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Friday, May 22, 2020

"Red Push' Chinese Pistache for Residential Landscape

Q. We Live in the Phoenix, Arizona area and have two 10'x10' planters made of pavers and want to plant ‘Red Push’ Chinese Pistache in them. I am worried about damage to pavers from the roots. Irrigation would be from drip irrigation system on a timer.
One of the planters for a Chinese Pistache tree

A. ‘Red Push’ Chinese Pistache tree can get 50 to 60 feet tall with irrigation. In my opinion, this tree is too tall for most residential properties. You need a large landscape, a park or city streetscape to accommodate that size.

Read what Chris Martin from ASU has to say about Chinese Pistache in the Phoenix area.

The size of the planters should not be a problem when planting Chinese Pistache if using a soil coarse textured enough for good drainage and not planting shallow rooted flowers in there that require frequent, light irrigation. If planting something else in that planter, select plants that have deep roots or that don’t require frequent irrigation.

I would select a smaller tree. I have the feeling you selected that tree because of its fall color. There are other reasons for tree selection than just one trait. What sizea tree is needed for those planters? 20 feet? 30 feet? Remember, larger trees usually use more water. What shape should it be? Arching? Round? Upright?

The Phoenix area has some pretty good wholesale nurseries that grow plants for the desert including Mountain States Nursery and Arid Zone Trees. Take a look at what they have to offer.


Thursday, May 21, 2020

Desert Horticulture Podcast: Thinning Fruit

Thinning fruit, or fruit removal so the remaining fruit become larger, does not have to be a mystery. It is a management process that you must do for most fruit trees. If you don't, the remaining fruit will not become larger. But on some fruit trees it doesn't work. Learn which ones it doesn't work on and why in this Desert Horticulture Podcast.


Wednesday, May 20, 2020

Desert Horticulture Podcast: Bottle Trees, Spider Mites and Yellow Plants in Desert Landscapes

Learn why Bottle trees are NOT desert trees, managing spider mites in home landscapes and the reasons for the yellowing of plants growing in desert soils.


Monday, May 18, 2020

Sunburn A Huge Problem in the Desert

Our light intensity is very strong in the desert. Some thin barked trees and shrubs get sunburned if they don't have enough protection from strong sunlight. The natural way to protect plants from sunburn is to allow these plants to shade their own trunks and stems with leaves. Not providing enough water can thin out the canopy of trees and shrubs and encourage sunburn.
Sunburn, like on this ash tree, starts out as a discoloration of the wood.
Plants that typically sunburn include many of our fruit trees, mostly peach and apples. Ornamental trees and shrubs also get sunburn. Plants that I see with sunburn include Japanese blueberry, locust trees, ash trees, Indian Hawthorn, and others.
Sunburn can happen to fruit, too. This yellow apple has the first sign of sunburn on the fruit facing the sun.
Severe sunburn causes the plant to die on the side exposed to the sun. Bark on this side is loosely attached to the trunk. When you pull this bark away from the trunk you may see oval-shaped holes in the wood. These are exit holes of borers. Removing the bark also removes hiding places and birds have a better chance picking them off when they emerge.
The side facing the sun dies under severe conditions and boring insects can invade the living parts on the edges of the damage. Eventually this becomes part of the tree that dies.
Having rock mulch around plants that do not like rock mulch reduces the number of leaves and increases the chance of sunburn. Plants that do not like rock mulch, like the ones I mentioned above, will develop an open canopy, leaf loss, and sunburn.
In the case of sunburned fruit the area darkens as the sunburn worsens.
What's the problem with sunburn? When humans get sunburn we recover. When plants get sunburn, particularly in a desert climate, they frequently decline and die. Attack by boring insects, or borers, is the first phase after sunburn damage. The borers create more leaf loss which increases sunburn. At this point the plant falls into a death spiral.
The side of the branch or trunk facing the sun has the most damage. In this Bottle tree it is the upper surface of the limbs.
Use surface mulch, particularly wood chips, and not bark mulch. Don't water trees and shrubs daily. Water them two or three times each week during the heat of the summer. Reduce the number of times per week during the cooler months. When they receive water, it should water the roots to a depth of at least 12 and preferably 18 inches.

Message to Landscape Maintenance Contractors and Homeowners

As I was walking my property, I was thinking about landscape maintenance contractors and what they should be doing when going from job to job. As I thought about it more, I realized it would be a good message to homeowners as well.
Alcohol wipes are safe and easy way to sanitize pruners.


Sanitize Pruning Equipment

Tree and plant diseases like Sooty Canker and Fireblight and, who knows even though its not proven, Ash Decline. We know that many plant diseases are passed along from plant to plant and residence to residence by unsanitary equipment, hands and clothing. Sanitize your pruning equipment between residences. If you see a plant or tree that you are trimming and it doesn't look right, SANITIZE any pruning equipment you use on it. Then educate your customer. Let them know you are doing it and why. Make it a difference between your company and another who doesn't know or, worse yet, doesn't care!

BTW, most tree diseases are spread when the tree is actively growing so a good time to prune is during the winter months. ALWAYS sanitize your tools when plants are growing.

Sanitize Mowers

Besides lawn diseases, lawn weeds can be passed on from property to property on unclean mowers. Everyone is using a mulching mower now but they still need to be cleaned, particularly when a disease is active. Our lawn diseases are mostly "hot weather diseases" like Summer Blight. Many of our worst weeds I hear complaints about are "winter weeds" like Poa annua. Spreading lawn diseases and weeds lasts 12 months long. Ask to use your customers hose and wash mowers between jobs, Turn the mower over and spray the blade with a sanitizer before the next job.

Handling Your Boss

More money is a good incentive. Instead of being the "tree hugger" or "plant person" on a job, use the money angle. Charge a little more for the work you do. Or tell them it will reduce costs. It costs a bit more to sanitize your tools and equipment but your customers will pay for it. As I always tell my students, "Pursue the HIGHEST dollar you can get, not the LOWEST!" Charge for your time and let the customer know you are doing something about the spread of plant diseases and weeds.

Sunday, May 17, 2020

Know the Difference Between Carolina Laurel and Bay Laurel

Q. I found your blog, Xtremehorticulture of the Desert, and hoping you can tell me if my tree is a Bay Laurel or not. I looked at pictures of Carolina Cherry trees that look similar. This tree has supports which I know need to be removed at some point. The tree was planted by my builder in February of last year.
Bay Laurel just after we pruned it

A. Looks like Bay Laurel to me. Bay Laurel is a Mediterranean tree and more tolerant of our desert climate than Carolina Cherry Laurel. Carolina Cherry Laurel is native to the southeastern US and not tolerant of desert conditions without proper site selection, soil preparation and watering.
Carolina cherry laurel is native to the SE United States so it struggles when planted in hot locations with inhospitable soil. This one is suffering from iron chlorosis.


            One easy way to tell the difference is to crush the leaves and smell the herbal (Bay) aroma.  Bay Laurel leaves have a pungent aroma. When you crush the leaves of Carolina Cherry Laurel they have an aroma of maraschino cherries rather than herbal.

            The second way is to look for round “glands” at the base of the Carolina CherryLaurel leaf where the leaf is attached to the petiole (leaf stem). These “glands” are characteristic of many plants in its genus (Prunus) like plums, cherry, peach, etc.
            In 98% of the cases, the “supports” or stakes should be removed after one growing season. There are a few cases when the trees do not establish rapidly due to grower mismanagement or poor planting practices and need support longer than this.

Orange Palm Leaves Signal Time to Prune

Q. The bottom layer of my palm fronds turned an orange - yellow color almost overnight. Is this from too much water or not enough water?
Palm fronds may turn orange before they become yellow or brown and then die. Its your signal to prune.

A. Neither. The cause of these fronds turning orange or yellow is natural. These orange and yellow colors are already there, masked by the strong green color that the chlorophyll provides. We see the same color changes with “Fall color”.
Canary Island Date Palm with lower fronds dying naturally.
            The bottom layer of fronds die naturally. As these lower fronds approach death due to old age and shade, some of the minerals in the leaves are absorbed back into the palm, first turning the lower fronds orange or yellow and eventually brown. Sometimes these color changes occur quickly and other times more slowly. How fast depends on how hot it is.
Fan palm with brown lower fronds in need of pruning and removal.

            The nitrogen, phosphorus and potassium move out of the frond first followed by magnesium, chlorine, zinc and molybdenum. Lesser mobile nutrients are left behind which include sulfur, iron, boron, and copper. These mineral “remainers” dominate the content of palm fronds. This color change is your signal to cut and remove palm fronds.

Look for Borer Problems As it Gets Hot


            I had reports sent to me about peach trees with yellow leaves on a single branch. You might see this on other fruit trees such as apple as well. For those of you lucky enough to have this condition on your fruit tree then this may be an indicator of a borer problem that needs treatment now. Let us talk about what else to look for to confirm it and what to do.
Borer problem on the limb of a three year old peach tree.

            Notice I said, “yellow leaves on a single branch”. This is important because borers usually lay their eggs on a single branch, not all over the entire tree. The only exception is if your fruit tree is newly planted or less than two or maybe three years old. In this case, the borers may find the trunk of the tree enticing for egg laying and kill the entire tree outright. Usually borer damage is in full sun, on the south or west sides of the trunk.
Jelly-like sap oozing from the trunk or limb of a susceptible tree after a rain is a pretty good tell-tale indicator of borers. 

            Look for sun or borer damage to the limb with yellow leaves on its upper surface. Borers seldom affect the shaded sides of branches or on the north or east sides.
Borer damage to a newly planted tree can be lethal because the tree is so small.

            What to do? Buy an insecticide that contains imidacloprid listed in the active ingredients on the label.  Follow the label directions for a “soil drench” applied around the base of the tree where water is applied. You would do this now but I would treat the tree as a non-edible for the next 12 months even if the label permits its use on fruit trees.

            I have had some luck using a sharpened, sanitized knife without an applied insecticide. The knife is typically 6 to 8 inches long with a good-sized blade for removing the damaged bark. The damaged area is skinned away from the limb until fresh wood, not damaged by the borer, is seen. The damaged area cut away by the knife is only about ¼ inch deep. This cut area is not treated in any way but allowed to heal on its own.
I have had some luck using a clean knife and eliminating borer neighborhoods. I have no research to back it up but it seems to work sometimes.


Sucker Growth From the Base Can Signal Drought

Q. We have three Japanese Blueberry trees in our yard: two in the back and one in the front.  All three have dead branches that snap off when you bend them.  Yet there are scattered green leaves above the dead branches and far more green leaves at the bottoms of the three plants. Is it possible this is due to lack of water?  They were all planted about 4 1/2 years ago.
 
Some plants will die back and regrow from its base. This can be due to a lack of water or sunburn in high light intensity environments.
A. Sounds about right. Sounds like the trees went through a dry spell and then regrew. Oftentimes when trees come back from drought they sucker from the base. But some trees like oleander (grown as a tree, not a bush) will sucker from its base naturally because it wants to be a shrub. If the drought lasts quite awhile, the top can also die back. There are trees that sucker from the base naturally, but this tree shouldn’t unless it was stressed.
Japanese blueberry struggling in our hot, dry desert climate.

            Whatever caused the stress (you are guessing maybe a lack of water) suckers grew from the base of the tree. The top may have “fried” during the drought, and then grew leaves again, from leaf buds on the stem, when water was reapplied.
            You are aware that Japanese Blueberry is not a great choice for desert climates. It is not a “desert adapted” tree. Does great in coastal California but not the desert. Make sure the trees are planted in the mildest microclimate you have (probably east or north side of your home), the soil was amended at the time of planting, water applied under the canopy 18 inches deep and the top of the soil covered with woodchips and not rock.

Get free woodchips and load them in plastic bags, a car or a pickup truck. Call the Master Gardener helpline at 702-257-5555, M-F,  and see if any are available and where.

How Often to Water During the Heat

Q. How often should I water my trees and shrubs with all this heat. The weather got hot so quickly, I’m not sure when to water. I have a California Pepper Tree, two big palm trees and five Japanese boxwood shrubs.
California pepper tree that was planted too close to cement and so lifted it with its roots.

A. First off, don’t violate your water purveyors watering directions. These policies are in place to coordinate community water use and lower the costs of supplying water to end users like you. If you live in Las Vegas you can see it here.
            All the plants you mentioned are called “mesic” plants and require more frequent irrigation compared to (xeric) desert plants. The amount of applied water depends on the size of the plant. As plants get larger, more water is applied to a larger area (even though the water wets the same depth of soil) under the plants canopy.
Watering cacti too often can contribute to fast growth and so much succulence it cant stand up against its own weight.

            Apply water to all the area under the plants canopy. This advice might be difficult to do with larger trees like your California Pepper, so apply water to at least half the area under a plants canopy when they are big. This way they won't blow over as easily during a windstorm.
Watering frequently near the base of a plant can cause it to lose support during a windstorm.

            Lawns, annual flowerbeds and raised beds for annual vegetables require daily, or near daily, applications of water. Sometimes they need water twice a day. These plants should receive water that wets the soil to a depth of about six to 10 inches with each watering.
A piece of rebar can be used to judge how many minutes to water. Rebar pushes easily into wet soil.
            Shrubs and patio trees should be watered to a depth of 18 inches. Medium sized trees around 30 feet tall should receive enough water to wet the soil to a depth of 24 inches. Large trees need the soil wet to a depth of 36 inches after an irrigation.
            How to know if the applied water went deep enough? Use a straight, 4-foot-long steel rebar and push it into the soil after an irrigation. It stops going deeper where the water stops.
            How to water deeper with the same number of minutes? Add more drip emitters under the plant.

Hang Garlic in the Shade to Dry

Q. I recently harvested my garlic crop, wrapped it in burlap, and hung it up to dry.  How long should I let it dry in the Vegas heat? Last year I let it go for over a month and the bulbs got mushy.
Freshly harvested garlic.

A. If the bulbs got mushy then it was harvested too early or the bulbs stayed too wet. In our climate, don’t wrap garlic in burlap but dry it in the shade instead. I never had problems drying garlic. I leave the tops attached, bunch them together and hang them in the shade.
Chesnok Red garlic hanging in the shade to finish drying.

            To me, this seems a bit early to harvest garlic. My garlic was harvested in late May or June when the tops had dried back about 1/3 in the field. It is hard to tell without seeing them, but the bulbs should be fully developed when harvesting. Browning of the tops is a way to know if they are starting to mature or not. If you let the tops all turn brown then the “paper” wrapping around the bulbs will get damaged.
Polish White garlic growing in North Las Vegas.

            Garlic is planted in the Fall and harvested in early to mid-summer after the bulbs have formed. Shake the soil from the plants when you harvest, don’t wash them. I grew about 25 varieties of garlic and they all did well here. This is a good climate for garlic. So, keep an eye on the plants and harvest them when they are fully formed on their own and dry them in the shade.

My Santa Rosa Pollinator Died and I Have Pluots

Q. I have a 2-year old Flavor Supreme pluot and a four-year old Flavor King pluot. Recently my Santa Rosa plum (their pollinator) died from borers. The Flavor Supreme had only a few fruit while the Flavor King was loaded. Do I need to plant a plum tree to pollinate the Flavor Supreme? Or does it have a small number of fruit because it is only 2 years old? 
Ripe Santa Rosa plum ready for picking.

A. Flavor Supreme pluot has wonderful fruit but its production is sketchy because of spring freezes. So most likely the tree was thinned of some fruit by some late spring freezes. Plus, its only two years old! Some years Flavor Supreme may get no fruit even though it flowers because of a freeze. This is less likely to happen with Flavor King.

Flavor King pluot. Has a lot of plum in its genetics.

            Santa Rosa plum produces good soft fruit in our climate and is a good pollinator for most pluots. Flavor Supreme is a pollinator for Flavor King pluot as well. Throw Dapple Dandy pluot in that group as well. But pluots will still produce fruit without a Santa Rosa plum or pluot in your yard. Just possibly a lighter crop. If a neighbor has a Santa Rosa plum or Dapple Dandy pluot then it is to your benefit.
Flavor Supreme pluot


May is When Agaves Die


            I am getting quite a few emails about cacti dying, particularly agave. Some are guessing the culprits are ants, diseases and other readers appear to be stumped.
American Agave can die in about May of any year.

Agave Weevil

            The culprit is the agave weevil that lays its eggs at the base of agave leaves. As their young-uns hatch from the eggs, they burrow into the stem of the agave and all through it including the roots. The plant rots and dies from all the damage done usually in late April or May. We are seeing it now. A pesticide applied around its base in March, and lightly watered in, usually prevents the damage from getting worse. The other option is not to grow agave.
Agave weevils can decimate agaves in May if left unchecked

Drainage a Must

            If you’ve never grown any cacti before, make sure the soil drains easily of water and that don’t water these plants too often. I have found a deep watering every three weeks is frequent enough to push new growth and get the plants larger.

Know the Origin of Your Cactus 

Some cacti are not meant for very hot locations because they come from milder climates. Photo taken at the LV Sorings Preserve.
Some beautiful cacti and other succulents come from the hot, dry deserts of Central and North America. Make sure they are placed in full sun. Other cacti may come from milder, coastal or high-altitude desert climates and need protection from the intense Mojave Desert sun. Knowing where cacti come from empowers you and its landscape placement.

Reasons Why Meyer Lemon has Distorted Leaves

Q. I applied Bonide Tree and Shrub insect control for borers and miners about six weeks ago. Now my plants are growing weird and possibly dying. Once I saw this problem, I sprayed for diseases and then today for insects. What is going on?

Picture not available

A. The damage to the plant was probably weed killer (herbicide) damage judging from the distorted leaves and dieback. There is not much to do at this point except spray the foliage with water, irrigate, and make sure the plants were fertilized in the spring, so they are in their best health to recover as quickly as possible. Then wait and see what happens. There is no magic cure at this point except being patient for three or four weeks.

            Let’s cover some reasons why this might happen so it might be prevented in the future. The damage could have originated from you or your neighbors. This type of damage is a common occurrence during the spring and the fall months because these are the most effective times to apply weed killers.

Sprayer Not Rinsed

            First, never use a sprayer or spray bottle that contained weed killers to spray insects or diseases. You should have two separate sprayers or bottles; one clearly marked and used for “Weed Killers”. Weed killers are extremely difficult to clean from a sprayer or spray bottle once it’s been used for that purpose. If there is some weed killer residue that remains after washing, then voilĂ , you just damaged plants that you sprayed for controlling insects and diseases!

Spray Drift

            Secondly, you or your neighbors should never spray weed killers when there is wind. If you must use a weed killer, look at the tallest trees in the neighborhood and see if their leaves are moving. If they are, do not spray weed killers. The best time to spray weed killers is early in the morning before the wind has kicked up and it starts to get warm.

Heat

            The word “warm” takes me to the third rule; never spray a warm surface or when air temperatures are warm or hot. Landscape rock mulch heats up quickly as soon as the sun comes up. On a warm day, these surfaces reach 150°F or more by 9 AM on a sunny spring day. When weed killers are sprayed on hot surfaces, they volatilize and move to the neighbor’s yard with the gentlest air movement and can cause plant damage.

Growing Peppers in Containers in the Desert

Q. I am growing hot peppers in big plastic pots with soil for vegetables I bought from a local nursery. The plants grow fine but the blossoms dry out and fall off without setting any peppers. They get plenty of water, not too much, and the bottom of the pots are drilled out for drainage.
Soil mixes like this Rejuvenate Soil Mix should have quite a bit of compost mixed in it for growing vegetables.

A. Growing plants in pots is difficult in the hot desert. The major problem is overheating of the soil. The side of the container facing the sun can reach 170° F and kill half the roots inside. Losing half the roots of a plant can be quite stressful and cause flower drop. You can kill a lot of roots with a bad soil mix, poor drainage and watering too often, but it doesn’t sound like that’s what’s happening.
Five gallon nursery containers are big enough if you water early in the morning and they are on the east side.

 Make sure the container is large enough. Five-gallon nursery containers are large enough if plants are watered daily, sometimes twice a day when it’s hot, and the soil stays cool. I have had luck with this size container growing vegetables and herbs if on the east side of a building so the container is shaded in the afternoons. Containers may be shaded by other containers or a vegetable bed. But larger, 15-gallon containers work better.
A single cabbage growing in a five gallon nursery container

            Water just before the container gets hot. Moist soil is harder to heat up than drier soil. This is because the water in the soil absorbs heat. I will usually water between 7 and 9 AM.
            Double pot the container. Putting the growing container inside an outer, more decorative container shades the inside container and protects plant roots. This is called “double potting” or “pot-in-pot” container growing. If the containers are the same size and shape, put a layer of pea gravel 2 inches deep in the bottom of the outside container so they don’t lodge.
            Plants grown in the double containers for more than one growing season should be twisted a half turn every month to break off roots growing through the container into the ground.

Ocotillo Doesn't Need Misting After it is Established

Q. I have an Ocotillo plant that is now sprouting beautiful flowers and leaves. I have been watering it with a mist spray near the top. Now that it is in full foliage can I turn of the mist and just water at the base once a week?
Ocotillo and myoporum went through a rough winter in 2013. This was probably January after a good freeze.

A. I have never been a big fan of misting plants like Saguaro, Joshua Tree or Ocotillo. It doesn’t hurt anything, but personally I think it’s a waste of time. The effects of misting last less than 10 minutes in the desert. Ocotillo stem cuttings will grow roots in soil that drains without any misting if they are watered regularly in the spring.
Ocotillo growing in the Sonoran Desert. Although not found in the Mojave Desert, Ocotillo can be found on the edge of the Sonoran and Mojave Deserts nor far from the Colorado River.
            Now that the leaves are out, turn over the watering to the roots. If it is newly planted, moisten the soil each time you water close to the trunk or stem. A basin or donut constructed around the trunk helps contain the water. Fill the level basin with 1 to 2 inches of water each time you water. Remember, these are desert plants so don’t water them as often as non-desert plants. If you do, you can kill them.
A good sized Ocotillo growing at a Las Vegas residence.
            In about one month, increase the size of the basin or apply the water over a larger area to encourage the roots to grow further distances from the trunk. Watch the growth of your plant. Adjust your watering intervals to encourage or discourage growth.

Blackberries for Southern Nevada

Q. I received a Thornless Blackberry plant as a gift from an online nursery. Can I grow this blackberry bush in our yard? We have lots of rabbits and birds visiting all the time.
Blackberries growing in NLV Nevada at the University Orchard. This was either Rosborough or Womack. They are very similar.

A. I have grown blackberries in the Las Vegas Valley. Some varieties of blackberries perform better in the Eastern Mojave Desert than others. Some varieties struggle with poor growth and scorched leaves in our climate and soils while others don’t have the same issues.
Either Rosborough or Womack at the University Orchard.

            You don’t mention which variety you have, but I had success with 'Womack' and 'Rosborough' varieties out of the Texas A&M breeding program but not 'Brazos' which came out of the same program and was successful in Florida. I have had poor luck growing any varieties coming from the Arkansas breeding program. They mostly have Native American names like 'Arapaho', 'Apache', 'Comanche', etc.
Rosborough or Womack blackberry at the University Orchard in NLV, Nevada.

Aside

Blackberries are divided into trailing, semi-erect or erect types. These blackberries were semi erect so I had a wire trellis for them mostly to keep them upright. Blackberries can also be divided into thornless or ouch. Mine were ouch! They definitely had thorns. I learned to prune them soon after harvest because it was difficult to figure out which ones had berries that year (floricanes) and which ones I needed to leave for next years production (primocanes). The canes would grow a little over five feet tall and they were flooded in a sunken irrigated bed with bubblers. After I left, the Orchard manager tried to pull them out but there were still some root remnants in there a few years after I left.

            Don’t expect the same quality berry as you might get from the Pacific Northwest and they don’t keep as long in our desert heat of May. Blackberries will be ready to pick in one day rather than two or three days as they are in cooler climates. This means, like figs, you must check blackberries every day when they are close to mature.  
Womack blackberry at the University Orchard probably close to May, 2004
            I would grow blackberries as a novelty but don’t expect miracles. Amend the soil with good compost at planting time and water regularly. 

Cooperative Extension at Arizona State University prepared an online fact sheet on blackberries from some research done in Yuma, Arizona. 

Butterfly Plants for the Desert

Q. I want to give my son a housewarming gift of a Butterfly Bush for his new home in Summerlin. Would there be any special care for growing that bush here?

A. I think you are referring to the Butterfly Bush, Buddleia davidii. This plant is grown successfully further north, commonly in the Northeast, mid-Atlantic, and Midwestern states. It is meant to be grown in cooler, wetter climates and not intended for the desert. Will it grow here? Probably, if you plant it in the cool microclimate part of the landscape and give it some TLC.
            There is another Buddleia, Buddleia marrubifolia, and called the Woolly Butterfly Bush, that does do well here and is attractive to butterflies but may be hard to find.


            In the desert there are better choices for attracting butterflies, if that is your intention, including Jojoba, any of the native Senna, Bottlebrush, Saltbush, Lantana, Goji or Wolfberry, Red Bird of Paradise and many others.

Arizona Plant Lady on Butterfly Gardens

University of Az on Butterfly Gardens