Tag Archive for: irrigation

Exploring the Beauty of the Desert Museum Palo Verde

Lovely flowering Desert Museum Palo Verde Tree

‘Desert Museum’ Palo Verde Trees

The Desert Museum Palo Verde (Parkinsonia ‘Desert Museum’), a beloved tree in arid climates, graces numerous residential, commercial, and community landscapes. Its striking medium-green trunk, feathery foliage, and golden late spring flowers contribute to its widespread popularity. While wind damage can be a concern, proper care and selection can ensure these trees thrive.

Avoiding Storm Damage of the Palo Verde Tree

Fallen ‘Desert Museum’ Palo Verde trees after a monsoon storm

These wonderful trees stand as a captivating addition to arid landscapes. Its medium-green trunk, delicate foliage, and vibrant late-spring blooms make it a cherished choice for many. However, understanding and addressing potential wind damage is crucial for their successful growth.

Understanding Wind Damage Concerns

One common hesitation in planting palo verde trees is their perceived susceptibility to wind damage. However, most issues arise from improper maintenance, unsuitable locations, or the selection of the wrong tree type within the Palo Verde family.

Palo Verde Tree in full yellow bloom

Desert Museum Palo Verde tree in my backyard

Personal Success with Desert Museum Palo Verde

I have three of these Palo Verdes around my house. They range in age from 10 to 20 years old. In all that time, I have not lost a single one. While minor branch breakage occurred at times, these resilient trees quickly recovered, showcasing the hardiness of this species.

So, how can you enjoy the beauty of this tree while lessening the danger of wind damage? As a retired certified arborist, I’m here to tell you that there are definitely things you can do.

5 Strategies for Structurally Healthy ‘Desert Museum’ Palo Verdes Trees

1. Water deeply to a depth of 3 feet.

Deep roots are key to the stability of a tree and also decrease the chance of uplifting roots. Apply water toward the outer reaches of the branches where the roots are concentrated. As a tree grows, its roots move outward, so move your drip emitters or hose as needed.

Be sure to plant in an area where there is adequate area for root growth. Parking lot islands and narrow areas don’t allow enough room for roots to anchor the tree.

A blooming Desert Museum Palo Verde Tree

‘Desert Museum’ palo verde that has grown too rapidly due to excess irrigation

2. Irrigate less frequently to avoid your tree growing too fast.

This is a big cause of wind damage with palo verde trees. It’s important to remember that they are desert trees and don’t need as much water as other plants in the landscape. But, people often overwater their desert trees, which causes them to grow too quickly. This causes the formation of weak wood because they haven’t had the time to grow strong trunks and branches. In the photo above, notice how thin the multiple trunks are.

Established native desert trees, that have been in the ground for at least 3 years, can follow these general guidelines – water 1 to 2X a month in spring/fall, 2 to 3X a month in summer, and monthly in winter. These guidelines are for our current drought situation but can be modified as needed.

Several Palo Verde Trees grouped together

Trees that have been pruned up too high (lion-tailing)

3. Prune your tree correctly.

There are examples of awful pruning. One common one is known as ‘lion-tailing’ which is when trees have been over-pruned so the majority of the tree is devoid of branches except for the very top. This pruning deprives the branches of foliage needed to produce energy for the tree and to increase tree strength. It also increases the amount of overhanging branches toward the top making the tree more likely to fall.

Many landscapers don’t know the right way to prune trees and can inadvertently cause harm to your tree. I highly recommend enlisting the services of a certified arborist to prune your tree correctly.

4. Select a multi-trunk form of Palo Verde instead of one growing on a single trunk.

Desert trees naturally in a multiple trunk form, which distributes the weight of the upper branches. Palo Verde trees that have been trained to grow on a single trunk, are under more stress from the wind with their heavy top half. The majority that you see fallen have been trained into a single-trunk tree.

a large desert museum palo verde tree

This tree needs pruning before the monsoon season to lessen the weight of the canopy

5. ‘Desert Museum’ Palo Verde trees generally need pruning at least once (sometimes twice) a year.

You want to be sure to prune them before the onset of monsoon season – removing any heavyweight or branches that are weakly attached.

Desert Museum Palo Verde Tree in the front garden

Newly-pruned ‘Desert Museum’ palo verde tree ready for the monsoon season

Ensuring the Future of Your Desert Museum Palo Verde

Desert Museum Palo Verde trees are a valuable asset to desert gardens, offering beauty and shade. By following these tips, you can safeguard your tree’s health and stability for years to come. Join me in celebrating the enduring allure of these magnificent desert trees.

Want to learn more about this and other Palo Verde tree species? Check out my previous blog post here.

“How much water do my plants need?”

I am often asked this question by desert dwellers and my answer is always, “That depends.”

desert-landscape

There are several variables that determine how much water plants need, along with the frequency of watering.

Variables include:

  • Type of soil (clay, sand, combination)
  • What kind of plant (native plants, higher water use flowering shrubs and ground covers, succulents, etc.)
  • Recommended depth of water
  • Desert region (low-desert, mid-altitude, high desert)
  • Efficiency of irrigation system
  • Water pressure (can vary between neighborhoods)

As you can see, there is no universal watering guideline in regards to how long to water or how often.

Let’s look into the variables a little more closely to help you determine what yours are:

Soil – Clay soils hold onto water longer than sandy soil. They take longer for water to permeate to the recommended depth. The result? Clay soils need irrigation less often than sandy ones but need to be watered for a longer length of time. Phoenix area soil tends to have more clay in them while those in the Palm Springs area are sandy.

Plants – Native or desert-adapted plants need less frequent irrigation versus those that come from tropical climates. Cacti and other succulents do well with infrequent irrigation.

Water Depth – Trees need to be watered deeply while ground covers and succulents do fine at a more shallow depth – shrubs fall in between the two.

Desert Region – Where you live in the desert matters when it comes to water and your plants. The differences include rainfall amounts, when the rain falls, high and low temps, and more. Residents of low-desert cities like Palm Springs and Phoenix need to add water to their plants more often than those who live in higher elevation regions such as Tucson.

Irrigation System – The older your irrigation system, the less efficient it is. This is due to mineral build-up within the system, which affects the amount of water that comes out. Also, old drip irrigation systems tend to accumulate leaks. The average lifespan for a drip irrigation system is 10-15 years. 

Despite these differences, what is a shared characteristic is that the vast majority of desert residents water too often and not deeply enough. This is usually due to lack of knowledge and thinking the ‘more is better,’ especially in the desert.

Landscapers are generally not a reliable source when it comes to scheduling irrigation – most recommend irrigating far too often.

So what is a desert dweller to do?

Thankfully, there is very useful information available for homeowners to help them figure out when and how much water their landscape needs.

Major metropolitan areas throughout the Southwest have excellent watering guidelines available for residents. The guidelines include the regional variables we have discussed so far.

Here are helpful links based on major desert cities (click the link for the city closest to you):

Las Vegas

Palm Springs

Phoenix

Tucson

Watering guidelines are just that – guidelines. Circumstances may mean that you need to water more or less often, but these guides are a useful baseline to work from.

*One final note – before you implement a new irrigation schedule, it’s important to gradually wean your plants to the new one over several weeks. The reason for this is that it allows plants to become accustomed to the new schedule.

Yes, it does take a little work to figure out how much and often to water your plants, but these guides are incredibly helpful and will guide you along the way.

summer rains

Rain shaft heading straight for us.  Torrential rain began to fall just a 1/2 hour after I took this picture.

You would think that living in the desert – that we don’t get much rain.

While it’s true that we don’t get as much rain as most people, we do experience periods of torrential, summer rains.

That has certainly been true, this summer.

Actually, this week, we have had rain every day – often very heavy.

I had a landscape consultation yesterday and the back yard was not landscaped – there was just plain dirt, which had turned to mud.

My shoes are still muddy and drying out in the garage 😉

Approaching thunderstorms as seen from Double S Farms.

My garden has enjoyed the rainfall.  I have shut off my sprinklers and drip irrigation because there is a danger of over-watering plants.

My husband is very happy with how nice our back lawn looks.  The rain and high humidity have really brought out its best.  (The entire garden is my domain, except for our lawn – that is my husband’s).

Unfortunately, we aren’t the only ones who have enjoyed our wet, humid summer – so have the mosquitos.  We have gone through 1/2 a bottle of repellent in just 5 days 😉

And so, as the rain threatens to fall again tonight, I will cheerfully sweep the entry and patio for the fourth time this week because I know all too soon the rain will taper off and become an infrequent visitor.

Okay, I must begin this by admitting that I have no idea what to post about today….

Maybe I shouldn’t admit this to you, but there are times when I have nothing.  I think it may be because there is so much going on in my life. 

hot Southwest summer

– My three youngest kids start school on Monday (we have a modified year-round school calendar).  My daughter Ruthie, begins Jr. High and is understandably nervous.  We went shopping yesterday for some new clothes and shoes.

– We have guests arriving tomorrow from Kansas City who we will be entertaining for the weekend.  There is a very special story behind these people and my daughter Ruthie.  I can’t wait to share it with you later 🙂

– I just finished writing 4 gardening articles and have one more left to go.

– We are busy helping my in-laws each week with miscellaneous tasks around their home.  My father-in-law is continuing to suffer more debilitating effects from ALS.

However, with all of this going on, my garden is thriving.  I thought that I would share with you some summer things that you should do in your garden.  

It is from an article that I wrote earlier this month for a local community newsletter.  I hope you enjoy it 🙂

hot Southwest summer

Thankfully, there is not a lot of things to be done in the garden during the hot Southwest summer, but there are some tasks that are important this time of year.  

I recommend going out into your garden during the early morning hours to do these tasks, as I do, or at dusk, once the sun begins to set to avoid the extremely hot period of the day. So, put on your hat, sunscreen, gloves and sunglasses and let’s get started.

hot Southwest summer

Hot Southwest summer

Succulents: Cacti, agave, yucca and other succulent plants can suffer from both the extreme heat and sun of summer, especially on the side of the plant that points toward the southwest. Signs of heat damage include a yellowing of your succulents. If your succulents are not connected to your irrigation, they need to be watered to a depth of one to two feet. Larger succulents such as saguaro, ocotillo and yuccas need to be watered to three feet deep. Do this once this month and again in August. 

This can be easily done by simply placing your hose next to the plant and barely turning the water on so that the water trickles out slowly. Leave the water on for at least an hour and then check to see if you need to leave the water on for longer.

Shrubs: Make sure that your shrubs are receiving enough water. They should be watered to a depth of 2 feet each time you water. Avoid fertilizing this time of year since this creates more stress for your plants, which are struggling to handle the heat of summer. You can deadhead spent flowers from your shrubs to promote additional bloom, but avoid pruning away any foliage at this time of year. Spider mites can become a problem this time of year. Look for any tiny webs, which are a sign of these tiny mites. Controlling them is easy since they like to hide in the dust, so spray your plants every few days with water to help keep the mites from becoming established.

hot Southwest summer

Hot Southwest summer

Trees: Avoid planting any trees this month, except for palms. Mature, established trees require deep watering this time of year, especially if they are not connected to your irrigation system. This should be done once a month in summer, watering to a depth of 3 feet. Using a hose, allow water to slowly trickle out around the drip line of the tree (where the branches end, not against the trunk) which is where the roots are located. You may need to move the hose so that you water around the entire tree. You can skip one watering if you receive 1 inch of rainfall, which replaces a single irrigation. 

As the increased humidity, (25 – 33% humidity is considered high in the desert), makes it more uncomfortable for us to go outside, it helps to keep in mind that plants just love the extra moisture even if it is only in the air around them.

**I hope you find this helpful.  I wanted to also tell you about a fabulous sight that I saw on our vacation.  I blogged about it on my Birds & Blooms blog.  

Baja fairy duster shrubs up close

Baja Fairy Duster is Hummingbird Food in the Native Garden

Baja fairy duster (Calliandra californica) is a must-have for the desert garden.  There is so much to love about this shrub.  

My favorite attribute is that it flowers off and on all year.  Its red flowers are shaped like miniature feather dusters.  Also, this plant attracts hummingbirds, is low-maintenance, drought tolerant and great by swimming pools because of its low litter.

Baja fairy duster has a vibrant red flower, which is often a color missing in the desert plant palette.  The majority of flowering occurs spring through fall, but some flowering can occur in areas that experience mild winters.  

It is native to Baja California, Mexico and is also called red fairy duster by some.  It is evergreen to 20 degrees F.  During some unusually cold winters when temperatures dropped into the high teens, I have had some killed to the ground, but they quickly grew back from their roots. 

Baja fairy duster flowers

Landscape Uses for the Red Blooming Shrub

This shrub grows to approximately 4 – 5 ft. High and wide, depending on how much you prune it, so allow plenty of room for it to develop.  

It makes a lovely screening shrub, either in front of a wall or blocking pool equipment, etc.  It also serves as a colorful background shrub for smaller perennials such as damianita, blackfoot daisy, Parry’s penstemon, gold or purple lantana and desert marigold.  

Baja fairy duster can take full sun and reflected heat but can also grow in light shade.  It is not particular about soil as long as it is well-drained.

Baja fairy duster shrub with green leaves

  Baja fairy duster in the middle of a desert landscape, flanked by desert spoon to the left and ‘Torch Glow’ bougainvillea to the right.  Red yucca is in the foreground.

Baja Fairy Duster Maintenance

As I mentioned before, this is a very low-maintenance shrub.  Some people shear this shrub, which I DO NOT recommend.  This removes most of the flowers and takes away from the natural shape of this shrub.  However, it’s size can be controlled with proper pruning.  Pruning should be done in late spring and should be performed with hand-pruners, NOT hedge clippers.

Baja fairy duster does require regular irrigation until established but then is relatively drought-tolerant.  However, proper watering is needed for it to look its best and flower regularly, which is what I do.  

Other than adding compost to the planting hole, no other amendments or fertilizer is needed.  Most native desert plants have been adapted to growing in our nutrient deficient soils and do best when left alone in terms of fertilizing.  I tell my clients to fertilize only if the plant shows symptoms of a nutrient deficiency.

So, go to your local plant nursery and get some of these beautiful shrubs for your garden.  Then, while you sit and enjoy its beauty, you can debate what you love most about it….the beautiful year-round flowers, the hummingbirds it attracts, it’s low-maintenance, or come up with your reasons.

santa rita purple prickly cactus

Exploring the Beauty of Prickly Cactus

Do you like prickly cactus? I have a few favorites, one being the Santa-Rita Prickly Pear (Opuntia violaceae var. santa rita). The color contrast of their blue-grey pads and the shades of purple are so striking in the landscape.

The Santa-Rita Prickly Pear: A Stunning Accent Plant

The Santa-Rita prickly pear is a captivating addition to any landscape. Its blue-grey pads and vibrant shades of purple create a visually striking contrast. Not only is this cactus aesthetically pleasing, but both its pads and fruit are edible (though you may want to remove the spines first). Cold temperatures and drought conditions intensify the vivid purple color of this remarkable cactus.

Native Plant Beauty of the Southwest

Native to the Southwestern regions of North America, the Santa-Rita prickly pear can reach impressive dimensions, growing as large as 6 feet by 6 feet. However, if you prefer a smaller size, careful pruning at the junction where the pads connect can maintain a more manageable shape.

prickly cactus in full bloom

Blossoms and Wildlife with Prickly Cactus

In spring, the Santa-Rita prickly pear graces the landscape with lovely yellow flowers that later give way to red fruit during the summer months. Keep in mind that javelina, rabbits, and pack rats are occasional visitors that might nibble on the pads, while pack rats ingeniously use the pads to build their homes.

Handle with Care: Dealing with Spines and Glochids

Prickly pear pads are covered with clusters of 2″ spines and tiny spines known as glochids. Glochids are especially irritating to the skin and easily detach from the pad, making them challenging to remove. When handling these prickly cacti, use multiple layers of newspaper or a piece of carpet to protect your hands. Avoid gloves, as glochids can render them useless.

Removing Glochids Caused by Prickly Cactus

If you encounter glochids with prickly cactus, there are different methods to remove them, including applying Elmer’s glue, allowing it to dry, and then peeling off the glochids. However, many find greater success using duct tape for a more efficient removal process.

close up of prickly cactus

Versatile Uses in Landscaping

Beyond being a landscape accent, the Santa-Rita prickly pear serves as an excellent screen. Surprisingly, it can thrive in containers as well, although it’s essential to keep them away from high-traffic areas. These resilient cacti flourish in full sun or light shade and well-drained soil.

Low-Maintenance Prickly Cactus Beauty

Santa-Rita prickly pears are incredibly low-maintenance plants. When pruning, use tongs or newspaper to handle the trimmed pads. While they are highly drought-tolerant, occasional watering during the hot summer months, especially in the absence of rain, can enhance their appearance. Shriveled pads signal acute drought stress, so a little extra water can work wonders.

santa rita prickly cactus disease

Addressing the Cottony Mystery on Prickly Cactus

Some might mistake white, cotton-like areas on the pads as a fungal infection, but it’s actually caused by a small insect known as cochineal scale. Removing this cottony mass is simple—just spray it off with a strong jet of water from the hose.

pad cactus purchased at garden center

Propagation: A Simple Guide

You can propagate Santa-Rita prickly pear cacti with ease. Simply cut off a pad that is at least 6 inches tall, let it callus upright in a shady, dry spot for about two weeks, and then plant it with the cut end down.

Plant with the cut end down, do not water for the first month because the bottom is susceptible to fungal infections. After the first month, water every 2 – 3 weeks until established. 

Timing Matters

Planting in the summer requires shade until the cactus is established (approximately three months). However, it’s often advisable to wait until spring when the soil warms up for planting, especially in regions with cold winters.

Renewed Growth: Pruning and Propagation

For those with established Santa-Rita prickly pear cacti, you can rejuvenate growth by pruning or starting anew. Simply remove the cactus, cut off some pads, and replant them in the same location. Many have embraced this method and have been delighted with the results.

An Interesting Historical Fact

The Aztecs would cultivate prickly pear cactus infected with cochineal scale because the insects secrete a dark red dye with crushed. This was used to dye cloth. The Spanish exported this dye from Mexico back to Europe where it was used to dye royal garments and British military uniforms. The dye was highly valued by the Spanish, next to gold and silver. It takes 70,000 insects to produce 1 pound of dye.

*This is but one of many beautiful prickly pear species available to the home gardener. Do you have a favorite species of prickly pear cactus?