Category: desert gardens

3 trees for Fall color in desert, but beware

With the limited color range in gardens in hot, dry desert climates–usually shades of brown and muted greens–having a tree outside your window that blazes with reds, yellows and oranges in Fall is a happy choice.

(I have a warning for you about leaves turning yellow at other times of year…but more about that later.)

First, let’s look at 2 big, beautiful, drought-tolerant trees and a small one that signal the change of seasons with their leaves.

These drought-tolerant Chinese Pistache (Pistacia chinensis) trees are still young. When mature, they are excellent shade trees at 40 feet tall and about 30 feet wide. Every Fall their leaves on the male trees turn from summer green to yellow to gold to blazing red–often with all those colors on the tree at one time as you can see in the photo at the top of this post. The female trees simply turn golden yellow. Strictly ornamental trees, they produce small non-edible red berries.

  • Rio Grande Variety of Fan Tex ash tree

The ‘Rio Grande’ cultivar of Fan-Tex ash (Fraxinus velutina) in this photo is about 14 years old. Not only is it a fast grower, it can be ideal for summer shade and winter warmth, after the leaves fall and the sun shines in. Once established, it is drought tolerant. While there are other ash trees that grow well in hot arid gardens — for example, the very fast growing ‘Modesto’ ash–only the ‘Rio Grande’ Fan-Tex ash leaves turn gorgeous gold in Fall. Click on photo to see it in summer.

And a colorful Fall and Spring tree for smaller gardens

If you do not have space for a very large tree, consider planting a crabapple (Malus) tree in your garden. They grow to about 15 feet wide and 15 feet tall. While needing regular watering, the crabapple flowers beautifully in Spring and the leaves turn a lovely orange/red in Fall. See second photo for spring blooms. If you should decide to buy one be sure to ask what the Springtime blooms look like. Some bloom white, some pink, some almost red and some are single blooms, others doubles. And the fruit is edible as a jam or pickle when cooked properly.

Javelina Cousin book ad

Beware of some yellow leaves

You may notice that the leaves on one of your shrubs are turning yellow — but the veins stay green–and it isn’t even Fall. This is an indication of plant chlorosis due to problems with soil conditions, specifically iron deficiency. There are commercial treatments you can use, like Kerex or other iron chelates and other spray-on treatments. They work short term. But improving the overall condition and chemical balance in the soil should be your next step after spraying for longer term results.

Where to get a free or cheap tree for your home.

Listen to Mother Nature

Mother Nature plants in Fall and so should you. By planting at this time of year when the soil temperature has cooled off, the shrubs and trees have the opportunity to develop deep roots over winter and are, thus, stronger plants when they start to grow above-ground next Spring.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

A one color garden–no, make that two

Gardening writer Vita Sackville-West’s ‘White Garden’ at Sissinghurst Castle in the U.K. was revolutionary in 1950. And inspiring to this day.

Instead of a garden filled with billowing rows of mixed-color flowering plants–a style that had dominated English gardens for generations–Sackville-West installed only plants that bloomed in one color: white. According to her weekly gardening column she decided that the plants themselves must have either green or gray leaves. No yellowish or reddish leaves for this garden.

In fact, despite what she said, it was mostly a green garden because the white flowers bloomed only once a year for a brief time. The green color leaves endured year round.

While a garden as lush as seen, above, in this recent photo of Sissinghurst, would be challenging and an utterly wasteful use of water in a hot dry climate, the idea of a one or two color garden continues to appeal to garden designers.

One color and water wise in Las Vegas

Back in the early 2000s a one flower color, water-wise garden took root in Las Vegas. Garden designer Victoria Morgan told me that her primary goal was to create a water-wise green garden. Even back then, the water level in the Colorado River which supplies Las Vegas was falling so drought tolerance was a must, she said.

The flower color that she chose was yellow–and not much of that: just a few Lantana montevidensis by the fountain and nearby. Some additional color came from non-plant sources: painted furniture under the arbor, tiles around the fountain and large blue pots in front of the home, as you can see in this slide show.

grape vines with colorful patio chair and table

Another requirement she set was low maintenance, so there were no flowers to dead-head or fertilize. Shrubs like the Korean boxwood were trimmed once or twice a year. And the tall, shady nut trees that took up a large part of the garden needed attention primarily during harvest. For more photos of this very soothing orchard garden, go here.

Morgan’s use of green with yellow was a natural choice for a Southwestern U.S. hot, dry garden: many native plants (or non-natives like Lantana which thrives in our climate) bloom yellow. Some cacti, of course, produce pink flowers, but yellow is the dominant flower color in the desert, especially when rain comes and sweeping fields of yellow wildflowers spring up among the cacti.

Where to get a free or cheap tree for your home.

Yellow blooming plants and shrubs

Should you decide to plant a green-plus-yellow garden here are a few plants–some native, some not–you could include. In order they are:
Brittlebush (Encelia farinosa)
Mexican Gold Poppy (Escholtzia mexicana)
Desert Marigold (Baileya multiradiata)
Lantana (Lantana montevidensis)
And for larger shrubs:
Mexican bird of Paradise (Caesalpinia mexicana) and
Thevetia (Thevetia peruviana), sometimes called Yellow Oleander, it is pretty but poisonous. (I have one in my backyard; someone else planted it.)

A good tree to include in a green/yellow garden is the wildly popular native Palo Verde (Cercidium parkinsonia). Planted in home gardens, parking lots and growing naturally along dry washes, it is the Arizona State Tree. Blooming brilliant yellow in Spring, it doesn’t offer much shade, however, because its leaves are tiny.

And for yellow color in the Fall–plus shade in summer–a good choice can be the Fan-Tex Rio Grande Ash, below.

Of course, you could choose another color for your one color garden–reds, pinks, purples and magentas–but yellow seems to be a natural garden design choice for the hot dry gardens of the Southwest. Most native plants bloom in yellow.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

So your garden died. What’s next?

While there are two ways to combat plant death-by-dehydration, it is probably too late for many in the U.S. Southwest, especially Arizona and Nevada, after a weeklong stint of record setting heat. (For those of you outside of the SW, there were high temperatures of 110-120F (43-48 celsius) for 8 days in a row and it continues.)

If you still have hopes for some plants in your garden you can do this:
1. Deep water plants more frequently than usual.
2. Hang shade cloth over your plants.

Realistically, however, dead plants — especially vegetables that were planted not long ago–are the new normal in Southwest gardens.

So what comes next?

For starters you can add those dead plants to your compost pile, so all is not wasted! And do not regularly fertilize any plants during summer months in desert climates. Even sturdy native plants are simply hunkering down and trying to survive until cooler weather arrives. Give them water, and in late summer, a tiny taste of fertilizer–that’s all.

Replanting right away is, obviously, not a good idea. Many gardeners now seem to be considering planting only natives when they replace what they lost this summer, but wisely they are waiting until Fall.

I’m thinking about pots on my patio overflowing with non-native Lantana (L. montevidensis) which seems to be able to survive almost anything and continue to flower.

Adios tomatoes and peppers

My vegetable growing experiment of this year will not be repeated. It has become a once-in-a-lifetime experience. I can buy organic veggies and support organic farmers while I eat healthy.

While I have stopped wasting water trying to help my sunflowers, tomatoes and peppers survive, I am still trying to help birds and other wildlife stay alive. I’d suggest that you do this, too.

Set out a shallow plant saucer filled with water and refill at least once a day. It can be a lifesaver for birds, insects and other creatures suffering from the intense heat and scarcity of water.

I’m not sure which creatures drink from this water source on my patio, but at least this Mourning dove has. You could also set up a trail camera to learn which wildlife comes to visit your garden.

Turning your garden into a kind of wildlife preserve may be the best use of that space as climate change brings hotter and dryer conditions. This extreme heat may not be the last.

Where to get a free or cheap tree for your home.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

There outta be a social media law against lawns

*shriek!* Some postings on social media gardening sites drive me crazy!

I just read a post on a Facebook gardening group from a newbie who has planted a big green lawn next to his new home in Arizona. It was, he said, like the one he had Back East. He proudly included photos and thanked other members of the group for all the advice they gave to him. He “couldn’t have done it without them”.

What??!!?

I wonder who told him that a grassy green British lawn was a good idea in a hot, dry climate? That it was a good idea in a land where water has to be imported hundreds of miles across a desert so he can turn a faucet and spill that water on to desert soil where it soaks in an inch or two and/or evaporates almost instantly.

Blame those green lawns on the Brits

Yes. Neatly trimmed green lawns originated in the rainy, damp British Isles. They are not common around private homes in Spain or Italy or Germany or elsewhere in the E.U. or most of the world. And even in the U.K. lawns are a relatively recent innovation that had something to do with wealthy landowners raising sheep or impressing the neighbors or something. Sadly, the lawn idea took hold and jumped across the Atlantic where it spread across the continent–even into Southwest desert communities.

American home builders also are to blame for the U.S. lawn obsession because they planted lawns in massive housing developments particularly after WWII because turf grass in the front yard is easy, cheap and fast landscaping.

Serious drought…really serious

I wonder if that newbie lawn guy, and other well-meaning, but poorly informed, participants in that group, realize how serious the drought conditions are in the U.S. Southwest as the U.S. Drought Monitor shows.

And how fast water tables in towns across the Southwest are falling as local water districts–the ones not relying on Colorado River water–pump more and more local ground water to new housing developments where new homeowners are planting wasteful lawns.

And I wonder if they realize that ground water isn’t being replaced in reservoirs and rivers with rain falling from the sky. The soil just gets drier and drier. The local wells have to go deeper and deeper. And choosing to plant a lawn becomes more and more absurd.

One woman in Pasadena CA pulled out her front lawn and turned it into an astonishing and somewhat bizarre front garden complete with blue bottles and plastic ornaments. This is the strangest lawn replacement I’ve seen. But to each, her/his own!

Local government officials are trying to handle current and future water usage. Efforts to slow down and re-allocate usage of water imported from the Colorado River show up in things like golf courses closing or being converted to dry landscaping and towns passing laws to ban lawns in front yards.

But there are other choices.

Before I show you some attractive lawn-free gardens for hot dry climates I’d like to suggest that if your heart is really set on the look of a lawn consider planting Buffalo Grass (Buchloe dactyloides) an Arizona native grass that many are planting as turf. Originally known as the grass that American buffaloes (bisons) grazed on, it grows green in summer, dies back to brown in the Fall and needs no irrigation and almost no mowing after it is established. [Note: This is not the invasive Buffelgrass (Pennisetum ciliare), an African native that is overwhelming plants in the Sonoran Desert. ]

Beautiful replacements for grassy lawns

So here are a few examples of front yards that are lawn-free.

A front yard filled with blooming perennials including kangaroo paw, sea lavender, rosemary and flat grey dymondia groundcover. This garden is located in Pasadena which gets about 17 inches of rain each year.

A desert-style garden in Springtime when the aloes and other plants are in bloom. This garden is located in Tucson which receives about 12 inches of rainfall a year.

These homeowners added berms, small “hills”, to their previously flat front lawn and planted drought-tolerant shrubs and trees that need almost no maintenance. Goodbye lawnmower! Berms need to be carefully designed to channel rainfall away from the house foundation.

This landscaped garden includes a dry creek bed as an ornamental feature surrounded by agaves and blue-gray fescue grass and taller green deer grass. As with adding berms in a garden, adding a dry creek bed has potential problems. Dry creek beds are not always dry and should be designed so rain water flows away from a home’s foundation.

I think of this front yard with its large decomposed granite space as a Mexican Garden because it reminds me of plazas and courtyards I’ve seen in Mexico. The “bare ground” decomposed granite suppresses weeds and is surrounded by drought tolerant plants that bloom seasonally. Zero maintenance and it requires only the water from the sky.

I was also going to write about silly social media posts praising decorative backyard ponds, but I have ranted enough for today. Those weird backyard ponds are as wasteful as grassy green front lawns in hot dry climates. If you have one, convert it to a flower fountain with plants on each level.

A postscript: there are now over 6,000 Little Free Plant Stands in Arizona! Vastly more than when I wrote about them back in March.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

Happy Solstice – winter and summer!

My wish on today’s Solstice is that this year will be a better year for everyone! 2020 can’t end soon enough!

The light at the end of the proverbial tunnel is brighter now that the roll-out of COVID 19 vaccines has begun.

Now, you can make the natural world better this coming year by planting a tree that’s suitable for your climate to cast shade on your garden and home. The world continues to grow warmer and a tree will help cool it down a bit over the coming decades.

And, if you still have a grassy lawn, make this the year you remove it and plant water-wise shrubs instead. Lawns are fine in wet climates, but an unwise use of water in hot dry gardens.

And, keep in mind that by planting long-living shrubs and trees you are also providing homes for Mother Nature’s other creatures, especially birds and insects.

May your garden thrive this year!

Carol Lightwood
Hot Gardens

The photo at the top of this page was taken at the Tucson Botanical Garden in December 2020.

4 desert trees good for the soil and 4 toxic ones

Recently Tucson’s Mayor Romero announced a tree planting goal for the City: one million new trees planted in the next ten years to help combat climate change. (That works out to 274 trees a day!) Homeowners are encouraged to plant one or more trees around their homes. But the number of tree choices for hot dry gardens runs into the dozens. So how to choose?

Trees related to peas?

In the hot dry gardens of the Mojave and Sonoran deserts homeowners should consider the benefits of planting these 4 trees that belong to the pea family. Why pea family trees? Because they take in abundant nitrogen (NH2) from the air and convert it to ammonium nitrogen (NH4) which gets added to the soil via bacteria-filled nodules on the tree roots.

So, not only do these trees do what all good trees do–provide shade and remove carbon dioxide from the air–they also help other plants beneath and nearby to thrive by providing nitrogen to the soil for nutrition.

You see this everywhere in untouched, natural areas, like this photo from the Saguaro National park: cacti and other plants growing right under and up through trees.

Food for the soil and plants nearby

First on the Good-for-the-Soil List: Mesquite (Prosopis). Among the most common varieties of Mesquite are Argentine mesquite (P. alba), Chilean mesquite (P. chilensis), honey mesquite (P. glandulosa), the screwbean mesquite (P. pubescens ) and velvet mesquite (P. velutina). The honey and velvet mesquites produce edible seeds pods that are commonly ground up into a flour for cooking. The screwbean is quite a messy tree. In size, mesquites range from 8 to 10 foot tall shrubs to 40 foot tall trees.

Mesquite tree prosopis
Mesquite alba in Las Vegas

They are super-easy to grow. On my short walk this morning I noticed dozens of young volunteer mesquite trees sprouting along neglected areas next to the street. If they are left alone, within a few years they will become trees with no help from anyone.

Trivia: in Australia and Ethiopia mesquites were introduced a few decades ago and loved the weather and land so much that they are now regarded as invasive pest trees because they are aggressively taking over grazing lands.

palo verde tree at Sunnyland garden
“Palo Verde Tree, Sunnylands, CA 2-22-14” by inkknife_2000 (11.5 million views) is licensed under CC BY-SA 2.0

Second on the Good-for-the-Soil list: Palo Verde trees (Parkinsonia florida), the Official Arizona State Tree. In Spanish the name means “green stick” with good reason. It is immediately recognizable by the green color of its trunk and nearly leafless branches. In Spring it bursts into bloom with brilliant yellow flowers and small leaves emerge, only to fade away quickly. While it does not cast much shade, it too helps other plants thrive by fixing nitrogen in the earth. The Foothill Palo Verde, which has a more yellow tinge to the trunk, reaches 20 feet in height. The blue Palo Verde can grow to 40 feet tall.

Acacia in bloom at Los Angeles Arboretum

Third, we have the Acacia tree (Acacia), which some claim should be knick-named the “Allergy Tree”. These fast growing Southwest natives love the heat and bloom with yellow powder-puff flowers in the spring that leave a pretty carpet of yellow pollen and spent blooms beneath them. Some also bloom again in the Fall. The larger varieties will reach 40 feet in heights and provide excellent shade, but there is one smaller variety suitable for courtyards.

Food for the soil and people, too

“Carob tree” by tree-species is licensed under CC BY 2.0

Fourth, and a little harder to find, is the Carob tree (Ceratonia siliqua). Not only does this Mediterranean native tree add nitrogen in the soil, it has pods that, when ripe, can be ground up and used as a substitute for chocolate. Be sure to read instructions online if you plan to do this.

Growing to a height of 50 feet carob trees cast dark, cooling shade. Unlike the previous three on this list, it needs some water year ’round. It is, however, on the suggested tree list in Tucson. For whatever it is worth, it is one of my favorite trees and Carob ice cream was very popular among the hipsters in San Francisco in the 1960s.

Javelina Cousin book ad

4 Toxic beauties

But not all trees in the pea family are good. There are some toxic trees in the pea family which are quite beautiful and are planted in hot dry gardens throughout the Southwest–and probably shouldn’t be. While they can fix nitrogen in the soil they are best NOT planted in a family garden because of the dangers they can pose.

The Golden Medallion tree
Golden Medallion tree in Tucson

The striking Golden Chain tree (Laburnum × watereri) is uncommon, temperamental, and all parts are poisonous. The brilliant yellow flowers hang down like long chains of gold, which is where the name comes from.

The Golden Medallion tree (Cassia leptophylla) is similar in appearance to the Golden Chain tree. Its pods are poisonous.

The umbrella-shaped Mimosa tree (Albizia julibrissin) with its pretty pink-white flowers has poisonous seed pods and a reputation for being invasive.

The small Texas Mountain Laurel (Dermatophyllum secundiflorum) is a shrub-like tree with lovely purple blooms that look like wisteria or lilacs. Its brilliant red seed pods are deadly poisonous.

For more information about trees suitable for hot dry gardens, go to our Leafy Trees for Shade page.

Visit my author’s site to see books I’ve written
and read a chapter of the children’s book free

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

Frugal DIY gardening tips for Fall planting

For thousands of years frugal gardening was the only way to garden. Instead of buying starter plants at a local nursery or garden center, people planted seeds they had collected and saved during the previous harvest. Or swapped seeds and cuttings with friends and family. Or divided their own existing plants.

They didn’t buy mulch or composting equipment from those Big Box garden stores either. For century after century they created soil amendments themselves or did without. All gardening was do-it-yourself gardening.

This thrifty approach still works in the 21st century and may be more important than ever, especially for those of us whose gardens scorched right down to the bare earth during the relentless heat this summer. Replacing the plants that died as well as introducing new ones may be what you are facing this Fall. And the expense can be shocking. You may even have moments when you think: Buy groceries? Or buy for the garden?

So here is what to do to create a money-wise, water-wise garden this year.

Your Library is Your Frugal Gardening Friend

Hundreds of public libraries from coast to coast have turned their old card catalogs into bins containing packets of free herb and vegetable seeds. The seeds are most commonly collected locally and packaged in carefully labeled plastic bags by volunteer gardeners. Because the seeds come from their own gardens you know that they should thrive in your climate.

seeds in library card catalog

If your local library does not offer this service, ask them to start one of these “seed banks”. Master Gardeners or members of gardening clubs may be willing to help launch this free seed service.

There are also free seed swap services online. I haven’t used any of them, so I won’t make a specific website recommendation. If you use one, keep in mind that seeds that thrive in one location may not in another, for example, in a hot dry garden. It’s best to find local seed sources.

And DO NOT plant any seeds that come from China or other foreign countries. Don’t even put them in the garbage. Destroy them or turn them in to the US Dept. of Agriculture.

Multiply by Division

Plants that grow from bulbs, corms or rhizomes, which are basically fat roots, can be easily doubled or tripled by dividing them after they have finished their growth season. Note: In most U.S. Southwest climates, it is not necessary to dig up and store these over the winter. Leave them in ground year ’round unless your garden experiences hard freezes.

Among the easiest to multiply by dividing is the drought-tolerant Bearded Iris (Iridaceae). Every 3 or 4 years simply dig up the rhizomes, trim the leaves back to about 5 or 6 inches, then cut the rhizomes apart with a sharp, clean knife. Allow the rhizomes to dry for a couple of weeks, then shallowly replant in late September or October. Don’t wait until Spring.

lily of nile canna lilies
Canna Lilies and blue Lily-0f-the-Nile Agapanthus.

When you divide Canna Lilies (Canna indica) there’s no need to dry out the rhizomes for weeks before replanting, but do wait until it has stopped blooming and the leaves have died down before you dig it up. After you’ve cut the rhizomes into pieces each with a short length of stem attached, let them sit for one or two days. Once the raw cut side has scabbed over you can replant.

Daylilies (Homercallis) and  Agapanthus also lend themselves to being divided. Again, dig them up, divide the large root ball clumps and replant. No long drying out period is required. You should do this every 3 to 5 years to encourage these plants to keep blooming beautifully. After replanting be sure to water them frequently until they are established.

Cutting it up

Take cuttings of your favorite lavender and replant. Bees will thank you!

You can multiply many shrubby perennial herbs, like salvias, rosemary, thyme, lavender, marjoram and oregano simply by taking a 4 to 8 inch long cutting of a stem with two to four leaves attached, then putting that stem in a pot of natural soil from your garden or use commercial potting soil mix. I prefer to mix native soil with potting mix. Take the cutting from fresh new growth for best results and keep the soil damp until ready to transplant into your garden.

You can also take cuttings from your favorite Geranium (Pelargonium) and simply stick them into a pot of soil or potting mix. Keep the soil damp and — voila — you will have vigorous new geraniums in bloom next summer.

working after retirement ebook and paperback

Garden Shows mean big savings on uncommon plants

Because people who belong to specialty flower clubs and garden clubs usually cultivate rare and uncommon varieties of plants, at their plant sales you are likely to find unusual hybrids and colors to add variety to your garden.

Check out nearby botanical gardens, too. They often have ongoing plant sales to help support their operations.

Because of Covid-19, however, this is not a good year to hold a neighborhood plant swap in your front yard or driveway. Garden club sales and Botanical Garden events may also be cancelled because of the pandemic.

Not So Perennial

santolina and petunias
The short-lived Santolina (Santolina incana)
with petunias in a flower border suitable for a
hot, dry climate.  The annual petunia will not
last long in hot summer weather.

Now many of these plants are ones we think of as “perennials”, but perennials are not really perennial. They don’t last forever. Over a period of 4 to 10 years you may have to replace every perennial in your garden so DIY frugal gardening can be a real budget saver.

Some perennials don’t even last that long. One of our favorite plants for a perennial flower border in a hot dry garden is the Santolina. I love its brilliant yellow ball-like flowers but it rarely lasts more than 2 or 3 years and then must be replaced to remain beautiful.

And Finally: A Wake Up Call

And remember, it’s best to plant in Fall when the average daily temperature falls below 90F (32C). After all, that’s when Mother Nature plants her seeds. And plants that survived this summer’s blistering heat and have been in summer dormancy are now waking up and they are hungry. Feed them well in the next few weeks so they will be strong and not need replacing next year.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

Saving a garden in relentless heat

As of today Tucson has suffered under daily high temperatures over 105F (44.5C) for 39 straight days. And the TV weather lady tells us these conditions will keep on going. No monsoon rain relief in sight in this part of the Sonoran desert. A friend in Las Vegas tells me it is as bad up there in the Mojave desert.

While this persistent heat is awful for humans, we can take shelter in air conditioning. Plants in the garden, however, cannot. So, what to do to help your plants survive this–or any other–extended period of heat?

The first thing that may come to mind is to increase watering the garden. Sadly, deep watering plants may or may not help. With day-after-day of temperatures of 90-100F+, some plants, particularly non-desert plants, cannot absorb water faster than it is evaporating through the plant’s leaves. Death by dehydration results.

Here, however, are 3 ways to help your plants survive until Fall.

Shade Cloth is a quick remedy

tucson tree under shade cloth
Photo Copyright by Tiffany Weerts 2020. An improvised shade cover in Tucson during a long hot spell.

Shade cloth is a fast solution for plants that appear to be suffering from heat exhaustion. You can buy it today, hang it up over vulnerable plants or borders in your garden and the protection starts immediately even if you have to just tack it up in a temporary make-shift way. Shade cloth comes in variety of weights and with UV protection.

Double pot to cool roots

For the plants that are in pots the heat and afternoon sunlight can be especially brutal. Placing pots where they will be in shade for most of the day is a recommended, but that may not be enough. Again, the problem is death by dehydration–water evaporating too rapidly through the leaves and from the potting soil. Compounding that problem is that terra cotta and metal pots heat up and can “cook” the roots.

Keeping potted plants in shade can help them survive, but double-potting increases the likelihood of the plants surviving summer heat.

However, one way to help your potted plants survive on the patio in summer is to set each pot in a second, larger container. Then put an insulating layer of dried moss or coarse organic mulch between the two pots. This will keep the inner pot cooler and protect plant roots from sizzling heat. You may want to try to keep the insulating layer damp–but beware of soaking it because the water could pool inside the outer pot and soak up into the inner one. You could end up drowning the plants from the bottom.

Consider using one of the newer plastic pots as your outer pot. They are far more attractive than they used to be and conduct far less heat than terra cotta pots. The insulation may also be helpful in winter, if you live in an area where it freezes in winter.

Visit my author’s site to see books I’ve written
and read a chapter of the children’s book free

Controversial polymers

Polymers, those water-retaining gel crystals, are frequently used in flower pots to help cut down on watering and retain water in the soil for the plants’ use. This isn’t an instant solution, but polymers can help over a longer term–like all those hot days ahead of us here in the Sonoran and Mojave deserts.

Recently, however, we heard a gardener advocate using water-retaining polymers in flower beds and in the soil around trees.  It sounded like a good idea — particularly in a climate where water evaporates out of the soil so rapidly.

But a little online research revealed a preliminary study which indicates that polymers may break down in our native soils into chemical components which may not be all that good for plants and people. So while polymers may be a great solution for flowering ornamental plants in pots, stick with adding organic amendments, such as crushed pecan hulls or finely ground wood chips, to your garden’s natural soil to increase its water-retaining ability. Moreover, organic amendments add nutrients to the soil, which polymers don’t. If you would like to review the research yourself, to go Google and search for: “Polymers Gardening.”

And if the heat kills most of your plants–which is happening in many gardens here in Tucson now–you can replant in late September or early October.

working after retirement ebook and paperback

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

What NOT to plant for fire season

I have always loved what I call the “Tucson Gardening Style“. No broad swathes of grassy lawn browning in the sunshine. No water-guzzling attempts at English flower garden borders limp and dying in the heat. Just native plants left where they were growing before any house was built: prickly pear cacti squeezed side-by-side with creosote bushes and saguaros and agaves and chollas and mesquites. And most of the time these Sonoran desert natives grow right up to the side of the house.

But on June 5th, after the Bighorn wildfire burst into life north of Tucson, this native plant gardening style suddenly seemed less charming and more threatening.

At first the Bighorn fire was just billowing smoke high up in the Santa Catalina Mountains. By June 9 when I drove around northern Tucson to to take photos for another blog, I began to realize an inferno would result if this fire reached down into the upscale Catalina Foothills neighborhood which had only hours before been designated as a threatened evacuation zone.

As I took a few pictures I also realized that in California, where I used to live, the “Tucson Gardening Style” would bring the fire service knocking at the door armed with chain saws and big fines. The law in California is that there must be a 100 foot cleared open space around a home and it is aggressively enforced.

There is, however, such a live-and-let-live “Nobody’s going to tell me what to do” outlook by many Arizonans that it is unlikely that type of regulation would ever be passed here.

Okay, while I live in Arizona now I’m going to ignore local attitudes regarding plants because wildfires happen here and throughout the Western United States. Here are some recommendations about garden plantings to help prevent your home turning into an pile of burnt rubble from an urban or wild fire.

First, clear plants away from the sides of your home and other buildings. Don’t let any shrubs or trees touch or almost touch a building. If the plants catch fire — even if ignited by sparks from a neighbor’s BBQ instead of a wildfire–your home could burst into flames before you even notice it.

While many trees suitable for hot dry climates have oily leaves, the Australian-native Eucalyptus trees are among the worst. Sure, they smell so good, but they are 50 foot high torches just waiting for a little spark to light them. As much as they seem to be great trees for hot dry climates (fast growth, low water usage, lovely dappled shade), they are not. As witness: the massive fires racing through the Eucalyptus forests of Australia in recent years.

I have also seen palm trees burning as 50 foot high torches in Los Angeles during an urban fire, but while embers fell from the palms, they did not seems as potentially dangerous as a flaming eucalyptus with its branches whipping in the wind casting sparks all over the area.

For very a different reason don’t plant a Cottonwood, a major water-sucking plant. Again, it is a fast grower, but will guzzle every drop of water in the ground around it and deprive other plants of water, leaving them tinder-dry. Cottonwood roots will also invade your plumbing and septic systems.

One grass is on the Do Not Plant list:

Buffelgrass (Cenchrus ciliaris L., or Pennisetum ciliare L.) is often called white fountain grass. An African native, it grows and blooms quickly, then dies back to leave dry, quick-burning fields waiting for a lightning strike to start burning. This grass, a threat to native plants including Arizona’s famous Saguaro cactus, has been mentioned as a key factor in the origin of the Bighorn fire. You can view a new webinar on the topic of buffelgrass damage to the Saguaro National Park .

Red Fountain grass does not spread wildly like White Fountain Grass. And it looks lovely when the wind blows.

Instead of Buffelgrass, consider Red fountain grass (Cordyline) which is less invasive and stays where it is planted. The much larger South American-native Pampas grass (Cortaderia selloana) will also stay where it is planted in a desert climate, but not if there is a pond or stream nearby. In that case it becomes invasive forcing out native plants.

Visit my author’s site to see books I’ve written
and read a chapter of the children’s book free

Now onto something more positive. While the evidence is anecdotal, a few homeowners have sworn that their huge water-logged agaves saved their homes during a wildfire. I’ve seen the photos and the agaves encircling the homes look as if they have melted, but the houses were spared. It’s important to note that there was a cleared space between the house and the agaves and beyond the agaves, too.

As for planting any trees or agaves, wait until fall. It is too hot now and there is a great risk that anything you plant will die of heat at this time of year no matter how much you water it. Don’t let the landscape guy tell you otherwise!

The Bighorn fire is still burning on June 19th, but because of a wind shift, it is moving northeast, away from Tucson proper. A photo of it taken yesterday is at the top of this post. According to reports over 3,000 Saguaros have already been destroyed, but–happy news–most of the wild animals in the fire path, including baby mountain goats, have escaped. And there has been no loss of homes or human life so far.

Here is what happens to an SUV when the Forest Service makes a Phos-Chek drop. It’s that red stuff fixed wing airplanes drop on the edges of fires.

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat

Adios Lantana. Hello potatoes!

NOTE: this is somewhat apocalyptic, but there is a bit of humor at the bottom.

Until recently, prepping for the apocalypse seemed to be a fringe activity. It kept a few people busy stashing fairly expensive survival gear in their basement survival shelters. Some preppers even got reality TV contracts which probably helped pay for those high priced guns and goodies.

Since the arrival of the coronavirus, however, and especially since the shut-down of midwest meat packing plants, more and more people–me among them–are considering planting a “survival garden”. Prepping now seems a realistic activity as significant disruption of the food distribution channels suddenly is a real possibility. It’s a complicated issue but here is an article that explains how food disruption is already happening in the U.S. and around the world.

tomatoes on vine

Now I’ve never been a big supporter of homeowners trying to grow vegetables in a hot dry desert-like climate. It takes a lot of effort, water, raised beds, shade cloths, soil amendments or even the entire replacement of lousy alkaline desert soil to grow veggies in a hot dry garden.

Even with all that I’ve heard disappointing tale after disappointing tale from gardeners who tried to do it. The costs are very very high, especially when calculated at the total dollars spent to produce each tomato or cantaloupe or bunch of spinach.

I’ve always thought: it’s better to support organic farmers by buying their vegetables at the grocery store. As we all know it costs a great deal of money to grow organic vegetables which is why they are more expensive than regular store-bought veggies. Even then, vegetables and fruits from organic growers are less expensive than growing your own in your backyard.

Visit my author’s site to see books I’ve written
and read a chapter of the children’s book free

I’m beginning to rethink this

root vegetables

Here is what I am going to do: rather than going the big raised bed or full backyard garden routes, I decided to start small and checked on Amazon to find grow bags, especially potato grow bags. My reasoning is that people–think of the Irish back in the 1700s and 1800s–lived almost entirely on potatoes. Not a balanced diet, but nutritious enough to survive for awhile.

Other below-ground vegetables, including carrots, parsnips and onions, as well as herbs and even tomatoes can be raised in grow bags.

potatoes on soil dirt

Then today I learned this lesson: what grows reasonably well in one hot and dry location won’t live in another. Summer, I discovered, is not a good time for potatoes in Tucson. Sweet potatoes are a possibility, however.

I’m going to have to do more research on what vegetables might grow in Tucson’s version of a hot, dry climate with its monsoons. Cantaloupes and squash are possibilities, I think. But when the weather cools I’m going to plant potatoes. Yukon Gold potatoes to be more specific. In a grow bag or a very large plastic pot.

Now I’m not advocating that you start a “survival garden”, but it seems to me to be worthwhile considering because now, more than ever in my lifetime, the future and the food supply seem very uncertain.

I’m not, however, going to remove the Lantana in my front garden right away and plant potatoes instead. Grow bags on my backyard patio are going to be my “survival garden”.

OK Here is a funny for you.

For art lovers: Tussen Kunst & Quarantaine (@tussenkunstenquarantaine) • Instagram photos and videos

Read our 8 most popular newsletters

  1. Hot Days, White Nights, How Design a Moon Garden
  2. Australian Plants for a Desert Garden
  3. Cover up that naked wall
  4. Best and beautiful native shrubs for extreme heat
  5. Five fragrant plants for your garden
  6. Where to get free or cheap trees for your garden
  7. Four desert trees good for soil, 4 toxic ones
  8. Plants that bloom even in mid-summer scorching heat