the West Coast gardening public becomes more aware of their value and adaptability more of these will be brought back into production.  In the mean time a visit to Ghio’s Bay View Gardens nursery should be on everyone’s list when in the Santa Cruz area.  Ghio is a great example of what persistence, passion and attention to detail can produce when working with a species with such potential.   (Here’s a link to a picture site with dozens of varieties.)

There are two caveats when working with Pacificas: first, because they are adapted to our summer dry conditions and go dormant then…leave them alone!  Unlike many other plants you don’t want to ‘mess’ with these during their summer dormancy.  This is contrary to many herbaceous perennials which you divide during their Fall dormancy and even some other Iris, that are commonly divided in summer after blooming…,  but not these.  Do not disturb!  Should I say it again?  Wait until the fall or spring rains come and root growth initiates.  This is important.  Dig your plants for division after the rains begin.  Then pot up your divisions and protect them.  This brings us to the second, young plants in pots are not as cold hardy as your established clumps.  Protect them or risk losing all of them, this is a major production problem locally if the grower is unable to protect their pots during our sudden cold snaps.  Protect your new plantings in the ground with a mulch.  Then leave them for a few years before you divide again.  The rhizomes of Iris x pacificas grow at the soil surface and are vulnerable to cold damage especially if they are newly planted out.  Also, don’t bury them in the soil when you plant to ‘protect’ them from the cold!

Iris PCH Drives You Wild DSCN0677

Iris x pacifica ‘Drives You Wild’

On one of my old downtown sites, Friendship Circle, at the west end of the Steel Bridge,  I had planted a mixture of the hybrids, ‘Simply Wild’, ‘Drives you Wild’ and ‘Native Warrior’, all three are evergreen with varying amounts of velvety red, burgundy and darker, with gold and or cream.  All three are Ghio hybrids and Mitchell Award winners.  Unfortunately Yellow Nutsedge got started in the bed.  One summer I left its care to a mostly unmonitored seasonal worker who failed to see the Nutsedge.  By the time I discovered it the Nutsedge was flowering and I spent several hours, late in the summer, trying to extract it.  I should have waited until Fall, dug the entire area and separated out the Iris from the then ubiquitous Nutsedge and its nutlets, or simply tossed it all and started over, but I didn’t.  I lost most of the Iris to root disturbance in the process…and the Nutsedge remained.

PCH Tranus DSCN2455

Iris x pacifica ‘Tranus’ a smaller more compact form

At South Waterfront Garden, next to Montgomery Circle is a triangular bed full of ‘Simply Wild’.  Elsewhere in the garden can be found ‘Blue Moment’, ‘Sea Admiral’ and ‘Drives You Wild’.  Along the esplanade is Iris tenax ‘Oregon Waterfall’ and further south toward the Marquam Bridge is more Iris douglasiana as well as I. x pacifica ‘Big Money’.

One of the first Pacificas, ‘Native Warrior’, that I planted in Parks is on the corner of Main and 4th under some Elms.  It’s a little too shady but they bloom well enough.  They receive regular summer irrigation but the Elms draw off a lot of the extra summer moisture.  ‘Big Money’ occupies the south end of the dry bed in the South Park Blocks next to Jefferson St across from the Art Museum.  These grow in a pumice amended soil topped with 1/4-10 gravel and because they are on an irrigation station shared with plants that want more water have low flow nozzles covering the area.  Separating the system would have been cost prohibitive given all of the piping and wires beneath the hard surfaces.  Others like ‘Canyon Snow’ have been scattered hither and yon in a variety of Parks.  All perform well, are beautiful and fill the area without fuss.  While not ‘native’ in the strictest sense they are trustworthy performers for our conditions and provide more color and presence than our local, tried and true resident, Iris tenax, which is still a valuable component along the woodland edge.


Iris x pacific ‘Montara’

Propagation by division is fairly simple and, provided your timing is right, you will have a high rate of success.  Their rhizomes are narrow, tough and stringy necessitating that they be cut.  Breaking won’t work as the rhizome will likely tear leaving more raw exposed tissue that is subject to rot.  When I divide I leave at least half of the plant in the ground undisturbed and make fairly large clumps of the rest which requires cleaning away most of the soil from them.  I’m not going for numbers as much as a blooming plant with higher survivability.


A sport  in my garden of Iris x pacifica ‘Drives You Wild’ or, perhaps a seedling growing within a clump (?), next to Filipendula ulmeria ‘Aurea’.  I divided this clump last Fall.  I’ll see what I end up with this spring during bloom time.

By extension, it is best to plant when they are in active growth so that they can become established before the stress of summer drought settles in.  Remember that summer dormancy means no root growth.  Fall rains bring the initiation of root growth.  Winter cold seems to work as a signal for the plant to begin the growth of new foliage and flowering as temperatures rise in the spring foliage occurring first.  I’ve never seen either the repeat flowering or the growth of new foliage here in the Fall that some summer drought stressed plants undergo with the onset of Fall rains.  All of the plants I’ve grown have been mid-late spring bloomers.  In the ground they need little supplemental water after establishment unless you are stressing them in a really hot location, though they will tolerate it with good drainage.  I don’t bother with dead heading in fact I do very little other than occasionally dividing them.

As evergreens there is a normal annual loss of leaves.  In a typical ‘cold’ winter I do get more foliage dieback.  Sometimes over half of a clump may appear dead and brown.  The leaves are persistent and do not easily fall or pull away, remember those fibers.  Over time they shrivel and curl.  Attempting to pull them away too vigorously may dislodge their roots.  In the Spring, where the dead leaves are older and ‘crispier’, these will form a ‘skirt’ around the perimeter and to a lesser degree within the clump, and can be pulled or broken off without damaging or tearing loose the plants. The more persistent of these I simply grab and cut low with secateurs.  Dec. ’09 brought more than the normal dieback and I was less careful cutting back removing some of the still green as well just as the flush of new Spring growth was beginning.  They take this in stride.  If you choose to cut them hard do so before they push their new spring growth otherwise this will weaken the plants forcing them to expend more energy ‘regrowing’ their foliage.  This grooming isn’t absolutely necessary as the flush of Spring growth will eventually visually dominate.

While some gardeners may see these as having limited value in the garden due to their relatively short bloom period and their lack of re-blooming, they fit in well in the ‘native’ garden or where the gardener has done more of a matrix style of planting so that other plants can ‘carry’ the aesthetic load helping to extend season of interest.  As a big fan of this group I have used them even in more ‘tropical’ themed plantings.  I look forward to their blooming every Spring!  Their foliage can also serve as a good foil for larger growing members of the garden providing presence throughout the year.  It will be interesting to see how they perform in the mass plantings recently made on the eastern approach to the new Sellwood Bridge, a very exposed site without help of a mixture of other plant material. Such a planting could suffer aesthetically should they fail even in part.  I’ve no idea which variety these are.  Native suppliers produce Iris douglasiana in larger quantities so I think it might likely be that, remembering that this species is more coastal and less tolerant of exposed inland conditions.

Iris-  series Californicae – by state

The species below are listed by the state(s) within which they occur.  The links are to species descriptions on the Society for Pacific Coast Iris’s site.

Californiabracteata, chrysophylla, douglasiana, fernaldii, hartwegii, innominata (occurence here is questioned), macrosiphion, munzii, purdyi, tenax, tenuissima, thompsonii

Oregon – bracteata, chrysophylla, douglasiana, innominata, tenax, thompsonii

Washington – tenax

Iris- series Evansia or Crested Iris

Oregon Iris tenuis or Clackamas Iris

Iris- series Longipetalae also occurring in other regions-

Iris longipetala which may be a lower elevation form of Iris missouriensis and Iris missouriensis or Western Blue Flag (found east of the Cascades, higher up in the Sierra Nevada and many areas in the Rockies



We have a huge regional nursery industry, but unfortunately, most of the material is sold back east, where plants like the Pacificas don’t perform.  Consequently, you have to look harder for these.  Stock in garden centers is sporadic and hybrids aren’t always labeled with their hybrid name.

Visit in spring:


22711 NW Gillihan Road, Portland, OR 97231  |  503-621-2233 [Sean often has some of the hybrids in his California/western/dry section] for those of you who don’t know on Sauvie Island


33326 S. Dickey Prairie Rd., P.O. Box 250, Molalla, OR 97038-0250; tel. (503) 829-3102; Email – [A score of different attractive PCI hybrids. Color catalog – $2.00].


608 NW 119th St., Vancouver, WA 98685; tel. (306) 573-4472 [Hybrids of Aitken, Jones, Ghio; Color catalog – $2.00].  I bought my first hybrids here 20 years ago at the same time that I was getting into Siberians.  They no longer list x pacifica in their catalog.


29730 Harvest Dr. SW, Albany, Oregon 97321; tel. (541)757-6521[grow several species]

Xera Plants

1114 SE Clay St. Portland, OR 97214 (503)236.8563  Xera produces a variety of hybrids and has made several notable selections of Oregon species, particularly of I. tenax and I. innominata.

CALIFORNIA: As many more people live here and much of the hybridizing happens here, California has more nurseries to shop from.


1201 Bay St., Santa Cruz, CA 95060; tel. (831) 423-3656 [Joseph J. Ghio; mostly his own hybrids; list catalog – $2.00].



27235 Highway 1, P.O. Box 258, Tomales, CA 94971; tel. (707) 878-2009 [West Coast natives and drought tolerant plants; several “Pacifica” iris species and named varieties].


San Luis Obispo County: 3232 Las Pilitas Road, Santa Margarita, CA 93453; tel. (805) 438-5992; San Diego County: 8331 Nelson Way, Escondito, CA 92026; tel (760) 749-5930 [Wholesale and mail order sales of a large selection of indigenous California plants; Irises may include I. douglasiana, fernaldii, hartwegii, macrosiphon, munzii, longipetala & missouriensis].


12511 San Mateo Road (Highway 92)
Half Moon Bay, CA  [They offer several Iris species and hybrids].


10459 Tuxford Street; Sun Valley, CA 91352; tel. (818) 768-1802 [Non-profit retail nursery open to the public year around. Many California native plants; Iris douglasiana, I. innominata, PCI hybrids and cultivars, seeds].

Visit the Society for Pacific Coast Native Iris at their website:


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