Starting again with Pacifica Iris

by Kathleen Sayce 

When I began focusing on irises more than 20 years ago, I was eager to hybridize for deeply saturated colors and weather-resistant flowers and plants for my climate and soil, near the Pacific Ocean in southern Washington State.

Iris tenax flowering in the yard: not exotic, but thrives in our soil and weather

I ordered Pacifica iris divisions from several different growers, amended the soil in key beds, and planted these new starts. I also ordered seeds from the annual Society for Pacific Coast Native Irises (SPCNI) seed exchange. [Note: The December 22/January 23 catalog is about to go live on the SPCNI website, writing in early December 2022.] I made tags, started a hybrids notebook, and worked out a unique scheme for each cross. I started testing kitchen countertop paper chromatography solutions so I could check flower pigments in crosses. 

Then I sat back and waited to see how everything grew. Well, I actually kept weeding and planting and enjoying these new plants. No sitting back was involved.

What happened? Not what I expected. 

Iris tenax clump

First, jays, squirrels, and crows pulled tags every chance they got. I found tags scattered all over my yard, on the driveway, and even on the access lane hundreds of feet away. We had feral peacocks in the neighborhood for several years. They pulled tags, and plants too, if those plants were growing where they decided they had to have dust baths. 

Those same species all love fresh young iris seedlings, it turns out. Mesh covers help; I now put all my seed pots in mesh frames. 

Deer tugged seedlings out of the ground to check palatability. Repeatedly. This led to arguments with adorable spouse, who does not want a fenced yard. The deer were eventually followed by a local herd of elk, who eat everything remotely palatable and trample the rest. Adorable spouse still does not want a fence. 

The weather got in the way of making deliberate crosses. Strafing rain in March-April-May can do that. Even bumblebee-assisted pollinations suffer in hard rain. I tried putting covers over plants, but it is just too wet and cold most years for pollen to germinate. I might try a modified alpine house, open on the sides for good airflow, to control the moisture; though then I'd have to water. 

Heavy rain also damaged petals, especially on more recent, highly-frilled hybrids. Given that these tend to flower during mid-spring, which is often very wet, it became clear that I needed to shift to later flowering selections. I started to focus  on Iris tenax instead of hybrids in the Pacifica iris gene pool. 

Then I misplaced the notebook! It was a strong sign, I decided, that my iris activities should be limited to growing and enjoying. 

Years later, reading an introductory chapter on growing Pacific Coast irises by Adele and Lewis Lawyer, they stated that Pacifica iris do not like sandy soils. My garden has silty sand. Hmm. If I took them at their word, I would never have tried growing Pacificas! 

All I can say is I would have missed a lot of entertainment over the past several decades. 

Watching for first Pacifica Iris flowers, or the Uncertainty of Gardening

Kathleen Sayce

Over the years, a variety of invertebrates and vertebrate flower-eating varmints have made their presences known in my garden. 

PCI 'Finger Pointing' is a lovely early flowering PCI, but fails to flower in many years due to wet windy weather. Seed set is also erratic due to vagaries of weather. 

Slugs and snails normally disdain irises in general and Pacifica Iris in particular, but not when there are young, tender leaves to be had early in the year, or tasty young flower buds. One of the better reasons to pull old leaves and winter debris from the iris beds is to reduce hiding places for slugs and snails.

A tidied up PCI plant. Not shown:  the five small snails and slugs that were removed with the dead leaves and winter debris. 

Then there are Stellar's Jays, which find germinating iris seeds and seedlings to be a delicacy. Black-tailed Deer also like Pacifica iris shoots, at least the first few mouthfuls, before they start spitting them out and leaving them alone.

And then the chipmunks moved in, capable of disbudding entire flower beds in one night. It's enough to make me think about an outside cat!

Right in the center of this image, the former flower bud, with the pedicle still visible between the bracts. Guilty party––a chipmunk. 

Jays and other seed eating birds drove me to use wire mesh to cover seed boxes. Once the seedlings are more than four inches tall, even the deer leave them alone, but until then these must be like alfalfa sprouts to them, young and tasty.

The weather doesn't help. Heavy rain and hailstorms in April and May often end the flower display from many a well known hybrid Pacifica Iris. I've used temporary covers over plants so that I can at least get a few photos of flowers. But there's a maxim that if the weather is wet enough to ruin early flowers, then protecting them won't help seed set, because the bees don't like rain and hail any more than the flowers do.

Rain screen deployed over a PCI plant. 

The flowering sequence at my latitude (46 N) is something like this: Modern PCI hybrids begin flowering in April, with the exception of PCI 'Premonition of Spring', which flowers off and on from September to April. This group continues to flower into May. In late April to May, many older Iris douglasiana selections come into flower, including PCI 'Canyon Snow' and 'Cape Ferrello'. In June, species irises begin flowering, including Iris tenax, I chrysophylla and I. innominata. A patch of I. tenax x I. innominata plants regularly flower into late June, and sometimes into early July. Some dwarf I. douglasiana plants also flower in June.

PCI 'Blue Plate Special' is ready to flower in early April. 

At the same time, Iris tenax is just getting started with new leaves. The difference is that the latter plant will flower better, and probably set more seeds, by flowering in June. In my climate, that makes a huge difference. 

Given a tendency lately for weather to be too wet in April, and too hot in May for good seed set, often it's the late flowering species and species crosses that do the best. I've come to treasure the durable late flowering plants, because they are more reliable than the gorgeous, early flowering hybrids.

PCI 'Blue Plate Special' in bud––a beautiful sight, but will there be flowers to follow? Only Pluvius, the god of rain, knows. 

Part Two: Remineralizing soils and the PCI response in my Garden

Kathleen Sayce

Yes, as a result of my soil experiments there were more flowers than ever in my garden in 2013. But it's the number of Pacific Coast Iris (PCI) pods that was astounding. In prior years I'd seen around 50-70 seed pods in total. I know this because I use organza mesh bags on ripening pods to keep them from tossing seeds all over the garden, and I could count the bags as they went out. I'd purchased 400 bags and used 70 in 2012, on every pod I could find. And this had seemed typical at the time, based on prior years' seed sets.

Tools of the seed collecting trade:  mesh bags, paper bags, and somewhere in the bottom of the basket, a writing implement and clippers. 

By 2013 I used every mesh bag, some of them several times, shifting from early ripening pods to later ripening pods. A friend found a few more bags at a yard sale and gave them to me; I used them as well. I cut pods off many plants, needing at most 15 pods of each variety for the SPCNI seed exchange, and threw away at least 100 pods. So in one twelve-month period, my irises went from producing around 70 pods, to producing around 500 pods. The only thing that changed was the soil's mineral nutrition.

Some of the extra pods.  Look closely at the top of the image to see seeds spilling out in the lawn. Just a few of the many pods I tossed in 2014, from the plants that set seeds.

There was also a major weather difference that reduced the seed set for many PCI. Many of my well established plants are hybrids that flower in May and early June. A typical year has PCI in flower from April until late June or early July. We had a late wet spring in 2013. I did not get any seeds from the early flowering PCI. The later flowering species and species crosses that bloomed in mid June were more successful, as they flowered in drier weather, and bumblebees could actually get to their flowers. So this astounding pod production was despite very poor early-season weather for seed setting.

One hybrid I very much wanted seed from, 'Finger Pointing', did not set any seed at all!

PCI 'Finger Pointing' managed to hit the wrong weather to set seed in 2014. 

In 2014, I resampled the soil, had another mix of minerals formulated based on the new soil test, put these out in winter––this time we did it all in one application, and then I again waited for spring. I also added compost to most beds, and continued to plant new plants with a mix of compost and biochar. My hope is that these high-test carbon compounds will help with mineral retention in coming years. Ongoing soil tests will tell me how successful this is.

Again the weather did not cooperate. In spring 2014, my area had an early, very warm hot spell that lasted several weeks, with temperatures in the low 90s to low 100s––for the South Coast of Washington, it was hot. In response, irises that normally flower over three to four months all flowered in less than six weeks. The bumblebees were badly overworked! Early flowering (April to early May) PCI responded with heavy seed sets and a short intense flowering period. This unseasonal heat was followed by cool rainy weather in late May into June, so late flowering PCI did not set as much seed, the reverse of the prior year, though the tenax x innominata plants again set many extra pods. I once again used all my mesh bags, and again cut off more than 100 extra flower spikes with more than 200 pods to reduce final seed volumes on those plants that did set seed.

PCI 'Mission Santa Cruz' is an old, tried and still true iris for gardens. Even this one failed to set any seed in 2014. 

Observant readers will note that I have not written about Nitrogen or N-P-K formulas. I did not add N or N-P-K in 2013 or 2014. A properly mineralized soil does not need much N. When healthy, the soil contains microorganisms that fix N and make it available to plants. There's another very important reason to not add N: Nitrogen fertilizers stimulate microbes to metabolize carbon compounds in the soil. My soil is acidic sand; I do not want to lose any carbon if I can find a way avoid it. Also, post World War II, the use of N fertilizers has wreaked havoc with historic soil carbon levels around the world. So I save money by not using standard N-P-K mixes, and instead spend it on custom blends.

If you read about historic versus current levels of minerals in vegetables, it's staggering to learn that mineral levels in food plants have dropped by 3-10X from those of a century ago. This bears directly on food health for all of us, as well as flowering and seed setting capacity for those plants we eat, not to mention those we grow for pleasure. It seems clear that improving minerals in soils leads to improved seed sets (see Jeff Lowenfel's Teaming with Minerals).

Other gardeners have commented on my use of inoculated wood chips. Most native plants in the West, especially in forest and woodland conditions, grow with soil fungi. In my garden,it is a measure of success to have mushrooms growing among ornamental plants. When I dig up iris plants, I see abundant feeder roots interacting with aged wood chips and soil fungi. In Fall 2013, chanterelle fungi were fruiting on a garden path next to several iris plants; this path is layered with several years worth of wood chips. Success!

In Winter 2015 I'm about to sample my soil again, and take the results to my local soil consultant. I can't wait to see how my PCI respond this spring. No guesses on the weather, though. In the past two years, I've seen both early and late flowering plants shut out by weather from successful seed sets. What I do know is that those PCI that manage to set seed are likely to set a lot of it!