Iris unguicularis the winter iris (and a late June look-alike)

I'll bet that most gardeners, if they have any concept of winter-blooming garden irises at all, would think of the late winter blooming reticulate irises. Those who have checked out the genus iris a bit more thoroughly might be aware of some of the winter blooming scorpiris (Juno) species such as Iris rosenbachiana. But by and large these are specialists' plants which require careful management if they are to persist from year to year.

But as more and more of us in the greater Washington, D.C. area are discovering, there is another winter-blooming iris which, if carefully sited, deserves consideration as a reliable garden plant. That iris is Iris unguicularis in its several forms.

Looking back over the last ten or twenty years in this garden, I think one of the greatest sources of pleasure has been the discovery that yes, we can grow and flower Iris unguicularis in our climate. Forty or so years ago when I first attempted this plant the results were not good: although the plant itself survived from year to year, it never produced flowers. It did produce buds, but they always froze before opening.

I don't think there is another species of iris which has a longer period of bloom: the plants here bloom from early November into early April. The flowers generally come one or two at a time, although when conditions are just right the clumps might be ringed with bloom. And the individual blooms are substantial: they remind me a lot of the blooms of the late June blooming Iris brevicaulis (foliosa). I've included an image of Iris brevicaulis for comparison.

Three forms of this winter iris are grown here. Two are typical large forms, one is the small form often listed as Iris cretensis. The two large ones came without labels  from the local gardens of friends. In a sense, there is also a fourth form here, the plant known as Iris lazica. This one typically begins to bloom later than the others.

In the images above, you see first the two large forms, then the small, narrow leaved Iris cretensis, and then for comparison Iris lazica and Iris brevicaulis. Iris unguicularis, I. cretica and I. lazica are native to various sites in the Mediterranean region from northwestern Africa to the Black Sea. Some of the Greek forms show intense color combined with vivid patterning.  Iris brevicaulis is presumably not at all closely related to these as irises go: it's native to the south central United States.

The images of Iris unguicularis and I. cretica were taken today; the images of I. lazica and I. brevicaulis are from previous years.

I've seen these winter-blooming irises growing well and blooming freely in several local, northern Virginia gardens. Here in my garden the Iris cretensis and one of the Iris unguicularis are in cold frames; one of the Iris unguicularis grows in the open right against a sunny wall. And they all get covered in bitter weather. That's a small price to pay to have such big, colorful flowers in the garden during the winter.  

Iris lazica

Iris lazica is blooming freely now, and the big blue flowers are certainly welcome at this time of year. It's very similar to, and related to, Iris unguicularis. To tell the truth, I'm not sure how to tell them apart. Iris lazica has the reputation of being hardier than I. unguicularis, and for garden purposes it might be a better choice because hardier or not it generally blooms later. This year the two were in bloom for several weeks together.
The plant of Iris lazica growing here is in a cold frame, but I've seen it in the open garden in other local gardens.   

It's spring in the cold frames

We are in the throes - temporarily I hope - of another cold wave.  Recent mornings have brought temperature readings of 16⁰ F. Early bloomers outside in the garden are frozen stiff. But it's spring in the cold frames. If you look carefully, you should be able to make out four flowers of Iris unguicularis, the Algerian iris. To the right of the iris is a white-flowered Cyclamen persicum. And then there are the primroses. These are garden forms derived from Primula vulgaris (long known as P. acaulis).

What a pleasure it is on a day like this to bundle up, go out into the garden and open the frames to find a sight like this! This really cheers me up. And it matters not if the temperature again drops: all of these plants are snug in the cold frame.

The iris took a couple of years to dig in and begin to bloom: but you can see that it's now putting on a good show. The cyclamen was purchased either late in 2011 or very early in 2012: these deliciously scented plants bloom for months - they will probably still be in bloom in April! I bought the primroses last week at the grocery store. They cost all of three for five dollars: what a deal! In the house they would probably last only for a week or two before the heat gets them. In the cold frames they will go on for weeks as long as they are watered regularly.

Iris lazica

This is Iris lazica, a winter blooming species very close to Iris unguicularis (which  also blooms at this time of year).  Winter bloom is more likely if the plants have the protection of a cold frame (which this one does), although Iris lazica is evidently hardy enough to thrive in the open garden. But don't expect mid-winter flowers from plants in the open during a typically cold winter.

Digging for gold in the snow

I worked up the courage to uncover the most protected cold frames today. It was hard to get to them: when the neighbors cleared the snow from their driveway, they heaped it onto our lot. The cold frame area is surrounded by a three foot deep dyke of snow.

I have not yet opened the frames (there is still snow around the edges, and the space is so tight that I can’t easily get to it). But I got the snow off, and pulled back the protective tarps, and now light can get into the plants. They have been in the dark for….well, I forget just how long they have been covered up. The sunlight is intense at this time of year: it’s really pleasant to be outside now when the sun is shining – it’s actually very warm on the skin. And since almost everything is still snow covered, the overall light intensity is terrific.

Now that I’ve had a look, I can say that the news is good: there are no obvious signs of cold damage. At least one of the Chilean Tropaeolum (I’m obsessed with these this year) looks fine – I can’t see the other one yet.

From what I can see, everything looks just as it did when I covered things up before the last big snowfall. Not all of the plants in the frame are bulby things: there are some gerberas (in bloom) which seem to be taking to cold frame life very well. The big red Persian cyclamen is entering its fourth month of bloom. Some garden forms of Primula vulgaris seem to be in suspended animation: they don’t seem to have changed in weeks – the bright flowers go on and on.

The biggest surprise from this effort today came not from a plant actually in the cold frames but rather from one which grows wedged between the two cold frames: Iris unguicularis has a nice fat colorful bud up. And when I went in closer to examine this, I could see another flower of this iris which had evidently bloomed under the tarps and was not withered. This one is a real trouper!

What I call my Christmas snowdrop, which has been blooming since mid-December, is still blooming.

And a rooted cutting of Daphne odora is blooming sweetly.

Mourning doves, northern cardinals, Carolina chickadees and titmice were all singing this morning. The birds are obviously responding to the increasing length of the day rather than to the immediate conditions here in the garden.

In mid-April I probably would not take a second look at any of these things. But when you have to dig them out of the snow, they’re precious!

First week of January 2009

The garden has been good to me this first week of January 2009. Although it took some searching, there have been some things in bloom this week. And there are many things in “advanced bud”, so next week should be even better if the weather cooperates.
In the image above you can see some of the things now in bloom: Galanthus elwesii, Jasminum nudiflorum, Chimonanthus praecox ‘Luteus’, Hamamelis ‘Jelena’, H. ‘Feuerzauber’, Helleborus foetidus (with an unopened bud of one of the garden hellebores) and perhaps most surprising of all, Iris unguicularis: not bad for the first week of the year! There is also foliage of Arum italicum, Danaë racemosa, Hedera helix and Sarcococca humilis.
Crocus ochroleucus is blooming in one of the cold frames, and in the protected frame some of the white-flowered hoop petticoat daffodils are about to bloom, too. Out in the garden, Sarcococca humilis is heavily budded and the first Camellia japonica of the year are opening.

The image above was done indoors early in the evening: we've had no sun for days now. It was cropped and rotated and as a result the image quality has suffered. This softening of line and lack of crisp detail, which some might see as defects, nevertheless give the image the quality seen in early twentieth century color images. Think Gartenschönheit in the early twenties. I guess I've just snubbed my nose at nearly a century of technological advancement in photography.

Early January 2009

So, what does the garden have to offer this first week of January?

Nighttime temperatures have been regularly dropping into the low 20s F lately, so I had no hopes for a long list. And the short list is indeed short, but it includes some flowers which make a trip out into the otherwise quiet garden well worthwhile. Here it is: Jasminum nudiflorum, Galanthus elwesii, Chimonanthus praecox, Helleborus foetidus and Iris unguicularis. In one of the unprotected cold frames Crocus ochroleucus is blooming.

In the protected cold frame, some of the little white-flowered hoop petticoat daffodils are about to bloom, as are Narcissus tazetta ‘Ziva’ and N. pachybolbus. This last is a white-flowered daffodil of the tazetta group, smaller in all parts except its bulb than ‘Ziva’.

The handsomest of all of these, and – given the weather - the most unseemly, is Iris unguicularis, the Algerian iris. This grows in the open air planted right against a wall of the house. It gets covered nightly. Last year I discovered that it will reward this slight bother with intermittent bloom from November until April. At this time of year it's a real treat to linger over this plant and soak up the gorgeous color.

While walking Biscuit the other day I noticed that the buds of Acer rubrum seemed to be swollen a bit: it’s ready to go, too.

The Algerian Iris

The tradition of making lists of plants blooming on Christmas or New Year’s Day is one which has never really caught on in our climate. Winters here have generally been too severe to make it worthwhile. Yet recent winters have more people giving the garden a careful look during the holiday season.

This year the garden has given me an utterly unexpected gift: late this morning I noticed a newly opened flower of Iris unguicularis, the Algerian iris. This particular plant has been blooming since sometime in November. It was obtained in the summer of 2005, planted against the house wall with a SW exposure in the rain shadow of the eaves – and then forgotten. It first bloomed in late November of 2006: that first flower (shown above) was improbably big for something blooming outside at that time of year.

This area is not Algerian iris country. English writers from Gertrude Jekyll a century ago to those of the present have celebrated this beautiful plant, and many American gardeners have tried to grow it. I certainly did several decades ago; but that trial, although it resulted in healthy, robust plants, produced not one mature bloom. There were buds, but never a flower. The buds always froze before they opened. I eventually gave up on the plant.

Then another local gardener had a repeat of my luck: he tried the plant and it never bloomed for him. He dug the plant, divided it up, and offered the pieces at a meeting of our local rock garden group. I was not the only person to take a piece, but as far as I’m aware I’m the only one who has reported success with it. The very mild weather has a lot, maybe everything, to do with it.

Now that I’ve seen what this plant can do, I might make room for it in the protected cold frame. That way, if typical winters return, I’ll still have these amazing blooms to brighten the shortest days of the year.