Types of Mulches

Types of Mulches

Mulch is any material laid on the surface of the soil to improve growing conditions. Mulch insulates plant roots from both heat and cold, reducing moisture loss from the soil by evaporation, feeding beneficial soil microorganisms that enhance plant growth, and improving soil health. Because organic mulches were once alive, they contain essential nutrients, minerals, and energy that nourish the soil ecosystem as they decompose. An important consideration when using mulches is to skip using landscape fabric, which prevents both the rich organic matter created by decomposition from working its way back into the soil and rainwater from soaking into the soil.

Below are the basic types of locally available organic mulches that we recommend. Remember to install to a depth of 3”-4” over bare dirt.   

Wood chips: Wood chips are chipped pieces of trees. This is a long-lasting mulch that decomposes slowly over bare dirt, retains moisture, and prevents weeds. Most wood mulches available on the market are chipped flat and consistent in shape in size. These are great in areas that receive foot traffic as they compact down to a firm surface.

In areas of higher wind exposure or periodic inundation with water, use a shredded wood mulch that is more irregularly shaped and sized as the pieces will knit together better. This type of mulch can be recycled yard waste and tree trimmings as well as commercially available, locally processed wood products.

Pecan Shells: This long-lasting mulch has a nice color and good texture. It is very slow to break down into the soil. However, it attracts birds and rodents and blows in the wind unless partially cultivated into the soil. It also tends to mat together, creating a crust over the top of bare dirt.

Straw: Straw breaks down quickly so it is most useful for mulching vegetable beds where it is renewed as crops are replanted. It is a good general mulch for winter protection and can be used on paths between vegetable rows. Keep in mind that it may carry weed seed.

Pine Needles: Pine needles are a very good mulch. They are light, airy, and attractive but can be a fire hazard. These needles are safe to use as mulch around most plants, especially perennials, in your garden. Because pine needles contain high levels of resins, they repel water and decompose much more slowly than leaves from most deciduous trees. Because of their shape, they don’t become moist or compost rapidly. This makes them especially useful in areas where you will not be digging frequently. The fragrance of pine needles on sunny days is also an added benefit when they are used as garden mulch. No need to be concerned that pine needles are too acidic for use in our gardens. The added acidity, which happens slowly, is beneficial to our soils. They are very slow to compost, so they are often a better mulch than compostable material.

Other Mulches:

Bark: Large 2”-4” bark pieces are not recommended because they take too long to break down. The mulch made from bark tends to be lighter and can tend to migrate more easily. The bark is naturally water-resistant, so it has minimal value in feeding soil microorganisms and improving soil health.

Crushed Stone, Crusher Fines, or Decomposed Granite: Crusher fines come in a variety of aggregate colors. They are recommended for use as pathways and patios or as mulch under plantings for heat-loving, desert-accent plants.

Gravel Rock and Cobble: While you see these used throughout the city in landscapes, they are best used to prevent erosion on steep slopes or in swale areas. They are difficult to maintain without regular weeding or pre-emergent treatments.

Useful tips: Mulch typically packs down over time. Use a 3”-4” layer of mulch, which is about one yard of mulch per 100 square feet. “Spend an hour deepening the organic mulch and save several hours of weeding.” By Judith Phillips

Author:  Jill Brown, ASLA. Landscape Architect and Owner of My Landscape Coach  Research collected from NMSU Desert Blooms and Soilutions, LLC
Learn How to Harvest Rainwater in Your Yard

Learn How to Harvest Rainwater in Your Yard

Do you want to learn how to harvest rainwater to support a beautiful, regionally adapted, low -water-use landscape in your yard? A new video series launched in June provides instruction on how to design, install, and maintain residential-scale, passive rainwater harvesting features. In passive water harvesting, rainwater is conveyed directly to a landscaped area and infiltrated in the soil.

Landscapes that incorporate rainwater harvesting and native/drought-tolerant plants require little supplemental irrigation. Rainwater harvesting provides the deep watering that large plants like trees and shrubs need in our hot and dry climate. Capturing and infiltrating rainwater also reduces runoff that carries pollutants to the Rio Grande River.

In this series, you will learn how to construct some of the most common passive rainwater harvesting features in residential applications – basins, swales and soil sponges. The training addresses site selection, sizing basins, grading swales, installing soil sponges for enhanced infiltration and selecting plants. It is presented by four local experts on rainwater harvesting and arid-adapted gardens: Jim Brooks, Tess Houle, Judith Phillips, and Hunter Ten Broeck.

To view the training videos, go to: www.bernco.gov/rainwater.

The video series was developed through a collaboration between Bernalillo County, Ciudad Soil and Water Conservation District, and the Arid LID Coalition, and included the installation of a Rainwater Harvesting Learning Landscape at the Gutiérrez-Hubbell House History and Cultural Center. Please visit the Rainwater Harvesting Learning Landscape in person to see an example of a rainwater harvesting feature designed for our arid climate.

Author:  Steve Glass, Chair, Ciudad Soil and Water Conservation District, and Megan Marsee, Water Conservation and Resource Manager, Bernalillo County Photography: Michael Payton, Rainwater Harvesting Design. Have a question about the article? AskAnExpert@abcwua.org
Xeriscape not Zeroscape: Water-conscious landscaping can be luscious and beautiful.

Xeriscape not Zeroscape: Water-conscious landscaping can be luscious and beautiful.

ALBUQUERQUE, N.M. — By and large, New Mexican homeowners are getting the all-important message of the arid Southwest: Water is precious, and not to be wasted.

But local experts say an important piece of the story is still often lost when it comes to landscaping: Conserving water doesn’t have to mean a yard consisting of one plant surrounded by gravel.

“We’ve got to go away from that,” said Carlos Bustos, water conservation program manager for the Albuquerque Bernalillo County Water Utility Authority. “Xeriscapes are luscious, they’re beautiful, they’re abundant, they’re resilient, they’re sustainable. … We hope that 10 years from now we’re not still dealing with the idea of ‘zeroscapes.'”

Solange Serquis, of Santa Fe-based Serquis + Associates Landscape Architecture, agreed.

“I am a big believer that we all deserve aesthetic and beauty,” she said. “When you combine aesthetic and beauty to achieve something else, like passive cooling or low-consumption plants or an invitation to be outdoors, better use of … energy indoors, that’s the main thing.”

Plant selection

According to Jill Brown, a landscape architect and owner of My Landscape Coach, selecting plants tends to be a point in the landscaping process where homeowners get very engaged.


“If I go back and look at the most popular articles, the most popular things, discussions, questions that we’ve received, it’s always about plants,” said Brown, who also provides content for the water utility authority’s landscape website 505 Outside. “So people are really interested in plants and learning about plants and in that aspect of a landscape.”

For several local landscape pros, planting trees tops the list.

“That’s going to provide shade, which is going to reduce your energy bills if you put it … on the south side of the home … or the west side of the home,” Brown said.

Bustos said if a tree is well planned and well-positioned, those energy savings can be significant.

“There’s studies out there that say that if you place a tree strategically where you need to, you can save up to 25% of the energy in a typical household use,” he said, adding that tree shade helps reduce water lost by other plants nearby.

“By creating this microclimate, you can reduce the water need between 6 and 20%,” he said. “It’s always cooler in the shade.”

Serquis says planting trees adds long-term value.

“I always say planting a tree is an act of … citizenship,” she said. “Because you plant that tree today and in maybe 50 years, it’s … a heritage for the neighborhood.”

With trees as well as with smaller plants, Serquis said she’s looking for ways to passively cool living spaces – both indoors and outdoors – and selects varieties that have low water consumption.

When it comes to choosing specific plant varieties, Brown’s got a simple approach.

“Basically native plants that you buy from a local nursery are going to work in your soil,” she said. “That’s like a generalization we like to tell homeowners: Don’t over-stress about your soil. If you buy plants from a local nursery, you’ll be OK.”

Of course, there’s a caveat: Those plants and trees still have to be watered properly.

Irrigation

Brown said data and her own experience suggest that in the universe of homeowners who care about their landscaping, about half use an irrigation system of some kind, and about half are hand-watering.

Those hand-waterers, according to Brown and Bustos, should think about installing an irrigation system.

“Hand-watering is wasteful, because they’re spraying the leaves and … we need to get to the roots,” Brown said.

Those who already have an irrigation system can consider whether it’s efficient or fine-tuned enough.

Those who use spray sprinklers, for example, may consider swapping out sprayers for highly efficient models that are more available to homeowners today than in the past, often on the shelf of local irrigation supply companies, Brown said.

Homeowners can look at whether plants in their yard are being watered to the right depth, whether their irrigation system adjusts with the seasons – less water during the spring and fall than in summer – or with the weather.

Plants’ water needs also vary depending in what type of soil they’re planted – which even in the Albuquerque metro area can range widely, from sand on the West Side to clay in the valley.

Brown concedes the considerations can overwhelm homeowners.

“People really just want you to say, ‘Hey, water your landscape 20 minutes two times a week in the summer, 20 minutes once a week in the spring and fall,” Brown said.

Lawns

Serquis said when she first moved to New Mexico from Argentina, the trend was incentivizing homeowners to get rid of their lawns altogether in favor of gravel. But lawns don’t get quite such a bad rap with conservation-minded landscapers these days.

“I think there is something in between” lawn and gravel, Serquis said. “(It) depends how you look at the grass, or what type of grass – it’s not that bad. And a xeriscape with no plants, just as a reflecting surface, could be even worse” because of the heat generated.

Brown said there are types of grass that require less water – and even if homeowners want the grass “that’s at the park,” there are better ways to water it than with a spray system that throws water high in the air and risks evaporation. Bustos agreed.

“If you have a lawn and you’re enjoying it and it’s functional and you’re taking care of it, then update it,” he said. “You know, update that irrigation system. There’s technology out there that just can make things a lot more efficient.”

Mulch

Brown said mulch is an important part of landscaping in the Southwest.

“One of the biggest things people complain about are weeds in New Mexico, and a lot of that is because wherever there is bare dirt, you’re going to get weeds,” she said. “… The simplest solution and the most inexpensive solution and easy to install is 3 to 4 inches of a shredded wood chip mulch over the entire yard.”

Mulch helps soil hold in moisture and insulate plant roots, and it breaks down over time to enrich the soil. Brown said a mulch layer often means replacing expanses of gravel.

“All gravel does is produce more heat and more weeds,” she said. “Even if you have the weed cloth, the weed cloth just makes it easier to pull the weeds.”

Starting small

Bustos acknowledged the process of adapting a landscape can be daunting. He said he encourages residents to start with the “lowest investment,” which is changing behaviors. People can start following the seasonal irrigation needs of their landscape, rather than giving the same amount of water all year.

Those ready to invest some resources can take small steps like installing smart irrigation controllers, swapping out sprinkler heads and efficient nozzles – steps Bustos said can save up to 30% of water usage in some cases.

“If you really want to invest, you want to transform your yard into a desert-friendly landscape, then we got a xeriscape rebate that folks can tap into,” he said.

Brown said while her clients may be in different phases with their landscapes, they tend to share one thing in common. “Overall, in general, people in Albuquerque want to save water,” she said. “That is a no-brainer now.”

Author: Gabrielle Porter, Albuquerque Journal Business Editor. Reprinted with permission from the Albuquerque Journal.  Have a question about the article? AskAnExpert@abcwua.org
Vegetable and Herb Gardening in Small Spaces

Vegetable and Herb Gardening in Small Spaces

Growing vegetables and herbs at home in small spaces can be easy, fun, rewarding and not expensive. Here are some tips for anyone from first timer to a pro.

Start small with a raised bed, good-sized pots or containers or a small plot of ground. Good soil is the key in all of them, so do not skimp there. If you are a composter, good compost is a great addition to our native soil, which is generally alkaline and low in organic matter. If you are growing in the ground, compost added to the soil is highly recommended. Plant nurseries offer good compost in bags, and you can also purchase in bulk, from a bucket to truckloads, from composting facilities.

When planting in containers, use a potting soil labeled for growing vegetables. Do not use pure compost, topsoil or garden soil in containers. Those are designed for in-ground use. Start your own seeds or purchase plants from a local nursery.

Choose what you grow based on what you love. Most will agree there is nothing like the flavor of a homegrown tomato, but the joy of growing, harvesting, preparing, sharing and eating something you have grown is a rich pleasure in a complicated world. Beans are fast and easy to grow. Since dried beans are inexpensive and readily available and it takes a lot to make a pot of cooked beans, I stick to green beans. I have done Three Sisters (corn, beans, squash) in large pots on my patio using climbing green beans.

Tomatoes will do fine in a five-gallon pot or larger, and peppers of many varieties do great in containers, as do most herbs. Look up books on companion planting. Roses Love Garlic and Carrots Love Tomatoes are books by Louise Riotte that suggest good neighbors in the garden. Lisa Mason’s Vegetables Love Flowers and Companion Planting by Sally Roth also give useful information. I have planted borage with my tomatoes for many years on the advice of an old gardener friend, and I rarely have tomato worms. Borage is both beautiful and edible!

Never leave the surface of the soil exposed. Always use mulch. My preferred mulch is barley straw (not hay!) It is clean and rarely has weeds or other seeds in it. You get an occasional sprig of barley that is simple to pull and lay with the rest of the mulch. Spread the straw three or four inches thick, thinning carefully at the base of plants. It holds moisture, prevents unwanted seedlings from sprouting and can be turned into the soil or added to compost at the end of the season. Water is crucial. Consistent deep watering, whether you use in-line drip tubing, soaker hoses or attentive hand watering, is important. The soil must not dry out or be too wet. Most containers will need water every day or two. Pay attention, ask your gardening friends questions, share stories of failure and success and enjoy the fruits of your labor!

Author:  Wes Brittenham Farm & Landscape Manager, Los Poblanos Historic Inn & Organic Farm  Have a question about the article? AskAnExpert@abcwua.org

Make this the year that you replace your thirsty lawn with a desert-friendly xeriscape.

Make this the year that you replace your thirsty lawn with a desert-friendly xeriscape.

Current Drought conditions mean even more water will need to be used for your high-water use lawn to remain healthy. If you have been thinking about transforming your lawn into a desert friendly xeriscape there is no better time to do it than right now! These types of landscapes are more resilient to climate variability and can provide for up to 30% in water savings or more. Rebates of $1.00 per square foot are available for our residential customers. Certain restrictions apply, and your plans must be approved in advance by Water Authority staff so don’t start removing your lawn until you have submitted an application and contacted the inspector. Learn about our Xeriscape rebate here and get the link to the application portal.

Our expert staff can provide advice and free resources on how to start your beautiful xeriscape transformation. If your application is approved an inspection will be scheduled to verify that your grass type is considered high water use and has sprinkler irrigation. The grass must be currently cared for at the time of the inspection to qualify for the rebate. The  inspection is a great opportunity to ask questions and get opinions from our xeriscape expert on various aspects of transformation projects such as plant selection, irrigation conversion and tips for saving money by doing it yourself or hiring a professional landscaper.

To remove your lawn we recommend using a sod cutter because it’s a fast and effective, chemical-free method to remove your lawn.  Many local equipment rental companies rent sod cutters. Approved participants of the xeriscape conversion rebate program may receive 25% up to $100 in rebate off the cost of renting equipment like a sodcutter or skidsteer for removing grass. Before removing the lawn, make sure the soil is not too wet or too dry. Set the cutting blade depth at the shallowest setting necessary on the sod cutter to help retain as much valuable soil on site as possible. The removed sod should be recycled at one of our local composting facilities. One advantage of using a sod cutter is that it is chemical-free, fast, and you can continue with the next step of your project on that same day.

Please note: This method is not recommended for lawns that have mature trees. Sod cutters can damage shallow, fine-hair feeder roots that are critical for water and air uptake.  Sod cutters are also not recommended for lawns with Bermuda grass due to the nature of its rooting system. For these cases you might want to consider herbicides. Take advantage of our free ask an expert email service if you have questions about what type of lawn you have or any other questions about xeriscape transformations.

Additionally, xeriscape rebate participants get 25% off the cost of installing bulk organic mulch up to $100. Not only is organic mulch such as shredded wood chips, aesthetically appealing, it provides numerous other benefits. Mulch increases moisture retention in the soil, encourages healthy root establishment, and greatly reduces weeds. A 3”-4” thick layer of organic mulch and drip irrigation are two of the best tools we have for keeping our landscapes healthy and resilient in times of drought.

Check out the Desert Friendly Xeriscape Rebate page to learn more about the qualifications, requirements and process to apply for this generous rebate. You may also contact our xeriscape specialist Amos Arber, at aarber@abcwua.org  or 505-208-2015

Author: Amos Arber, Xeriscape Incentive Inspector, and Certified Arborist for the Water Conservation Department of the Water Authority. Have a question about the article? AskAnExpert@abcwua.org
The Life and Dry Times of 505 Trees

The Life and Dry Times of 505 Trees

As I write this, a cold thin snow cover still hides the ground, but it won’t last long. If we’re lucky, the snow will slowly melt and seep into the soil; if we aren’t lucky, it will sublimate right into the atmosphere – straight from solid to gas. Alas, the roots of our trees lie in the dry desert soil, waiting for water.

It’s always that way, here in the arid Southwest. Our soil, lacking in moisture, also lacks living and dead organic matter. The water that falls on our land either falls infrequently, too little or too much all at once. Still, the plants and trees persist. It is up to us, the human caretakers of these places and trees, to do whatever we reasonably can to provide them with what they need to survive.

Sounds kinda doom-and-gloom, you say? It does! This year promises to be very dry and likely very hot. We all need to do our part to conserve water, and yet we want to keep those established trees healthy and help recently planted trees get established. So, what to do?

It turns out that the two best things we can do are relatively simple. We can reasonably and regularly irrigate the trees (more details below) and apply a layer of coarse organic material as a mulch over the root zone of our trees. 

Since every tree in every yard is different, how often you’ll need to water your trees largely depends on how quickly water moves through the soil. In sandy and gravelly areas (Westside and Foothills), the water passes through the soil quickly, moving past the tree roots. These types of soil need watering more often but with less water each time.

Here is how to do it: Water long enough that after a day, when the water has soaked in, the soil has been moistened about 16-24 inches deep. Poke a thin piece of metal (a long screwdriver or something similar will work) into the ground and see how deep you can push it in. That will tell you approximately how deep the water penetrated the soil.

Do this in a broad area, focusing not on the trunk but on the part of the ground under the outer half of the canopy and maybe a bit beyond the drip line (edge of the canopy).  Feel the soil with your fingers to determine when to water again. You don’t want to let the soil completely dry out between irrigations! Also, pay attention to the leaves, noticing if they are full and flush or droopy and tired.

The best way to water soil that has more clay in it is to irrigate less often but with more water. This kind of soil holds more water, but that water moves slowly. Be careful not to overwater, especially near the trunk. Too much water in the soil interferes with root function and can more easily lead to root rot and decay issues. Concentrate the water in the outer half, and also in a bit of the canopy shadow, all the way around the tree.

Wood chips, which can be obtained from a tree service or a local vendor, are the ideal mulch for trees. No matter what soil type and irrigation pattern you have, putting approximately three inches of wood chip mulch directly on the soil does wonders for your trees. As with any mulch, wood chips cover and cool the soil and reduce evaporation. As the chips decay, they foster the development of a forest-like soil ecosystem, which is just what tree roots really benefit from. Think of the ground surface in a forest — bits and pieces of old trees, slowly decaying at the surface. Add a new layer of mulch every couple of years, and watch your trees thrive! 

Other mulches, like pine bark chips or pecan shells, are not quite as good as wood chips. Rock mulch is not a good choice. It absorbs sunlight and releases that energy as heat that rises through the tree’s canopy and strips even more precious moisture from stressed leaves.

Did you know that the Water Utility Authority will help cover the cost of some of this work? Through the Treebate program, they will offset a portion of the cost of certain purchases — such as new trees — and activities such as pruning and other maintenance work, soil improvements through compost and mulch and even some irrigation costs. Check out tree recommendations and all the program details here.

Author and Photography: Joran Viers, Senior Partner at Root to Shoot Urban Forestry, Inc. find him at joran@root2shooturbanforestry.com  Have a question about the article? AskAnExpert@abcwua.org