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For those who live in the western half of the United States, water has always been a precious resource. In recent years, this has become especially true during a long-term drought has made its impact felt.

As a result, many of us find ourselves looking for ways to save water. The first place you should start is your landscape as that is the largest percentage of your water consumption.

Today, I’d like to show you examples of three different low water landscape options: 

Option #1

Drought Tolerant – This landscape is characterized by lush green, semi-tropical flowering plants. These include bougainvillea, lantana, oleanders, and yellow bells. All these do well in hot, arid climates in zones 9 and above. While most aren’t native to the Southwest, they are considered moderately drought tolerant and suitable for those who want more a lush look for the desert garden.  
For best results, deep water approximately once a week in summer and every 2 weeks in winter.
 

Option #2

Moderately Drought Tolerant – Native, flowering plants make up this type of landscape.  Plants like chuparosa, damianita, penstemon, Texas sage, and turpentine bush are examples of this.
Because these plants are native to the Southwestern region, they need infrequent watering to look their best – a good guideline is to water deeply approximately every 10 days in summer and every 3 weeks in winter.
 
 

Option #3

Extremely Drought Tolerant – For a landscape to exist on very little water, a collection of cacti and succulents are the way to go. Columnar cacti such as Mexican fence post, organ pipe, saguaro, and totem pole add height to the garden. Lower growing succulents like agave, candelilla, and desert milkweed can be used for mid-level interest.  
Golden barrel, hedgehog cacti and mammillaria fill in smaller spaces and look great next to boulders. Once established, they do best with watering approximately every 3 weeks spring through fall.
online-class-desert-gardening-101

Tired of struggling in the desert garden? Sign up for my online course, DESERT GARDENING 101.

 
It’s important to note that shrubs should be watered deeply to a depth of 2 ft., which promotes deep root growth, and the soil stays moister longer. Succulents do well at 12″ depth. 
**Watering guidelines can vary from region to region within the desert Southwest, so it’s wise to consult with your local city’s landscape watering guidelines.
 
Whichever option you select, creating an attractive water-saving landscape is within your reach that will thrive in our drought-stricken region.
The next time you find yourself grumbling about having to prune your trees and shrubs – just be thankful that you don’t have to prune cacti at the Desert Botanical Garden.

While I have never had to prune a large bed of cacti, I have backed into cholla that lined the golf course where I worked.  I had a piece stuck on the back of my leg – Ouch!

Some cacti like prickly pear and cholla sometimes need to be pruned from time to time in a landscape setting.

Prickly pear can grow very large and spread.  If you don’t have enough room, you may find yourself having to prune it back.  When pruning prickly pear, make your pruning cuts where the individual pads, meet.


Cholla tend to drop segments on the ground, which are how they propagate.  The segments will root in ideal conditions and grow a new cholla.

In a managed landscape, it is a good idea to clean the fallen pieces of cholla to help keep people from inadvertently getting it stuck to their shoes.

**Have you ever wondered why cacti have thorns?  I wrote about the surprising reasons that cacti are prickly and some tips for pulling out cactus spines, if you get stuck…


Have you ever gotten pricked by a cactus?  I’d love to hear your story 😉

What comes to mind when you think of cactus?  

Perhaps the first thing you think of is the spines. If you have ever been unfortunate enough to have been pricked by a cactus, you’ll likely never forget that most of them have needles.  
*Did I ever tell you about the time I worked on golf course landscape and backed into a teddy bear cholla and got an entire piece lodged in the back of my leg?
 
Besides being painful to those who get too near to cacti, did you know that there are important reasons that cacti have spines?

Golden barrel cactuses (Echinocactus grusonii)

First, let’s look at the spines of cactus for what they are – the main part of cactus often functions as a modified stem, and its needles are the leaves.
 
The most obvious function of cactus spines is to protect the cacti from animals and people. There are, however, a few animals who aren’t deterred by the sharp spines of cacti such as javelina, tortoises and pack rats.

Saguaro cactus (Carnegiea gigantea) spines

 
Suprise, the primary function of the spines are to actually shade the cactus.
 
Although just one small spine would hardly provide shade, thousands of them can provide enough.
 

Why is sun protection needed for the surface of cacti? The shade from the spines let the cactus lose water through the atmosphere. This helps keep the cactus temperature relatively low.

Black-spine prickly pear (Opuntia macrocentra)

 Another function that the spines serve is that they help certain species of cacti such as cholla to root and spread.

Teddy bear cholla (Opuntia bigelovii)

Spines of the Cholla are specialized to detach and attach onto anything that comes to close. There are tiny barbs at the tips which grab on to anything that gets too close. It almost appears as if they ‘jump’ off of the main cactus as they latch on the unlucky recipient.

Segments of the Cholla are usually moved and then fall off and grow in better conditions. If you have ever seen cholla growing in large groups, this is why. 
**If like me, you are ever unlucky enough to find a piece of cholla embedded in your clothes or worse, your skin – you can use a comb to help pull out the barbs.  When hiking in the desert, it is easy to get them stuck on your shoes.  I usually grab a rock and use it to push off the Cholla segment.  When all else fails, a good pair of needle-nose pliers works.
 

Two young saguaro cactuses are emerging from the shelter of a creosote shrub.

Hopefully, you have a new appreciation for cacti and their spines.  But, it’s still important to be careful because it hurts when you get pricked!
Young saguaro cactus were peeking out from its bursage nurse plant.

As you walk through the desert, there are many opportunities to view some of the striking cacti and their unique shapes.  What is not initially apparent, are the many examples of plants helping young cacti survive.  However, if you look closely, it is all around you – desert shrubs and trees sheltering growing cacti from the harsh desert climate. 

Young barrel cactus underneath a bursage nurse plant
Despite their tough, prickly appearance, cactus are quite vulnerable.  Of the thousands of seeds that are released by each cactus, only a tiny fraction grow into new cactus plants.  Most would not survive if it were not for “nurse plants.”   These plants provide much-needed protection from the sun, cold temperatures and predators (including humans).  Nurse plants also provide much needed additional moisture for the new cacti.

Mammillaria microcarpa 

It is easy to walk by and not even notice the presence of the small cacti growing underneath nurse plants.  Most of the year, the fishhook cactus (Mammillaria microcarpa), pictured above, are almost impossible to see.  It is only in the spring when they are blooming that you can spot them.

Hedgehog cactus outgrowing it’s bursage nurse plant.

For the smaller cacti species, bursage (Ambrosia deltoidea) most often serves as the nurse plant.  It also often serves as the first nurse plant for saguaro cacti.

 
Two young saguaro cacti outgrowing their creosote and bursage nurse plants
 
Creosote (Larrea tridentata), palo verde, mesquite or ironwood trees often serve as the nurse plants for larger species of cacti.  As it grows larger, it requires more water and nutrients from the soil, which leaves little for the nurse plant.  So frequently, the nurse plant will decline and die as you can see from the photo above.

Young buckhorn cholla emerging from its bursage nurse plant.    

So next time you have the opportunity to take a walk in the desert, look around….you will most likely see examples of this unique relationship of plants helping young cactus survive.

Agave macroacantha with ‘Firesticks’
 Succulents are some of my favorite types of plants. I especially like the smaller agave species such as Agave parryi, Agave victoria-reginae, and Agave bovicornuta to name a few.

Let’s talk a little about how to care for cacti and succulents. 

Silver Spurge (Gopher Plant)

Agave, cactus, yuccas, as well as other succulent plants, can continue to be planted during this month. Warm soil temperatures are necessary for succulents to grow and they do best when planted during the warm season.

‘Baby Rita’

Contrary to popular opinion, newly planted succulent plants need to be watered in order to become established and grow a healthy root system.

Established cacti appreciate some supplemental water during the summer months, (especially this summer with our non-existent monsoon). I typically water large cacti with a garden hose about once a month in the summer unless we have had a lot of rain.

Lophocereus schottii ‘Monstrose’

Some cacti and agave plants may show signs of yellowing in the summer. This is usually due to high temperatures. Be sure to give them some supplemental water if you notice the yellowing. Usually, the yellow color disappears once temperatures cool down in the fall.