June 5, 2026
The gardens I visit in Colorado seem to have several of these pots. It has rugged, stone-like grooves in shades of gray and pinkish-red, some of which are horizontally raised like sedimentary layers. When I ask, gardeners always say, “Oh, Domenic Turnbull makes them.” It’s chock-full of mountain-like rocks and small alpine plants and succulents, which to me epitomize the Colorado aesthetic.
Naturally, I decided I needed to have some for myself too.
So, being myself, I invited Domenic to his garden. And he readily agreed. Plan a Front Range road trip to Green Mountain Falls, about two hours south of Denver.
tufa valley
Domenic is a master of hypertufa. For years, he made pots to sell at gardening events and plant sales around the state. Rock gardeners and crevice gardeners snapped them up. Hypertufa is cold hardy, reminiscent of the Rocky Mountains, and is also great for plants that require good drainage. (For those of you who don’t know about hypertufa, neither did I, here’s a book review by a plant expert about hypertufa gardening.)
But the days of bringing tufa pots to events are over, Domenic said. In fact, he only has a small amount of money left to sell. Hey, I’m glad I got there before everyone else left! I bought the large dark gray one pictured above and several smaller ones in various shapes. They will be the first part of my new garden.
A few large ones remain.
Now, let’s visit Domenic’s garden, which is nestled quietly on a green mountainside. There are many gap gardens.
Czech-style niche garden
I counted at least seven niche gardens around Domenic’s red-framed house, each built with a different type of stone. He calls it a Czech-style niche garden, where the stones are placed close together. Creeping and mounded plants keep a low profile, and by the end of May there were lots of flowers.
tufa tower
Nearby, the Tufa Tower (Domenic calls it the Tufa Wall) steals the view.
The 6-foot-tall tuff tower is a cliff-like habitat for alpine plants, including a small pine crest.
There’s no soil. Domenic makes a pocket-sized hole in the rock and squeezes a small plant into it.
Bent wire mesh will protect your new plants from birds until they are anchored to the rocks.
Since there is no soil, the plants must be watered daily. This surprised me. Domenic uses an irrigation system to automate daily watering.
Gardening with bare rocks is a great skill.
red rock crevice garden
A garden in a crevice of red rocks between the street and the greenhouse is dotted with green cushions and thorny cacti.
The Indian paintbrush reminded me of spring in Texas, but the pink-flowered cat was new to me.
The latest gap garden
The brand new crevice garden with a winding path down the middle is newly planted but still mostly shaky to my untrained eye. However, the rocks were impressive, with some blocky rocks, and must have been difficult to locate.
On one side, there is a briquette-like block of stone in a tufa valley. I think Domenic is both a gardener and a rock hound.
The rocks look like miniature mountain ranges or lava fields.
further valley
The foundation at the back of the house is lined with cactus grooves. Notice how Domenic cleverly lifts parts of the valley to create a staggered display.
The largest is as long as a loveseat and is made of old, weathered tree trunks held in place with cement.
gray stone niche garden
Nearby, pink-speckled rocks lead the eye to a gently undulating crevice garden.
It was a large thing made of round gray stones, and looked like a river bed.
Fresh greenery was sprouting from the gaps. Other than the artistry of the rocks and plants, I didn’t notice any art in Domenic’s garden, except for some bird art here and there.
Domenic said he felt the birds were a natural part of the garden. I agree.
Daphne made the garden smell sweet.
Purple bellflowers look beautiful against the gray rocks
pine tree candle
The oldest gap garden
His oldest crevice gardens roam along roads, with mountain slopes in the background.
I love this weeping Norway spruce, its hairy cousin It. Domenic is training himself to crawl on upright rocks.
Broken concrete gap garden
Another type of niche garden is made of concrete debris and is also called urbanite.
As Domenic pointed out, recycling old concrete in this way saves material going to landfills, and it works just like stone.
See more of his planters
trough garden
The showiest of his trough gardens, at the end of his driveway, is a large collection of tufa planters, each with its own rock and plant ecosystem.
I love how the crevice planters bring the mountain landscape to a human scale.
Gap planter with bird
If you tilt a broken pot to the side, you can see striped rocks and plants that like crevices.
This red trough has a wall in the back corner that provides vertical planting space.
The pipes and concrete slabs make the valley look beautiful and prevent hypertufa from freezing and damaging the ground in winter.
Another beautiful valley with spring flowers
birds and rocks
moss gap planter
We offer moss crevice planters that are bathed in the occasional splash of water from a rock fountain.
It was so fun to see how Domenic transformed his passion for tufa valleys, alpine plants, and crevice gardening into a landscape that blends well with his mountain home.
If you’d like to learn more about Domenic’s Gardens, check out this video tour I found online.
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My new book, Gardens of Texas: Visions of Resilience from the Lone Star State, has been published. Available at Amazon, other online book retailers, and stores nationwide. Fun for anyone who loves gardens and the natural beauty of Texas. Click here for more information.
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