Thursday, May 11, 2017

Pilgrimage to The Crevice Garden Capitol of Crevice Gardening #1


This is day two in the rich midst of 140 experts, specialists, amateurs, botanists, horticulturists, and mad plant people from around the world, here at the

Third Czech International 
Rock Garden Conference

in Průhonice,  outside of Prague Czechia (Czech Republic)

It's being held just steps from UNESCO World Heritage Site, Průhonice Park, in which the above rock garden is kept.  That rock garden goes on for acres/hectares with a narrow, steep, informal path. We were all very impressed at the size and how keeping it informal (not painfully tidy) made it possible to have so much garden a person can be totally immersed in for half to a full hour walking, so that the visitor feels like he/she is in a wildflower mountainside daydream, rather than looking at an installation of rocks and plants.   The rock garden is just a part of the park wrapped around a pond, edged by a Castle, with 40 kilometers of walking path. A marvelously indistinguishable meld of park, forest, and garden which fools you into feeling you are in nature; something I am not sure that North American gardens or parks do.   



From a horticulture and maintenance standpoint, I was deeply impressed by the minimal yet effective (efficient) style of maintenance: a careful balance.  It is managed en masse, not fussy, and it totally works.  But I understand it still takes over a hundred staff to do it.



Much note-taking, business-card-sharing, and sketching has been happening during programs.  Ideas are passing hot like soccer balls at the world cup.  No, those aren't even my sketched, but it is my cuppa tea.

It's intense!  Not only are piles of old friends catching up with one another at every break and meal, sharing their newest experiences in growing plants, but the official educational programs run from 9 am to 11 pm!  At least a third of the group actually stayed up late to attend all the late-night lectures tonight, including a gorgeous travelogue from plant hunter Julia Corden on the elusive himalayan blue (and other color) poppies.

Hard core plant lovers here.


Paul and I enjoyed an evening and morning wander through the garden of the contemporary godfather of Crevice Gardening, Zdeněk Zvolánek.  His own garden southwest of Prague is a massive and steep "Beauty Slope" integrated into and sourced from a present real rock outcrop.
The paths are narrow and full of plants. Less room for weeds, more room for garden.

He is a shameless user of Sempervivums in every shade and shape; they make useful and non-competitive coverage in crevices, for they play well with others and do not overwhelm prized cushion and bun plants.  And look at the color they add!


Iris reichenbachii 'Balkana'

The (Spanish) Blue Gorse, and spiny heartthrob of mine, Erinacea anthyllis.  

Vigorous rock garden plants which do not need irrigation but are not too aggressive to contain are allowed to fill all niches; leaving little room for weeds.  For- it's very near  being steep enough to need climbing gear for  Mr. Zvolánek to access his planted slope.  You are looking at a south-facing dense matrix of Aethionema, Linum, Aubretia, Sempervivum,  Globularia, Dianthus and Campanula, with choice showings of Daphe, Acantholimon, Genista, Dwarf conifers, and Moltkia.

His style and approach certainly takes a great deal of actual work- hand labor to keep it going, but it is done with a finesse and deep intelligence of the plants where he plays a balance, between grown and overgrown, aggressive and weak, tended and unkempt, so that there is not a giant, unnecessary effort to make the garden do things it doesn't want to. He gently pushes the plants towards thriving, the energy is so un-forced that the garden exudes it and even the visitor can be relaxed while stimulated at the sheer volume of incredible plants.

A living masterstroke of genius.



Monday, May 8, 2017

Fresh Things: In Nature

Actostaphylos patula.
The Greenleaf Manzanita, 7700 feet up (2300m). Southwest of Grand Junction, Colorado, USA
A particularly dark pink plant. 

I have never seem them bloom so heavily in my life.



Not too far away, Colorado's highest-elevation cactus (as far as I know) is the Mountain Ball, or Pediocactus simpsonii, which here is just shy of basketball size, adding "grandma's house" fragrance to the air, Allen (background) noted.

It's worth risking a little prickle to your nose to experience the fragrance.

A new plant to me, the first flowers mere millimeters wide following snowmelt in the Flat Tops area of Northwest Colorado, is the carrot-family's Orogenia linearifolia.  It has a little not-even pingpong ball sized corm giving it the "Indian Potato" moniker. 

It's special because it is literally the first and only flower right now in bloom at mid-high elevation, patiently getting buried in intermittent, melting, spring snows.

A strange, whole-leafed form. (Usually, Orogenia linearifolia has split, thin leaflets which cluster, looking like a tony tuft of grass. Note the charming leaflike-sheath below it all which enclosed and protected everything as the plant waited, mostly grown but hiding in that sheath ready to unfurl as the wildernesses real first flower, content with gentle flies for pollinators.  "Often overlooked..." According to Ackerfield.  I can see why.  It's not half an inch (12mm) tall.



Fresh Things: In Gardens


My granite crevice garden with golden-groove bamboo (Phyllostachys aureosulcata) in the background, which in its yearly ugliness in this climate, begs me to finally tear it all out.

Crevice Gardens are starting to peak in bloom, like mine here, which is probably why the International Rock Gardening Conference is about to happen Wednesday in Prague. Oh, I'l be there, yes, thanks to Denver's Rock Garden Club: RMC-NARGS, who graciously sponsored my trip and for whom I'll be reporting everything I dig up.  Just the best crevice gardens on the planet will be on show, that's all, and the world's finest plant-collecting talent will be presenting programs.

Stay tuned for  updates this week as Paul Spriggs and I dig deep into Czech rock garden history and pick every rock garden innovator's brain for every trick they have.

Iris acutiloba ssp. lineolata.  These things always bloom when I'm out of town.  So I schedule a trip, then go a day later so as to catch them in bloom the day I leave...  It and its onco iris kin are the reason for the crevice garden's construction, and luckily they like it.  Next door to it is a native mint shrub:  Monardella odoratissima, and it grows in the West Elks in Colorado (where I probably got my seed) and in the La Sals, which are the backdrop to Arches National Park outside of Moab, Utah.


An old friend.  Or foe. "Frenemy" as we millenials say. An aggressive friend. Colorado native skullcap, Scutellaria britonii, is an shameless underground spreader and must either be put in check every spring it shows up everywhere or planted in a place where it can go nuts.  Think 4-7 feet (1-2m) expansion underground per year.  It gives spring weeds like Dandelions something to contend with; I am trying it as an underplanting for warm season clump grasses.  It goes dormant soon after blooming.  You should see the piles of pearl-necklace like underground rhizomes.

New to me, and an exciting Southwestern US native which not only seems small enough for a rock garden, even crevice garden (said to be a limestone chasmophyte in nature) but is red!   Salvia henryi,   grown from Alplains (NM) seed, has been super easy to germinate and grow in the home nursery. I'm excited to try it in the ground; I think it will nicely replace the habit of Verbascum rupestre  which had to be kicked out of the garden for its terrifically agressive reseeding.  Except this is red!  Red!  


Many people have asked if Joshuatrees would grow here in Grand Junction, CO. (Yucca brevifolia) Here is the answer: seed-grown plants ( I think young is the key- most transplants fail) by Don Campbell are about 12 years old and taking on real character, several feet taller than a person now.  CSU extension office demonstration gardens, at the Mesa County Fairgrounds- this is the Cactus Club's section.

It's amazing how natives quickly fill the niches weeds had.  Oenothera caespitosa and Sphaeralcea munroana take to the cracks!

Spring number two, the radio station garden is filling in nicely.  Stanleya pinnata (yellow) does most of its growth in very early spring for a big brassicaceous romp in Late April/May- the desert US answere to Asia's Eremurus. The Penstemon eatonii, perhaps thanks to a snowy winter (read: well charged soil) has reseeded madly, and we're not stopping it.  Next year will be a firestorm.

In the ongoing quest to find the perfect way to grow Paintbrush (Castilleja), here is Castilleja integra  planted with two plants as hosts: Penstemon secundiflorus (which can be short-lived) and Echinocereus triglochidiatus/mojavensis (Which is long-lived - the Claret Cup Cactus).  My feeling is that the best host is a strong host; for Castilleja  seems capable of killing weak plants.  Now, I favor small, established shrubs like Black Sagebrush, Artemisia (tridentata v.) nova, Yucca sp, Agave, et cetera.  In a perfect world, you will plant a new Castilleja  with it's roots touching a healthy plant which has been there and established for a few years.  It's working.

Penstemon acaulis, luckily two plants here, promises good seed this year.  I pray it doesn't spill away before I get home to collect it.  A testament to the efficacy of the clay- laced crevice.


Tuesday, March 7, 2017

Voted best Townsendia

By me.

For the lazy gardener like myself who wants long-lived. Which is a real complaint to be made about many townsendias (Townsend Daisies) in the garden.  I've grown about a dozen species, and none were bad.  But I've passed that kick, and Townsendia hookeri persists.  It seems adaptable to clay and sandy soils.  Mine is in clay, in a dry rockery (watered ten times per year: bimonthly in summer).  They usually bloom in February.



Also super easy from seed and blooms the year after sowing.  (I recommend winter-sowing with a peagravel topdressing in small pots.)  It's generally from the Eastern slope of Colorado all up the prairie into Western Cananda, but it shows up in some of our dry Western Mountains among sagebrush, too, where its geodesic seed heads open to tumble into the wind like so many blown kisses.







If I were a romantic landscaper who wanted long-lived plants for laymen clients who aren't the kind of hardcore hobbyist to home-grow scads of replacement plants, but I wanted to hook them on rock garden plants, this would be a good one.



Oh wait, I am.




Monday, March 6, 2017

Paintbrush's Flagship Manzanita Prop Campaign

Our propagator, Allen, instagrams the good news of our first 'Zita baby with root.  This is a cutting from Colorado's elusive Artostaphylos patula:

A post shared by Paintbrush Gardens (@paintbrushgardens) on



I managed once to germinate this plant well from seed, and failed to record how.  I've never succeeded since.  The pain of that mistake has turned me into a religious record keeper.  For now, we'll grow her from cuttings until I find that black magic I used before.



Until then, know this on the culture of Manzanitas in gardens, where intermountain folks like us are concerned:

True manzanitas are tall, bush-like, hip-high and taller.



Their little sister, Kinnikinnik, (Arctostaphylos uva-ursi) is a short ground-cover of the high mountains. When the two mix in nature, they create the more domesticatable garden/landscape-friendly natural hybrids which are becoming available now, like 'Panchito,' 'Bulbous,' "Mock Bearberry" a few others, and my favorite:  'Chieftain.'    These mixed-blood wonders are your best bets if you want reliability.

'Panchito' is much easier; a rugged donkey. He does not seem to need the sandy soil.  He takes clay, sun, shade, and can be purchased in decent nurseries all over the west because he's so much easier to propagate from cuttings.  An excellent broadleaf for the the dry shade garden.  

However, the true, pureblooded wild manzanitas are harder to tame. Because:
They generally dislike clay, I feel, because it is most apt to drown or lethally dry them.  In my experience of planting literally hundreds, I think that a sandy, or even silty soil is nearly required to grow these. (There are exceptions, but they are super rare) My observation is backed up by the fact that the species we are trying to grow are (almost) never in clay in nature.

So if you are truly constructively lusty for this plant, dig out and replace your planting bed or pile up some great mounds of sand-based or sandy soil.  They even like a bit of compost/organics.

It makes things more complicated that manzanitas rely on a symbiotic root-fungus (mycorrhizae) to thrive, and it's been shown that chemical fertilizers are detrimental to the fungus.  Where can you get the right type of mycorrhizae for your plant other than grabbing a pinch from under a plant in nature?
I don't know.


Arctostaphylos patula in nature; Glade Park, CO. A "true" manzanita.



The odd botanical background to Manzanitas is that they are epicenter-ed in California, where they are most diverse, and are in the rhododendron family, so the charisma of these understated beasts in their cheery pink or white late-winter flowers and their voluptuous red bark under those thick evergreen leaves is what lures a great following of us who are prepared to go great lengths to have them in our gardens.

Ironically, once established, they are zero maintenance.   Zero.  
Arctostaphylos patula at the APEX crevice garden.


Our Tricks:

We have successfully established manzanitas with a good (80-95%) success rate in recent years by:
-Planting healthy, well-fed (fertilized) plants (#1 "gallons" or 4" pots) in anytime but summer (Oct to April.)  Manzanitas, although green, appear to be dormant for the summer and often die if planted then.
-In a sandy soil, or sand-based artificial soil mound/bed.  North or east exposures are ideal, others will do.
-Water moderately to establish (soaking every 2 weeks -ish)
-Not fertilizing once in ground, but putting in a handful of wild soil, hoping to introduce the mycorrhizae. (I have no scientific proof for this and have yet to do a side-by-side trial without)
-And knowing once the plant has put on good shoot growth in 1-2 seasons, it is established and apt to be there for good.

Here's to your success.

Tuesday, February 7, 2017

Crevice Gardens of the Future


The culture expands, the craze continues.  I guess it is bucking the definition of a fad, rooting deeper while it expands in complexity.  Folks around the world are trying new things with crevice gardens right this moment, and here are a few fresh projects that I am aware of in North America.

Enjoy some previews of gardens-in-the-making which will surely be known in articles, books, blogs, and lectures in future years.




Yaro Horachek in Calgary, Canada with a natural predisposition of crevice gardening in his Czech blood, is working on his new crevice section. It makes good use of a moist north slope and incorporates tufa stone pieces as well.  His life as a geologist means that he will certainly also join the big experiments of artificial soils and have some results in time to share with the world.

The Czechs, as many are aware, are the historical nexus of the development of crevice gardening which elevated and lithified it into a timeless art form.  That nexus will be pulsing its influence into the world again at the 3rd Czech International Rock Garden Conference in Prague in May, where piles of internationals including myself will bask in the glow of the masters. We will take home, to our proper places world-wide, knowledge and inspiration like so many affectionate seeds.






Susan Sims, whom repeat readers will know as Susan-in-the-pink-hat, in Orem, Utah (Near Salt Lake) doesn't do anything half-heartedly, so her stewing designs to use this tumbled local Utah limestone in a naturalistic diagonal-strata is sure to rock our world.

 She has been gathering inspiration and data from every rock-garden expert she can find. With her incredible natural art and design talent, I wait with bated breath.

Pressure's on, Sims.







 Diagonal orientation is not new.  The earliest examples of this in Colorado have at once been long-time inspirations for us and also trials where we learned, it seems to me, that especially clay-based soils can be crushed under leaning rocks as they settle, reducing the good interior drainage of the soil. (Although surface drainage and rain accumulation effects still work).    This is because most of the rocks don't touch one another.

John Lawyer (left) in Colorado Springs has a solution; all of his leaning rocks are supported by other rocks, so big gaps are laterally between smaller, supportive "struts" or "shims" if you will.  This leaves a variety of tiny to generous gaps between the stones for big and small plants.  The key is that the rocks all touch one another.  It takes more rocks, but he's growing things much better in this situation, including paintbrush. (Castilleja integra)




Not to be left out, I had to re-visit diagonalism using Mr. Lawyer's tricks in 2016.  But additionally, mine also plays with a formal Blue grama meadow-strip in front, no irrigation, and a passive-rainwater harvesting earth-basin behind it, fed from a very large roof, which it's south-facing slope returns down into, creating a microclimate I've never seen before. What will we call it? Seasonally-wet-but-unirrigated-crevice?  What on earth will grow in there?  Festuca ovina for a start.










Frankly, diagonal construction like this is much harder, slower, and admittedly frustrating to build for a vertical classic-czech-school ingrained student like myself.  But we much branch out, and I cannot resist the fact that all of our local natural outcrops in Western Colorado are diagonal and eroded like this.

Of course, the plants we're trying at the Rauch house are the exciting icing on the rocky cake.


Zinnia acerosa is a perennial desert Zinnia (but in white!) like the above mass of gold Zinnia grandiflora, and we are trying it for hardiness.  It loved the summer and has overwintered in this very mild winter, despite the seeds being collected from under a Saguaro outside of Tucson, AZ.  I have seed from colder places to try, too.


We've also got a small herd of the improbably colourful Manfreda maculosa, and a single native perennial sensitive-plant, Schrankia nuttalii,  in trail.  Stay tuned for results for those.

Now for big fish.



Jeremy Schmidt creates the Crevice Garden at Juniper Level/Plant Delights Nursery in Raleigh, NC.

Many are aware of what is probably America's most serious current hardcore plant-nut mailorder nursery, the only one-X rated plant catalogue I've ever seen, and they offer incredibly healthy plants of incredible species you truly can't get elsewhere.  How about a corpse-flower? No, not the little 4' one I grow and bloomed, but the king-daddy.  Yes, they sell that.  They revolutionised my garden and blew my mind as a teenager, and my teen-ager-planted garden still has little palm trees (in Colorado, yes) in it thanks to them.  (For your irrigated, guilty-pleasure garden, zone 5 and warmer, the hardiest is the needle palm!)

Plant Delights is Tony Avent's brainchild, which spawned their own Juniper Level Botanic Garden.   They have a small rock garden and being some of the craziest plant nuts anywhere, it was only a matter of time before they built a crevice garden.



Jeremy Schmidt is using some 50 tons of concrete, salvaged from a barn they razed at the nursery.  This garden wil be incredibly important as the flagship of crevice garden experiments in the southeastern United States.  I started a small crevice garden there in Raleigh at the venerable J.C. Raulston, Arboretum there in Raleigh, NC, but Plant Delights will have a massive space for their massive brains to test the catches from their massive dragnets of botanical curiosity.

They specialise in many genera, including agaves, and agaves are more often-than-not natural crevice-dwellers.




We should all be really jazzed to see what these whackoes pull off.  I'm particularly excited because:
1. The function/effect of crevice gardens needs to be tried in more climates, and
2. They will find more weird plants to try than anyone else, and
3. Let's see more recycled concrete gardens ("urbanite" as some are calling it) - which I knew I was unlikely to do myself.  I think it actually honours the genius loci of places where big, bold, busty, natural rocks are not such a common part of the daily vista.  It holds a big future for urban/city crevice gardens...






That bill is getting filled.

-Filled with experimental soil mixes, including their local expanded shale product, Perma-Till, because Jeremy can't help but deploy his deep knowledge of soil science.



Now, recycled concrete crevice gardens have famously been done before at the Utrecht Botanic Gardens in Holland. (Winter picture courtesy of Malcolm McGregor. )  The builders of these fantastical spheres used scoria in the soil mix between the layers to keep the soil from being totally crushed by the slabs.




(Picture, right, also courtesy of Malcolm McGregor)



Let's go back to Colorado.

And finally, I'm excited about the modern aesthetic's influence in crevice gardens.  Above, the gumball-coloured "Cherokee" sandstone  of the garden-in-process looks totally at home next to this new family house in Fort Collins, CO.  (Laura Shaffer/Kenton Seth design) The first picture on this post is that incredible stone, which somehow manages to naturally have bits of the bright colours that match the house.  Well played, Laura!  She says Agave utahensis ssp. kaibabensis looks to have overwintered there. 

(To come: a big batty blog, where I opine and agree with High Country Gardens that it is the hardiest of all agaves. This conclusion after many long walks, old books read, long hikes, many half-guiltful tanks of gas, winter camp-sites, strange animals, and few showers.)

Happy early early spring 2017, friends.