This past year I was the recipient of a Chanticleer Garden Scholarship awarded to professionals in Public Gardening, in my case to do a floristic and cultural comparison of two mountains in Greece and Turkey which have both been called Mount Olympus in past centuries. As often occurs, I encountered some wonderful things en route that are well worth sharing…in my case, a stopover in Reykjavik, Iceland on my way to Europe.</p> As a young man, I envied my friends who flew the old Icelandic Air and had stopovers on that island. The new Iceland Air has renewed this option, and I hopped on the chance to spend a day in the capital city. The airplane arrived about 6 a.m. Being June 27, it was bright as mid-day at that time! I had almost 18 hours (all in full daytime) to explore, and naturally, I went straight to the Botanical Garden which is a short bus ride from the downtown area.</p> Needless to say, I felt right at home when one of the first plants to greet me was a superb specimen of Colorado Columbine in glorious peak bloom! The rock garden at this garden is situated right at the front gate, and it is perhaps their best garden feature—wonderful use of stones, and a mind-boggling collection of choice alpine plants, many of which I’d never seen before.</p> I have never seen the rare European yellow columbine (Aquilegia aurea</em>) anywhere else in cultivation in any public or private garden, except for a brief appearance here in Denver several decades ago. Seeing this made me determined to find seed and grow it in Denver once again (see the gallery featuring images of all of these plants).</p> I was also deeply impressed by a wonderful spread of the golden saxifrage (Chrysoplenium tetrandrum</em>) an unusual circumboreal alpine. I have seen this in a few gardens before, and I’ve found it growing wild in Kazakhstan. What galled me, however, finding this here was that this is one of the few native Colorado wildflowers that I’ve never seen growing in nature in Colorado, although it has been found several times just an hour or so drive from Denver proper (on Mount Evans for instance). And here I’m finding it first in a garden in Iceland. You can see why I was a tad jealous!</p> Few people would mistake this for a Saxifrage—this strange group of “rock breakers” are found mostly in the Himalayas where come in other colors and strange forms. I find this to be fascinating, and am determined to find it in one of its dozen or so Colorado locations in the summer of 2016.</p> Another old friend I never expected to find in Iceland was the miniature yellow ice plant—not the familiar D. nubigenum</em>, but a more congested, high alpine species that is going about under various names. I now think the best name for it may be D. congestum</em>, since it seems to most closely fit the description of that species.</p> This bloomed for us in Denver in April, ending in early May—so it speaks volumes about the climate in Reykjavik that it was still blooming there at the tail end of June.</p> One plant you will NOT find blooming at Denver Botanic Gardens is the blue poppy. They had many fine specimens of this famous and spectacular alpine at Reykjavik Botanic Garden. We have coaxed a bloom or two on these in Denver, but they resent our summer heat. Iceland suits them to a “T” and they were nearly 4’ tall, with glorious blue color. I believe this is Meconopsis grandis</em>, or more likely a hybrid of it—this is one of the few specimens without conspicuous labels at this wonderful garden.</p> I should have expected to see a lot of willows—the genus Salix</em> is especially diverse in cool, moist climates. I did not expect to see dozens of species, nor to see Salix lanata</em> used as a hedge in the downtown shopping areas or along city streets! The catkins were in perfect bloom during my visit!</p> This last shot captures something of the remarkable magic of the climate in Iceland: the weather is cool enough that tulips are still in full bloom at the end of June, but warm enough that South African bulbs like Crocosmia</em> ‘Lucifer’ are thriving and blooming alongside the tulips.</p> There are many scenic and cultural wonders in Iceland as well…but I heartily recommend a visit to their gem of a public garden if you happen to take Iceland Air up on their stopover offer!</p>
Iris 'Lady Beatrix Stanley'</p> As I was driving home yesterday I passed a house which boasted a narrow bed along its north side with hundreds--maybe thousands of snowdrops. I began looking intently (through Capitol Hill mind you--one of Denver's most plant-dense neighborhoods). Surely there must be more bulbs out? A block or two later I saw a fabulous stand of crocuses in the corner of one lot, then nothing in the way of bulbs the next mile or so home.</p> Friends: Denver is BULB country: Denver Botanic Gardens is positively LOUSY with bulbs right now...let's take the reticulate iris as a case in point. They're called netted iris, by the way, because their bulbs are swathed in a netted tunic--although some think it's because their flowers are often netted with fine lines of color. The picture above shows a wonderful stand of Iris</em> 'Lady Beatrix Stanley' positively GLOWING in the Plant Select Garden. Don't miss it! This is a hybrid of the next species, and it has become widely (and cheaply) available in recent years. There's no excuse for us not to have it in our gardens except sheer laziness! (I better get on the stick and order some this spring</a> so I can be even more self-righteous NEXT</em> year!) Since it is missing from my own garden...(oh yes, the title: I am NETtled that more NETted iris are not ordered over the interNET!!)</p> Iris histrioides 'Major'</p> This is a tale of woe! Once widely available in the Dutch bulb trade, the family that grew this commercially ceased to do so decades ago. You'd be hard put to find this nowadays. This plant has persisted in this one spot in the Rock Alpine Garden since 1984. That's 30 years worth of flowers! Perhaps our meritorious staff in that garden may want to think about dividing and spreading this about in this vicinity this summer? (hint hint)...</p> Iris 'Katharine Hodgkin'</p> I remember when this was a fabulously expensive bulb a few decades ago (1970's to be more precise). I have rhapsodized about this amazing plant</a> at length elsewhere. Suffice it to say the several dozen bulbs I planted in my rock garden a few years ago all perished the winter before this one when we had our disastrous April freeze. The ones at the Botanic Gardens came through unscathed. Not that I'm bitter or anything. See these now in glory in the O'Fallon Perennial border.</p> Iris 'Harmony'</p> Harmony indeed! Just LOOK at that clump--this one is in the upper meadow of the Rock Alpine Garden. I have not often seen these iris clump up so thickly! When they do, however, they become susceptible to Ink blight--a dread fungus that loves to do in reticulatas. It will be interesting to see if these come back NEXT year...the bulbs are so inexpensive, it's almost not worth the effort to divide these. I have done so right after they bloom when their in full leaf and find it works well.</p> Iris 'George'</p> I should have put a ruler next to this monster--it's almost a foot in height! Tucked at the back of the Rock Alpine Garden, George loves this spot and is the largest of its kind I've ever seen. It is (like 'Lady Beatrix Stanley' and 'Katharine Hodkin') likely a hybrid of the true Iris histrioides</em>: which is not available in commerce at all (and may never have been). Except for 'Major', that is: the Dutch select all of these plants for their vegetative vigor: they're all reproduced form bulb divisions.</p> The bulbs that do this best are generally sterile hybrids--as a consequence none of these reticulate irises seem to set seed in Colorado. There are a few wild forms in cultivation (I have a few in my house), and these might actually reproduce from seed in our conditions. Which I would love to see happen. As long as we grow these mules, we shall have to divide them on a three or four year sequence to keep them from overcrowding and dying.</p> Iris 'J.S. Dijt'</p> I finish with another classic: the deep purple form of Iris reticulata</em>, growing in the Lilac Garden. These were planted ten or more years ago, and are still thriving.</p> Reticulate iris have been put in their own genus by the great Russian botanist, Rodionenko: Iriodictyon</em>. I have a hunch he's correct. They are as easily grown as crocuses, and far less often seen. I think we're missing out by not planting these on a massive scale throughout our region where they do so well.</p> Once you have several hundred (or let's say a THOUSAND) of your generic, Dutch hybrid reticulatas scampering all over your garden...then and ONLY then you can click on the U.R.L.</a> and see that a vast universe of hybrids is being generated by a mad Canadian I met decades ago when he (and I) were mere babes in the woods horticulturally. I'm speaking of Alan McMurtrie. Some day I'll blog about him more fully.</p> Until then, come wander through the Gardens and marvel at our bulbs, and jot down the ones you would love to see in your garden next spring. Denver Botanic Gardens has online bulb pre-ordering happening now!</strong></a> Here is a catalog of the bulbs that are for sale and how you can order.</a> Get a jump on your spring gardening. Place your bulb order between now and June 22, 2015 to reserve them for easy, hassle-free pick up in September!</p>
Salvia indica</em></p> The first salvia to bloom at Denver Botanic Gardens every spring is actually from Western Asia and Turkey rather than India as the name would imply. It shows one extreme of the range of form the genus can display. Now look below at a Western American gem:</p> Salvia pachyphylla</em></p> Over the last few decades, a veritable flood of sages have become available commercially at local garden centers. Some, like this Mojave Sage (Salvia pachyphylla</em>) thanks to Plant Select</a>. Most are very xeric, and many bloom for months on end, starting in May. Since the genus Salvia may contain over a thousand species, and probably even more hybrids, no wonder some gardeners are frustrated at what to grow in their gardens.</p> Why not sign up for my upcoming class, Genus Salvia for Colorado Gardens.</a> I originally prepared the precursor to this talk for a Symposium at Huntington Botanical Garden in 2014 and reworked for our local conditions. It represents my summation of growing over 100 kinds of salvia over the last few decades. There is a salvia for almost any condition in your garden, sunny or shady, wet or unwatered. Many salvias available through local garden centers are barely represented in books, and little known outside our region.</p> Salvia pisidica</em></p> This wonderful groundcover is a good example of an outstanding Xeriscape salvia from southeastern Turkey that was introduced to horticulture 30 years ago by Jim Archibald, but Denver is one of the few places where it's made itself at home! This has been offered at our plant sale for years, but few realize what a wonderful evergreen, xeric groundcover it is. This picture was taken in Mike Kintgen's private garden but fabulous spreads of this plants can also be found at the Denver Botanic Gardens in the Rock Alpine Garden</a> and the Gardens at Kendrick Lake. There are many spectacular salvias from the Mediterranean and Asia that were introduced here at Denver Botanic Gardens, and these will be a focus of the talk.</p> Salvia penstemonoides</em></p> Here is another spectacular salvia growing at Mike Bone's private garden which he has propagated at sold at our spring sales several years now. Thought to be extinct, the "Penstemon salvia" was rediscovered twenty years ago, and has been propagated and shared widely by plantsmen--and it has become a long-blooming spectacular plant for a xeriscape or dry border in Colorado.</p> Salvia caespitosa</em></p> There are even tiny species like this one that you can grow in a rock garden or large trough. And there's a vast world of tropical salvias that make wonderful bedding plants and elements of the summer and autumn garden.</p> I believe there will be many more spectacular salvias showing up in our gardens in the next few years--and you can get a sneak preview on Wednesday night, March 11 here at the Gardens! Press here for registration details</a>.</p> </p> </p>
Aloe polyphylla</em> at Semonkong Lodge</p> Few plants better epitomize the quandaries of plant conservation than this iconic aloe, endemic to the heights of south-central Lesotho, South Africa. Once relatively abundant (Alan Beverly estimated at least 10,000 a half century ago), this magnificent national flower of Lesotho has become extremely rare in nature...although increasingly abundant in gardens.</p> Aloe polyphylla at Malealea, southern Lesotho</p> There is reputedly a nursery selling plants in Lesotho grown from seed, but as I travelled around the country, I only saw massive plants like these that I suspect where harvested in the wild. Wild collection is certainly one reason that so few of these are still found growing wild--that and the fact that they make a fascinating sound when giant rocks are tossed into them (the countryside is filled with bored, young pastoralists who are very efficient at lots of things--killing anything that moves, and killing aloes).</p> Aloe at a typical roundeval in Lesotho</p> Again and again as we drove through villages I'd notice spiral aloes growing at this or that roundeval: happy and quite enormous. I didn't notice any little ones--perhaps they were there?</p> Of course, collecting even seed of this is strictly prohibited, the sale of large specimens especially so (and always has been). Nevertheless, Aloe polyphylla</em> has been firmly established in cultivation over the last half century. In fact, some nurseries in California have enormous stock beds that are beginning to produce vast quantities of seed. I have seen plants marketed quite cheaply at Denver area garden centers the last few years--some by Monrovia, one of the largest growers in the country.</p> Colorado columbines are sold by the thousand (if not million) each year in our area--and never cease to retain their glamour and beauty as a consequence. Is the Spiral Aloe diminished if it becomes more widely available commercially? I don't think so. The solution to pollution is dilution--a well known adage. I'd like to coin a new one: the Salvation from Depradation is Propagation!</p> If this plant had not slipped into cultivation decades ago, I believe it would truly be in peril of disappearance. I believe one day those cultivated plants may provide a gene pool that could re-stock the wild populations that have succumbed to the destruction that often comes to plants in poor countries that have little in the way of environmental education or enforcement. </p>
