Design the Ultimate Xeriscape: Mix Perennials and Cacti
New Mexico is rich with cold-hardy cacti species, having more species than almost any place in the Western Hemisphere. And we can use these incredible wildflowers to enrich our northern NM xeriscapes with brilliant flowers, sculptural stems and ornamental spination. It’s essential that we integrate cacti with other perennials, grasses and succulents to duplicate how they live in nature with many other plant types. Relegating cacti to just a pincushion grouping in an unused corner of your landscape deprives you of their true beauty.
Echinocereus engelmani v variegatus Stachys inflata, Alyssum
Cacti are Essential Early Season Natural Nectar for Native Pollinators
Not only do cold-hardy cacti bring a fascinating botanical element to your xeric garden, but they are tremendously important nectar sources for pollinating insects early in the spring before other plants bloom. Take the time to observe your cacti in flower and you will see the flowers alive with all types, sizes and colors of native bees and tiny pollinating wasps.
Penstemon pinifolius, Echinocereus, Agave utahensis, Hymenoxys
Creating a Cactus Berm
Cacti and other xeric plants like a fast-draining soil and benefit from being planted on a raised mound of soil (also called a “berm”) with rocks strategically placed top to bottom that provide planting pockets between them. Find a sunny spot (some afternoon shade is OK) to locate the berm.
Then, mix the garden soil where you’re locating the berm with white pumice (available locally from several soil yards), Yum Yum Mix and Reunity Resources compost.
Mix two parts garden soil mixed with one part pumice.
Add a cup of both Yum Yum Mix and compost, per 5-gallon bucket of pumice and soil.
Once mixed, mound the soil mixture and artfully place some lichen rock or river rounds in a natural-looking arrangement prior to planting.
Planting a Larger Cactus Garden
The design of a planting that includes cacti can also be on a larger scale, planted into flat or sloped ground. Here, big growing barrel and pad type cacti combined with other larger xeric plants to create low water, low maintenance designs.
When planting the cacti into flat ground, mix the pumice, Yum Yum Mix and Reunity Resourses compost, at the rates listed above, into the cactus planting hole. All the other plants don’t need the extra drainage (pumice) but will benefit from the use of compost and Yum Yum Mix into their planting holes at recommended rates.
Use Crushed Gravel Mulch When Planting is Completed
After the planting is done, mulch the whole berm or flat area with small 3/8” to ½” crushed gray or Santa Fe brown gravel to a depth of 1 to 2 inches. This is essential as it helps to make the plants and cacti grow better and faster while facilitating watering by helping the water soak into the soil and not simply run off downhill.
gravel mulch (left) with Echinocereus triglochidiatus, Scutellaria, Hymenoxys
Large Growing Cacti
Here is a shortlist of large growing cacti to create larger plantings that cover more square footage.
Echinocereus coccineus (Needle Spined Claret Cup),
Echinocereus triglochidiatus (Claret Cup),
Opuntia engelmannii ‘Inermis’ and
various Cholla species (Cylindropuntia).
Unfortunately, there are no commonly available cold hardy column types (i.e. Saguaro) or tree type Opuntia that are seen in warm winter deserts around Phoenix and Tucson. Instead, we can use the large succulents listed below in their place.
These Large Growing Succulents that provide some height in the plantings include;
Large Agave (Agave parryi, Agave neomexicana, Agave havardiana and Agave palmeri)
Yucca (Yucca faxoniana, Yucca torreyi, Yucca elata, Yucca baccata and others)
Hesperaloe parviflora (TX Yucca)
Penstemon, Echiinocereus rigidissimus, Yucca nana hybrid, Echinocereus chloranthus v. weedenii
Add right sized Xeric Native Shrubs that should also be included in the cactus/succulent mix include;
Prunus besseyi Pawnee Buttes® (Creeping Sand Cherry)
Fendleri rupicola (Fendler’s Cliffbush)
Cercocarpus intricatus (Littleleaf Mountain Mahogany)
Fraxinus cuspidate (Fragrant Ash)
Prunus andersonii (Desert Peach)
Salvia dorrii (Great Basin Sage)
Salvia pachyphylla (Giant Mojave Sage)
Chrysothamnus nauseosus ‘Baby Blue’ (Dwarf Rabbit Brush)
Amorpha nana (Dwarf Leadplant)
Amorpha canescens (Leadplant)
Salvia dorrii v. incana 'Robusta', Pinus syvestris 'Compacta', Hesperaloe parviflora
Xeric Perennials and Ornamental Grasses Add the Icing to the Cake
Interplanting cacti with xeric perennials and ornamental grasses helps gardeners replicate what we see in nature where cacti grow with other wildflowers. They are good companions for each other and add additional flowers for pollinators to feed on. When shopping for companion perennials, look for plants that are xeric, like full sun good drainage. Some of the best xeric perennials include;
Hymenoxys (Sundancer Daisy)
Engelmannia peristinia (Engelmann Daisy)
Agastache rupestris (Licorice Mint Hyssop)
Salvia greggii (Texas Bush Sage) – many different cultivars
Echinocereus triglochidiatus, Agastache aurantiaca, Agastache hybrid
© All articles are copyrighted by WATERWISE Gardening, LLC.
Republishing an entire WATERWISE Gardening blog post or article is prohibited without written permission. Please feel free to share a short excerpt with a link back to the article on social media websites, such as Facebook.