The amount of water needed and where that water should be applied changes as woody plants (such as trees, shrubs and vines) get larger. Woody plant material has two types of roots, stabilizing roots and feeder roots. Both types of roots do just what their name implies. Stabilizing roots are thick and dense to keep the plant in place and support its weight. Feeder roots are super fine and grow more like a net to take in water and nutrients. Feeder roots expand out as the plant grows.
Some woody plants require more water as they mature, but more desert-friendly species may not require extra water or may even be able to survive without supplemental irrigation once established. Perennials normally do not need to have expanded watering the same way woody plants do as they mature.
Some examples of this:
Plant Type
Plant
1st summer
2nd summer
3rd summer
Tree
Desert Willow (Chilopsis linearis)
60 gallon per month
120 gallons per month
400 gallons per month
Shrub
Butterfly Bush (Buddleia davidii)
60 gallon per month
70 gallon per month
100 gallon per month
Desert-Friendly Shrub
Chamisa (Ericameria nauseosa)
20-30 gallons per month
20-30 gallons per month
Usually possible to remove from irrigation
Vine
Trumpet Vine (Campsis radicans)
40 gallons per month
60 gallons per month
100 gallons per month
Woody Groundcover
Prostrate Sumac (Rhus trilobata)
20-30 gallons per month
40 gallons per month
60 gallons per month
For those plants that do have increased irrigation needs as they mature here are three easy ways to apply the right amount of water in the right place depending on the type of irrigation you are using.
Drip Emitters – Move the drip emitters out to stay in line with the outer edge of the plants leaves where the feeder roots will be. Increase the number of emitters watering the plant too, placing them evenly around the outer perimeter of the plant.
Netafim (in-line professional drip line) – this is typically installed in rings around the plant and additional rings can be added as the plant grows larger. Netafim can also be laid out in a grid pattern, particularly when being installed around an already established plant.
Hand-watering – Build and maintain a watering well at the outer edge of the plant perimeter. As the plant grows, increase the size of the well.
Author: Richard Perce, Irrigation Efficiency Specialist with the Water Resources Division for the Water Authority. Have a question about the article AskAnExpert@abcwua.org
Shredded woodchip mulch helps soil hold moisture and insulates plant roots on a frosty November morning. Photo credit M. Thompson.
One of the most frequent questions we get at NMSU Extension is, “Should I add fertilizer or amendments to the soil when planting?” The short answer is no. And the long-term answer is an even stronger no.
Soil amendments are materials that are
worked into the soil with the intention of improving soil physical qualities. But
it’s just not that simple. As City of Las Cruces Community Forester Jimmy
Zabriskie said when I asked if he ever recommends using soil amendments when
planting a tree, “Save your money for mulch.” Organic
mulch is
material that sits on top of the soil, providing an insulation layer that helps
control soil temperature, retain moisture, and suppress weeds.
When planting ornamental plants, the
recommended species are the ones with roots that are well adapted to our native
soils. They’re more likely to live long, sustainable lives in our native soils
without amendments. The bottom line: Always put the same soil you dug up right
back into the hole with the new plant, and top dress with a thick layer of
mulch.
Frosty cottonwood leaves add a nice layer on top of several inches of shredded woodchip mulch. Photo credit M. Thompson
As for fertilizers, slow and steady wins this race. As Albuquerque City Forester Joran Viers said recently at a tree planting demo put on by Tree New Mexico and The Nature Conservancy, it helps to think of our trees (and other plants) as marathoners, not sprinters. When fertilizer is applied to trees, they can grow too fast for their own good and are more likely to develop structural problems and other issues. Fertilizers are not recommended at the time of planting perennial plants, either, because we want the plant’s energy to go into root establishment at a healthy rate to support the aboveground growth. The growth hormones necessary for healthy root development are found in the root tips and are made by the plant itself, so adding root stimulator to living roots is not necessary or even helpful. (Side note: Rooting hormone is potentially useful when you’re trying to get roots to grow quickly from cuttings where the roots have been removed completely.) So hold off on fertilizing for at least a few years while your plants are setting down roots.
Research on all sorts of landscape plants has shown that by adding amendments (like organic matter or perlite) to your soil backfill, the initial, short-term results are good. But the interface between the amended soil and the native soil is bad news. Water doesn’t move well across the interface, and neither do roots. With time, the roots may be inclined to stay in the original planting hole and spiral around, so you end up with essentially a potted tree or plant with reduced growth rate, constant water and nutrient stress (because lateral roots never fully developed), heightened vulnerability to pests and diseases, and even an increased falling hazard (think root ball in socket).
Author: Marisa Thompson, PhD, is the Extension Horticulture Specialist for New Mexico State University and is based at the Agricultural Science Center at Los Lunas. For more gardening information, including decades of archived Southwest Yard & Garden weekly columns, visit the NMSU Extension Horticulture page (https://desertblooms.nmsu.edu/), , follow us on social media (@NMDesertBlooms), or contact your County Cooperative Extension office (https://aces.nmsu.edu/county).
Have you ever wished you could
just take a picture of a plant and have the internet identify it for you? Turns
out, there are a lot of digital options to help with the identification of
plants. We’ve reviewed the best resources so you don’t have to.
PLANT APPS:
iNaturalist: Once logged on to this free application, you become one of their citizen scientists. The app uses your photos then provides you with a list of possible plant choices. Once the plant has been identified the app then asks you to upload the data to help other people learn what’s in their neighborhood (there is the option to skip this and just get the plant identified). This app was by far the best at identifying the correct plant. An added bonus is it allows users to create guides and gives access to others created in the area. In fact, there is a fantastic Plants of the Middle Rio Grande Bosque guide already on the app listing hundreds of plants in the Albuquerque area.
Pl@ntNet: This free app uses a database organized by location to identify plants. Simply upload a photo and the app provides a long list of possible matches. It’s common to find the correct plant among the choices given, but if a match is not made, users may access the world flora database to find the exact plant. This app is good at identifying the plant family which is a good start in finding the right identification. The best attributes of this app are that it does not require a login or account and you can either take live photos or select from your photo library.
New Mexico Wildflowers. This free, local app is a winner - it’s basically an online field guide boasting more than 3,000 local plants! Select a plant type, flower color, flower size, leaf arrangement and habitat. It then provides a list of plants that meet the criteria. From there, users can identify the plant in question. A great feature of this app is that it can be used during your favorite outdoor activity because internet access is not required.
New Mexico Wildflowers app
iNaturalist app
LOCAL DATABASE AND GROUPS:
New Mexico Plant List Database: This plant database is courtesy of the Office of the State Engineer. It has a large variety of plants with an easy-to-use interface. https://wuc.ose.state.nm.us/Plants/
Groups: Another way to figure out plant identification is to crowdsource using social media. There are a few notable Facebook groups that regularly answer plant ID questions, where members upload photos of the plant with location details, and members of the group provide input. A few to check out are Native Plants of New Mexico (4,027 members), Entomology (135,034 members), Plant Identification (174,670 members), and Plant Identification and Discussion (278,523 members).
Other apps: PlantSnap, Picture
This Plants, Seek. We’ve found these to be less reliable for identifying desert
friendly plants.
TIP: When using any of these tools, the quality of the photo is important. It’s helpful to have both zoomed-in pictures of foliage and photos of the entire plant form.
Author: Marisa Y. Thompson, Ph.D. Extension Horticulture Specialist, Department of Extension Plant Sciences NMSU Desert Blooms blog and Jill Brown, ASLA Landscape Architect and owner of My Landscape Coach in Albuquerque, NM. Resources: Native Plants of New Mexico Facebook Group
When we think of the word evergreen, many of us think about pine trees, cedars and junipers. However, an evergreen is simply any plant that remains green all year long. These plants are welcome fixtures in our winter landscapes, too. 505Outside highlights these essential elements of the greater Albuquerque area landscape by asking local plant experts which ones they love. Below are some of their favorites.
When the last of the yellow and purple perennial colors fade away in the fall, these (and other) evergreen plants provide the structure that holds landscapes together through the winter months. Don’t forget to include evergreen plants in your landscape for year-round interest.
Now that the weather is colder, curl up with a book and
learn more about our global and local water resources.
Here are a few of my favorites to get you started. If you’ve
got a water book to recommend for future newsletters, please email me at kyuhas@abcwua.org
For a thought-provoking read about the effect of rising sea
levels throughout the world, pick up The Water Will Come: Rising Seas,
Sinking Cities And The Remaking Of The Civilized World by Jeff Goddell. He
uses a blend of science and first-person accounts to create an engaging and
informative read. This book made many top book lists when it was released in
2017.
Replenish: The Virtuous Cycle of Water and Prosperity by
Sandra Postel explores many projects, including some in New Mexico, that work
with nature to enhance and preserve the earth’s water resources. Ms. Postel is
a world-renowned water expert we’re lucky to have living with us here in New
Mexico.
Another New Mexico book is A Song for the River by
Philip Connors. This is beautiful, meditative exploration of his time in the
Gila National Forest and of the Gila River. Those who want more of Mr. Connors’
writing on the Southwest should also pick up the multiple award-winning Fire
Season: Field Notes from a Wilderness Lookout.
Finally, for those who want to get started dreaming about their
spring garden, try Growing the Southwest Garden: Regional Ornamental
Gardening or any of the other gorgeous, picture-laden titles by Judith
Phillips, another author we are lucky to call our own. Her beautiful books can
be found at local bookstores and libraries.
Author: Katherine Yuhas, Water Resources Division Manager with Albuquerque Bernalillo Water Utility Authority
One of the
great advantages of desert-adapted plants is the wealth of colorful flowers
they produce, a boon to gardeners and pollinators alike. Plants that bloom in
autumn offer pollen and nectar for insects and, if the seed heads are left to
ripen, a late season food source for birds.
After a long hot summer, some plants think the cool of fall means it’s spring again and burst into bloom with renewed vibrance. Salvia greggii is commonly called autumn sage because, even though it flowers brilliantly in spring and lightly all summer, fall brings on another strong show. Responding to the cooler, longer nights in autumn, Salvia’s late season color becomes even more intense. Autumn sage is a compact shrub that grows 2-feet tall and 3-feet wide, with small dark green leaves and spikes of flowers in red, rose pink, coral, purple or white. Hummingbirds and bees are frequent visitors. Autumn sage prefers well-drained soil and deep watering (24 to 30 inches) every week or two while blooming, monthly or less in winter.
Autumn sage, Salvia greggii
Many ornamental grasses are their showiest in autumn, too. There are several varieties of little bluestem Schizachryium scoparium with 12-inch wide clumps of narrow blue-green leaves and 24-inch tall slender stems bearing fuzzy seed heads. ‘Blaze’ little bluestem turns scarlet in fall and ‘The Blues’ turns a beautiful pink. Both keep their color into winter when they fade to a rich bronzy brown. The color is our reward for supplying the little extra water these grasses need.
Native grasses are also important larval food for butterflies and produce nutritious seeds for songbirds, bringing color on wings to the garden. Since the seed heads are a large part of the reason they are planted, ornamental grasses should be left uncut until early spring. Then, trim them a few inches from the ground so the new growth is not stymied by having to push through old stubble to reach sunlight.
Little bluestem Schizachryium scoparium
Perhaps the most spectacular late blooming perennial is the Maximilian sunflower Helianthus maximiliani. By early autumn, its flower stems are 5 to 7-feet tall. Established plants can spread 4 or more feet wide, shooting up dozens of flower stems. The top few feet of the stems are covered in 2-inch wide yellow sunflowers with yellow centers abuzz with bees. The show can last for several weeks in September or October, but after the flowers fade the plants become a bird buffet of seeds well into winter. Maximilian sunflowers grow best in soils that hold water well and produce the best show when watered to a depth of 2 feet weekly during the growing season, every two weeks in spring and fall and monthly or less in winter.
Maximilian sunflower, Helianthus maximiliani
Flowers aren’t the only source of fall color, either, but red leaves in fall are not the norm in New Mexico. Cottonwoods in the Bosque and aspens in the mountains are our autumn gold. Chinese pistache Pistacia chinensis has become one of the most dependable heat and drought tolerant shade trees and adds splashes of red fall foliage in the ABQ metro area. A great shade tree that is 20 to 30-feet tall at maturity with a canopy spread of 20-feet, Chinese pistache benefits from structural pruning while it is young to assure strong branching. Once well rooted, it should be watered at the edge of the branch canopy to a depth of 2 to 3 feet every few weeks during the growing season and monthly or less depending on winter moisture.
Chinese pistache, Pistacia chinensis
Author: Judith Phillips, owner of Design Oasis, landscape designer and garden writer with 30 years experience designing arid-adapted and native gardens in the high desert.
