It’s no secret that the intermountain west had a rough winter (warmer than normal, little snow). This now has many of us worried about drought and fire, which a lot of us kind of always worry about, but this year even more so. Of course, the dry conditions impact birds, pollinators, and wildlife as well. Not only do they need water to drink, but the plants that they rely on for food and to serve as host plants are impacted by drought as well. Blooms are smaller and contain less pollen and nectar and bloom times can also be earlier than usual so that by the time pollinators look for them to lay eggs on them or feed, those plants are no longer available (more info at pollinator.org and at the Xerces Society). And if the pollinators are struggling, that means there are fewer caterpillars for birds to eat and feed to their young.
But even though we had very little water and it’s super hot, it’s still important (and totally possible!) to start a little garden that adds another little patch of habitat for our struggling critters.
So, we just planted a new dry, rock garden area and we’re pretty excited about it! With one exception, these are all plants that we started ourselves from seed. They were watered when planted, and then about once a week until some rains started happening. Once established, we intend to give these plants little to no supplemental water. This space is at the nursery and visitors are encouraged to take a look. We are happy to talk with you about these plants, their benefits, and the challenges we face with growing them in our clay soil.
Dry Garden Goals:
- Create a diverse habitat for birds, pollinators, and wildlife (by planting multiples of a variety of plants with a range of bloom times and by including non-plant habitat elements such as logs and rocks),
- Build soil (native plants have extensive root systems which add organic matter and contribute to the soil microbiology),
- Learn more (always! Gardens are like laboratories) about these fascinating plants the wildlife they attract (by working with the plants and through observation),
- Grow a demonstration garden that features low water, native plants that others might want to grow, and
- Establish mother plants for seed collection.
The Space: We are located in western Colorado at about 6500 feet in elevation. The nursery is about ⅓ acre on an exposed, southwest-facing slope with deer fencing. Within that, the dry garden is pretty small, about 10’ x 30’. It gets very hot and it gets hit pretty hard by wind. The soil is heavy clay and rocky. It seems to drain very well in the summer thanks to the slope and the wind. However, our soils hold a lot of moisture in the winter time, which was a concern for us because many low water natives require soil that drains well. The surrounding land is juniper forest with gamble oak, (the pinon pine is at a higher elevation), and shrubs such as antelope bitterbrush, big sagebrush, Utah serviceberry, and others. This area was cleared for agriculture long before our arrival.
The Prep: A year and a half ago, this entire area was covered in aggressive, non-native grasses that spread through rhizomes. Great for pasture, but very challenging if you want to plant anything else. We began by laying down silage tarps about a year ago. We needed a way to injure/slow the grass down enough so that we could plant. The intent was to allow the plants some time to get established and keep it manageable so two people could weed by hand (our preferred method). Tarp was laid on almost ⅓ of an acre and we are slowly pulling it back to plant various areas.
Many people use herbicides for this when doing broad/large scale invasive species removal and habitat creation. However, we are adamantly opposed to using these for many reasons, so that was not an option for us. Tarping is not perfect, but for us it was the solution that fit best. Fingers crossed that it works. We will find out how successful this was in time as we start putting water on the area.
The Planting: We planted in late June. To improve drainage, we added red lava rock and some woodsy compost to the native soil that we dug out of the planting holes. We added that mixture back in around the plants’ rootballs. In addition to helping with drainage, the compost could also, we hoped, help bring some microbial life back to the soil after being tarped for a year. (We believe that our ditch irrigation water will also help with this.) The light weight, porous lava rock was a great discovery that we learned about from our local Earth Friendly farm supply store (thank you!!!). It is affordable and readily available on the western slope (unlike expanded shale, which is often recommended). After planting, no additional soil amendments will be added.
The Plants:
Pale Wolfberry/Pale Desert Thorn (Lycium pallidum) Benefits: Thorny shrub related to goji berry provides excellent shelter and food (berries) for birds and other wildlife. Early summer blooms attract native bees and butterflies.
Palmer’s Penstemon (Penstemon palmeri) Benefits: Provides nectar for bumblebees, hummingbirds, and possibly moths as well. We are north of its native range and it is known for growing in sandy, rocky, and very dry soil. Growing this in our location and clay soil is an experiment. So far it is growing very well!
Big Sagebrush (Artemisia tridentata) Benefits (in our garden): Cover and nesting sites for birds. Late summer blooms for native bees. Nest material for native bees. Soil health. Ecological restoration. Host plant for the Hera Buckmoth and likely many others.
Sideoats grama (Bouteloua curtipendula) Benefits: Provides shelter and seeds for birds. Larval host and food source for caterpillars.
Indian Ricegrass (Achnatherum hymenoides) Benefits: Seeds for birds and small mammals. Larval host for skipper butterflies. Grows wild in our native rocky, clay soil. Highly drought tolerant.
Fourwing saltbush (Atriplex canescens) Benefits: Large woody shrub that grows fairly quickly. Provides shelter for wildlife, nectar for pollinators, host plant for at least 14 species of butterfly and moth caterpillars including several that specialize on Atriplex sp., and food (seeds) for birds and small mammals.
Prince’s Plume (Stanleya pinnata) Benefits: Very showy and long-lasting spring blooms, nectar for a wide range of pollinators (including native bees, butterflies, moths, and hummingbirds), host plant.
Bridges Penstemon (Penstemon rostriflorus) Benefits: Long, tubular, red flowers combined with a long,mid-summer bloom period results in an excellent nectar source for hummingbirds. Also a great choice for supporting native bees. Extremely drought tolerant.
These are the only plants in this garden that we did not grow ourselves. These plants were a gift from a friend. Thank you, friend, for the plants and for turning us on to this super cool penstemon! We definitely hope to grow this variety in the future.
Winterfat (Krascheninnikovia lanata) Benefits: Shelter and food for birds and small mammals. Important, highly nutritious winter forage for elk, mule deer, antelope, and bighorn sheep. (This won’t happen in our fenced area, but it is definitely an important feature of this plant in open landscapes.) Erosion control. Reclamation. This one is for birds and small mammals in our setting. Not really a plant for pollinators, but it helps create a healthy habitat over all. One of our favorite shrubs due to its visual interest.
Tenpetal Blazingstar (Mentzelia decapetala) Benefits: Night bloomer that attracts bumblebees and sphinx moths. Short-lived. We very much enjoy these plants. Looking forward to learning how this grows in our well-drained clay soil and if it will reseed. So far it is growing quickly!
Fringed Sage (Artemisia frigida) Benefits: Late summer/early fall blooms for native bees. Artemisia sp. are important host plants. This is a xeric garden favorite, so far growing well in our clay soil.
A few other good choices for native, dry/rock gardens in the intermountain west are:
- Wild/Desert four o’clock (we’ll have a few available this fall)
- Any penstemon
- Old field (gray) goldenrod
- Western wallflower
- Apache plume
- Dotted gayfeather
- Mountain mahogany
- Spanish bayonet yucca (which we are growing for next year) or other yuccas
- Native cacti
- And certainly many others!
We are really looking forward to seeing how this garden plot evolves. We will no doubt be adding some of these additional plants and learning as they all grow and become a more mature habitat. Fingers crossed for long, gentle, late summer rains (not extreme torrents and floods) as irrigation ditches are shut off. And we will hope for a healthy snow pack this winter.
Thanks for gardening in a way that gives back to the earth!
