A few weeks ago, I had the opportunity to take another photo of a landscape I passed by in a neighborhood where I had just finished up a landscape consultation.

Sadly, I often see examples of truly ‘interesting’ or should I say ‘bad’ pruning.  I drove by this landscape and then made a U-turn so that I could take a quick photo…

Shrub pruning

Shrub pruning

I don’t know about you, but these Texas sage shrubs look like mushrooms, don’t you think?

Sadly, pruning these beautiful flowering shrubs this way, robs them of their flowers, increases maintenance, creates dead wood and shortens their life.

While there are quite a few shrubs that take well to repeated formal pruning – doing this to flowering shrubs should be avoided.

I must admit that I have seen Texas sage and other flowering shrubs pruned into many different shapes…

But, let me be frank – shrubs aren’t meant to be cupcakes, frisbees or gumdrops

Here are just a few reasons why…

  • It removes the leaves needed for the shrub to make energy for itself
  • Excessive pruning actually makes your shrubs grow faster, which equals MORE maintenance
  • Shrubs pruned often require more water as they constantly work to replace foliage lost
  • Continued shearing will shorten the lifespan of your shrubs
  • Green ‘blobs’ are ugly compared to beautiful flowering shrubs

If you are tired of the time and money it takes to maintain flowering shrubs the ‘wrong’ way. I invite you to join me in my online shrub pruning workshop where I will teach you the right way to prune.

Imagine your outdoor space filled with beautiful, flowering shrubs instead of green ‘balls’. Believe it or not, the shrubs in the photo above are the SAME plant – they have just been maintained differently. The one on the left takes much more money and time and the other thrives with pruning once (or twice) a year.

In my online class, I show you how to work with your landscaper or how you can take care of your shrubs yourself. Got ‘green balls’ already in your landscape? I’ll teach you how to rejuvenate them and the best time of year to do it.

So, ditch the ‘green blobs’ in your yard and learn how to prune with confidence – it’s much easier than you think. Learn more here and what students have to say about the class.

yellow flowering tree
‘Desert Museum’ Palo Verde

One of the most popular trees for arid climates is the ‘Desert Museum’ Palo Verde. Once you see one, it’s easy to see why it is present in so many residential, commercial, and community areas.

Its medium-green trunk, feathery foliage, and golden flowers, that appear in late spring, add beauty to any landscape. Another characteristic of this palo verde tree is that is has a moderate to fast rate of growth. The branches lets in enough sunlight so many plants can grow underneath its canopy.

BUT, there is another side to these lovely trees that may dissuade people from growing them and that is wind damage.

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

I’ve heard murmurs from people who don’t want to plant these trees any longer because of their susceptibility to damage from high winds.

However, most of these problems are caused by improper maintenance, poor location, and not selecting the right ‘type’ of Desert Museum palo verde.

Desert Museum Palo Verde tree in my backyard

I have three ‘Desert Museum’ 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. Of course, there has been a couple of instances of branch breakage, but the trees recovered nicely. Broken branches is a natural part of life with trees – particularly those native to the desert.

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:

1. Water deeply to a depth of 3 feet. Deep roots are key to the stability of a tree and also decreases the chance of uplifting roots. Apply water toward the outer reaches of the branches where the roots are concentrated. As a tree grows, there 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.

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

2. Irrigate less frequently 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.

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.

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 heavy weight or branches that are weakly attached.

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

Palo verde trees are a great choice for the desert garden that add welcome beauty and shade. If you have a ‘Desert Museum’ palo verde (or other native desert tree), I encourage you to follow these tips to help ensure a beautiful and stable tree for years to come.

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

 

Have you ever had a sunburn?  Maybe a better question is, “Who hasn’t?”  

Well, did you know that many plants get too much as well?

I recently made a house call for a client who was worried about her newly planted citrus trees.

new citrus trees planted in pots.

Sunburned Citrus

This particular client has a large courtyard with several new citrus trees in pots.

The citrus were planted in spring and as summer progressed, the client noticed the leaves on her orange tree turning yellow.

sunburned citrus

Now yellow leaves can indicate a number of different problems.  But in this case, the diagnosis was rather simple – her citrus tree has a case of sunburn.

Here are some common signs of sunburned plants:

– The areas of the leaf that are yellow are in the center and NOT along the tips or edges.

– Often, the yellow areas begin to turn brown.

– Signs normally occur in the summer months.

– The sunburned leaves are usually located on the south and west-facing parts of the plant.

– This particular citrus tree is in an area that receives reflected, afternoon sun.

So, what can you do to prevent sunburned citrus?

In this case, the solution is simple – moving the citrus tree to another part of the courtyard that receives afternoon shade is all that is needed to prevent further sunburn damage. OR, 50% shade cloth can be used from mid-May through September.

Citrus do best when planted at least 10 – 15 ft. away from walls, which absorb the heat of the day and re-radiate it out.

Avoid planting where they get the full force of afternoon sun.

Summers in the desert garden are hot. That’s no surprise. However, there are periods within these hot months that temperatures climb higher than normal. Because of this, we do need to help protect our gardens from the effects of a heatwave.

So, what is considered a heatwave in the low to mid-altitude desert? As a rule, when the mercury edges above 110 degrees F. During a heatwave, they can even go close to 120 degrees – ouch!

Thankfully, there are things you can do to help prepare the plants within your garden right now.

Here is my #1 tip…

Water your plants deeply the night before three – four day span of 110+ degree are forecast. This is in addition to your regular drip irrigation schedule.

The goal of this supplemental irrigation is to water deeply. This allow the soil to stay moister for longer, which will benefit your plants.

Under normal circumstances, I water my plants for 1 1/2 hours. However, in preparation of a heatwave, I water 2-3 hours. Plants will need more water in order to deal with the extreme temps and the extra water that will be lost to the atmosphere through their leaves.

Don’t do this every night, only every 4 days or so during a heatwave.

My second piece of advice…

Provide temporary shade for young plants in your landscape as they are more susceptible to stress from a heatwave.

This is because they don’t have a well-established root system to uptake much water and sparser foliage, so there aren’t many leaves to shade other parts of the plant.

Shade cloth is useful for protection lasting over several months. But for short-term shade during a heatwave, you can use burlap, sheets, an umbrella, or even place a patio chair over a susceptible plant. Uncover plants once temperatures are within the normal range.

Hot temperatures are a fact of life during the desert summer as are heatwaves. But, implementing one, or both, of these tips will help the plants in your garden.

For more tips for heat-proofing your garden, check out Heatproof Garden: 5 Amazing Tips.

Many of us are familiar with how over-pruning can take away much of the beauty of flowering shrubs, in addition to contributing to their early death.

But, have you ever wondered what they look on the inside?

I found this ‘ugly’ example alongside the drive-thru of Taco Bell.

Over Pruned Shrubs

Over Pruned Shrubs

It isn’t pretty, is it?

The side of the ‘Green Cloud’ Texas Sage was sheared away because it was growing over the curb.

The result of planting the shrub too close, OR the wrong plant in the wrong space .

You can see the thin layer of leaves that cover the shrub and the dark, interior where sunlight seldom reaches.

This isn’t healthy for your shrubs, shortens their lifespan, and increases the amount of water they require.

If this resembles your shrub(s), the good news is that you can often fix them.

Over Pruned Shrubs

Imagine going from the shrub on the left to the one on the right?

It is possible and often a certain type of pruning known as ‘rejuvenation pruning’ is the way to do this.

In my online shrub pruning workshop I love teaching my students how to rejuvenate their over-pruned shrubs.

It’s important to not that not all shrubs respond to rejuvenation pruning, but Cassia (Senna species), Sage (Leucophyllum species), Ruellia, Fairy Duster (Calliandra species) and Lantana shrubs respond well as long as they aren’t too old and healthy.

I encourage you to declare your landscape free of shrubs pruned into balls, cupcakes, and squares and transform it into one filled with beauty 🙂

Landscape No-No

Photo: Landscape No-No

Have you ever driven past a landscape that had some problems with it?  As a horticulturist and landscape consultant, my attention diverts whenever I see ‘Landscape No-No’s’ like this one.

Awhile ago, I shared the photo of the landscape, above, on my Facebook page and invited people to identify three things wrong with the landscape.  I received a lot of comments including “looks like Versailles by the inept” and “shrubs arranged like funny looking ottomans spread across gravel.”  

It’s important to not that my reasons for showing examples like this aren’t to shame the homeowners. Instead, my goal is to help others to learn to identify problems and give them easy steps to correct or avoid them in the first place.

So, using this landscape as an example, let’s look at the problems and later, focus on how to solve them:

shrubs pruned the wrong way

1. Shrubs are planted too closely together.  

It’s obvious that there are too many plants in this area and the mature size of the shrubs wasn’t factored in the original design.  The types of flowering shrubs in this area – desert ruellia (Ruellia peninsularis),  Baja fairy duster (Calliandra californica), and ‘Green Cloud’ sage (Leucophyllum frutescens ‘Green Cloud’) are good choices. The problem is that they are spaced too closely together and pruned the wrong way.

2. Lack of different plant types. 

As you can see, there is a tree, a couple of succulents (prickly pear cactus & yucca), and a LOT of shrubs.  However, the landscape suffers from an overabundance of shrubs.  

3. Incorrectly pruned flowering shrubs. 

These lovely, flowering shrubs have been turned into anonymous, green blobs, lacking in beauty and character.  In fact, you would have to look closely to be able to identify what each shrub is.  The problem has to do with what is missing from this landscape, which are attractive shrubs allowed to grow into their natural shapes, covered in colorful flowers.  Other problems associated with maintaining flowering shrubs this way is that it is stressful for the plant, shortens their lifespan, causes to them to use more water to regrow their leaves, and creates more maintenance.

Now that we have identified the problems, we can now look at the solutions.  I will use the landscape above as my example:

landscape-no-no-badly-pruned-shrubs
  • Remove excess shrubs.  Take out 24 of the existing 32 shrubs so that you are left with eight flowering shrubs.  To decide what shrubs to remove, learn what type of shrub they are and look up how large they are at maturity.  Then, make sure that the ones that remain have enough room to grow.  Shrubs should be places up near the house, to anchor the corners of the landscape, and flank an entry.
  • Severely prune back remaining shrubs.  One of the things I love about shrubs is that quite a few have a ‘restart button’ where much of the damage that has been done due to excessive pruning can be reversed.  Severe renewal pruning entails pruning back shrubs to approximately 1 1/2 feet tall and wide in spring. You’ll have nothing left but woody branches and little to no leaves.  However, this stimulates plants to produce new, healthy growth. This type of pruning should be done in spring.  The key is to keep hedge trimmers away from your newly pruned shrubs forever. Any pruning should be done using hand pruners, loppers, and pruning saws.  This will work with most shrubs except for a few that were in declining health.
Which one would you rather have? Learn how to maintain shrubs the right way in the desert garden in my popular shrub pruning workshop

Photo: Which one would you rather have? Learn how to maintain shrubs the right way in the desert garden in my popular shrub pruning workshop

  • Incorporate lower-growing plants such as groundcovers and succulents. A well-designed landscape has plants with varying heights, including those at ground level.  For the landscape above, I’d add a few boulders and plant some gopher plant (Euphorbia rigida) and twin-flower agave (Agave geminiflora) alongside them.  Other ideas for low-growing succulents include ‘Blue Elf’ aloe, Moroccan mound, and artichoke agave.  Flowering groundcovers would also look nice like angelita daisy (Tetraneuris acaulis), blackfoot daisy (Melampodium leucanthum), and sandpaper verbena (Glandularia rigida).  I like to use damianita, trailing lantana, and penstemon for color at lower heights.
Texas sage shrub with natural shape

Photo: Attractive desert landscape with room for plants to grow

Here is a snapshot of a landscape area at the Desert Botanical Garden where plants have room to grow and are allowed to grow into their natural shape and form.

Transforming the problematic landscape shown earlier, and others like it isn’t difficult, and the results are dramatic.  What you are left with is a beautiful landscape filled with healthy plants that use less water and needs little maintenance.

If you are tired of shapeless shrubs shaped like green blobs, I invite you to learn more about how to prune ‘right’ way in my online Shrub Pruning Workshop.

Desert Garden heat with little fuss.

Let’s face it. Hot summers are not surprising to desert dwellers. In fact, a typical desert garden with native and desert-adapted plants will weather intense heat with little fuss.

However, this summer has been one for the books and I’ve seen signs of heat-stress that I’ve never seen before. And yes, within my own garden.

Desert Garden heat-stressed Rock Penstemon and Golden Barrel Cactus

Heat-stressed Rock Penstemon and Golden Barrel Cactus

I must admit that it’s been hard to see certain plants struggling in my desert garden and I know you may have similar feelings. So, why has this summer been so much more difficult than others?

Pink Trumpet Vine partially defoliated due to the heat in desert garden

Pink Trumpet Vine partially defoliated due to the heat

While it is normal to have several days above 110 degrees F., the summer of 2020 is one for the record books. We have experienced not just a couple of stretches of above-normal temps but, several long spans of infernal heat. Damage to plants is often cumulative. This means that the more days of above-average (or below-average) temperatures – the higher incidence of reaction from plants.

Take a walk outside in your garden. You will likely notice some plants that are yellowing, wilting, or have given up and died. However, you may also note that there are some that are doing well.

Why is that? Let me show you some examples from my own garden – the good AND the ugly.

Let’s start with the ugly:

New Mexican Fence Post cactus transplants desert garden

New Mexican Fence Post cactus transplants

In March, much of my backyard was renovated. This included the addition of two separate plantings of Mexican Fence Post cacti. They are located along my back wall and as you can see, one is doing very well while the other makes me cringe when I see the yellowing.

Does the yellowing cactus need more or less water? No. Many succulents yellow in response to summer heat. Of course, this very hot summer has made it more severe. So, why the difference between the two?

The one on the left gets filtered shade in the afternoon from a nearby Palo Verde tree. You can tell that the one on the right doesn’t get any shade but full afternoon sun. In a normal summer, it would be normal to see some yellowing that will return to green once temperatures cool. I am hopeful that will happen. As plants age, they tend to handle heat stress better and as these are young, the stress was especially severe.

Signs of heat stress desert garden

Signs of heat stress

In another area of my garden, I have Green Desert Spoon and Hardy Spineless Prickly Pear, which are very heat-adapted. Yet, they do show signs of mild heat-stress that I haven’t seen before. But, they will green back up in fall. Other plants that are struggling include Artichoke Agave, Gopher Plant, and Shrubby Germander.

I am thrilled that my young Desert Willow tree in this photo is thriving despite the heat. I have four others scattered throughout my landscape and all are doing just as well.

Here are some of the good:

Young Baja Ruellia (Ruellia peninsularis) doing very well in desert garden

Young Baja Ruellia (Ruellia peninsularis) doing very well. The neighbor’s Dwarf Myrtle isn’t.

'Sparky' Tecoma shrub (Tecoma 'Sparky') in desert garden

‘Sparky’ Tecoma shrub (Tecoma ‘Sparky’)

Pink Muhly (Muhlenbergia capillaris). Will soon burst forth in burgundy plumes in fall

Pink Muhly (Muhlenbergia capillaris). Will soon burst forth in burgundy plumes in fall.

Gold Lantana in full sun all day in desert garden

Gold Lantana in full sun all day

Feathery Cassia, Purple Trailing Lantana, and Yellow Bell shrubs are also doing well.

Here are a couple of exceptional performers that get full, reflected sun:

'Rio Bravo' Texas Sage in desert garden

‘Rio Bravo’ Texas Sage

Bougainvillea in desert garden

Bougainvillea

There are still six weeks of summer heat ahead of us. So, what should we do for now?

  1. Be sure plants are receiving enough water. You may need to increase the frequency when temps are above 110 degrees.
  2. Don’t fertilize. Feeding plants simply makes them work harder to produce new growth when all they are trying to do is deal with the heat.
  3. Don’t prune away heat-damaged growth until September. While brown leaves are ugly, they are protecting the interior of the plant. Some pruning is recommended in mid-September, which I teach in my Shrub Pruning Workshop.
garden in the desert with small tree and plants

We don’t know if this summer will be an anomaly or the beginning of a new normal. But, instead of throwing in the towel, I invite you to do the following instead:

Take a stroll through your garden and take note of which plants are doing well and those that aren’t. If this is to be the new norm, it would be a good idea to add more of those that handle the heat well.

desert garden

I am not going to make any major changes in my own garden. Most of my plants have done just fine in past summers. I’ll replace the few plants that died but am hopeful that next summer will be one with average temperatures. If not, then I know what plants have withstood the heat best.

Before we know it, fall will be here, and I for one, can’t wait!

Gorgeous Germander for Desert Gardens

mesquite tree Branches

Have you ever paused in the shade of a mesquite tree (Prosopis spp.) and noticed that its branches grow every which way? 

I was reminded of this when I was visiting a client earlier this week and was advising him on how to care for his mesquite tree. I looked up and saw a cluster of branches growing up, down, sideways, and in curvy pathways.

mesquite tree Branches

Texas Honey Mesquite (Prosopis glandulosa)

In an ideal situation, mesquite trees resemble the shape of more traditional tree species, as shown above. However, they don’t always turn out this way. 

mesquite tree Branches

Have you ever wondered why mesquite trees grow in such crazy ways?

The answer is quite simple – in nature, mesquites grow as large shrubs. The branches of shrubs grow in all directions, up, down, sideways, etc., and so do mesquites.  

The problem arises when we train them up as trees, and their branches don’t always behave as trees do. Because of this, mesquites that have been pruned into trees, do best being pruned by a professional, particularly when they are young and certain branches are being chosen to remain while others are pruned off.

mesquite tree Branches

Of course, this doesn’t always happen, and you can see the results of bad pruning practices in many places. 

I do love the shade that mesquite trees provide and I must admit that I enjoy a good chuckle when I see the unusual shapes that some mesquite trees have taken.

How about you? Have you ever seen a mesquite tree with crazy branches?

To Do About Aphids

What do you do when you spot aphids on your plants?

Do you reach for the nearest bottle of insecticide? Spray them off with a hose or remove them with your fingers?  

Believe it or not, sometimes the best thing is to do nothing.

So, is this something I learned in school? No. I figured it out by observing the plants in my first garden.

To Do About Aphids

I remembered this early lesson when I passed by a severely pruned oleander shrub in front of my favorite bagel shop.  

To Do About Aphids

The oleanders were growing back nicely. However, there were yellow aphids on the young leaves.

Years ago, my oleander shrubs had an infestation of yellow aphids like this, and I was anxious to get rid of them. Really, this is our first reaction when we see bugs on our plants – we want them gone.

I had several methods at my disposal – insecticidal soap, a strong jet of water or my fingers – all of which, would help get rid of most of the aphids. But, life got in the way, and I didn’t have a chance to get out to treat my shrubs until about ten days later.  

Can you guess what I found?  Not a single aphid.  I didn’t have to do a thing, and the aphids were gone, and my shrubs look great.

So, what happened to the aphids?

When harmful insect pests first appear, it can take a week or two before their natural predators follow. In the case of aphids, lacewing and ladybugs showed up and ate the aphids.  

To Do About Aphids

Plants are tougher than we give them credit for and can handle a certain amount of insect pests without any adverse effects.  

So, when I come back in a couple of weeks to the same bagel shop, I expect to see no aphids in sight and a healthy oleander shrub.

The lesson here is that you don’t need to freak out when you see aphids as the normal cycle of nature will take care of them. However, you can step in to get rid of them if you see adverse effects on plants such as wilting, smaller blooms, or discoloration.

No matter where you live, you will see the same shrubs being used over and over again in countless landscapes. While the shrubs may be attractive, their overuse throughout neighborhoods creates a boring appearance because they are so common.

oleanders

In California, Nevada, and Arizona, oleanders have held a prominent spot in the landscape for years. Their popularity is due to their lush evergreen foliage, ability to withstand intense heat, and their pretty flowers.

However, their overuse in many areas makes their beauty less impactful and frankly, almost forgettable.

 At a recent conference, this point was put quite succinctly by the head of horticulture for Disneyland who said,

“When things are expected (in the landscape), they become less powerful and impactful”.

His statement sums up what happens when we use the same plants over and over.

In the case of oleanders, there is another problem.

Oleanders

Oleanders are susceptible to a fatal disease called, oleander leaf scorch. This disease has come from California into Arizona where it is popping up in neighborhoods in Phoenix and also Lake Havasu. I have consulted with several cases affecting large, mature oleanders in Arcadia, Biltmore, and Moon Valley areas in Phoenix. 

This bacterial disease is spread by leaf-hopper insects and there is currently no known cure or control available. Infected oleanders slowly decline over 2-3 years before dying. To date, dwarf oleanders have not shown signs of the disease, only the larger forms. But, that could change sometime in the future.

Objectively, there’s a lot to like about oleanders; they thrive in hot, dry climates with minimal fuss, have attractive dark green foliage, and add color to the landscape when in flower. However, their overuse in the landscape makes them less impactful and coupled with their susceptibility to oleander leaf scorch, people want an alternative. 

You can learn more about this disease that affects oleanders here.

Hop Bush: 

Hop Bush

When asked for another option for the large, tall forms of oleanders, I recommend Hop Bush (Dodonaea viscosa), also known as Hopseed Bush.

Grab my FREE guide for Fuss-Free Plants that thrive in a hot, dry climate!

This native desert shrub has attractive, evergreen foliage and a similar growth habit to oleander. They grow up to 12 feet tall or prune to a shorter height.

Hop Bush

Use Hop Bush in the same ways as oleanders to provide a nice green hedge or privacy screen.

Hop bush flower

Hop bush flower

While they don’t have colorful flowers; they have lovely foliage that is only mildly poisonous as opposed to oleanders which are highly toxic.

Hop bush

Hop bush has a lovely natural shape or prune as a formal hedge.

Want to learn more about this oleander alternative? In my latest Houzz article, I share what types of plants look nice next to hop bush, how to care for them and show a purple-leaf form.

I hope that you find a spot for this lovely shrub in your landscape.

Have you ever seen hop bush growing in the landscape?