Alternative fruit trees for the desert

Pomegranate

Growing standard fruit trees in the low desert is challenging. Stone fruits, such as peaches, plums and apricots, require a certain amount of cold (called “chilling hours”) to produce fruit. Even “low chill” varieties may not fruit in a mild winter. Part of the problem, aside from chilling hours, is our fickle winters. A warm spell in January can prompt flowering, only to have the flowers killed by a February frost. And although citrus trees do not require chilling hours, they are high water consumers and need protection from heavy frosts all winter. If you don't want the fuss, here are a few fruit tree alternatives that are less water greedy and still produce tasty fruit. They are also attractive and functional plants, too.

Pomegranates have now become quite the rage because of the fruit's health benefits. The fruits are quite expensive in stores, so what a great bonus to grow your own! Even better: pomegranates start producing fruit even where they are only a couple feet tall.
Pomegranates do very well in the desert. They love our alkaline soil. They are very drought tolerant, but do need a little extra water while they are fruiting so the fruits don't split open. They make a lovely large shrub or small tree. Their flowers attract hummingbirds, too. Keep in mind they are deciduous. 

Another plant that does quite well here is the Pineapple Guava. This is an attractive, evergreen shrub or small tree with gray-green leaves that are white on the underside. The flowers, which are edible, are a pretty pinkish to white with distinctive red stamens. The fruit ripens from late fall into December. Don't pick them off the tree; they are only ripe when they fall to the ground. The fruit resemble kiwis, but are tart, and taste a bit citrusy.

Loquats are another option. This evergreen tree of small stature is unusual for a desert plant since it has very large leaves. These leaves are covered with fine hairs that protect it from the heat by reflecting off the intense suns rays. Loquat fruits ripen in the spring, and taste somewhat like apricots. It is also somewhat drought tolerant.

If you just gotta have oranges, why not try the Kumquat? The Kumquat is the citrus industry’s attempt at creating a cold hardy citrus tree. While they didn’t catch on as they’d hoped, they are available for purchase. Kumquats are more cold tolerant than regular citrus trees, but will still need protection if temperatures drop into the 20’s. The fruits are tiny, an inch or so long, and should be eaten without peeling, as most of the sweetness is in the peel.

Do you really need to know those Latin plant names?

Acacia constricta (Whitethorn Acacia)

Have you ever wondered what those tongue twisting Latin plant names mean? Although they may look daunting to pronounce, they actually have a rhyme and reason. Here are a few examples of how to decipher the scientific name of plants and why it pays to know.

Plant names are based on genus and species, specifically referencing a certain plant and recognized everywhere as that plant. Common names are confusing and not accurate; a plant may have several different common names, but only one scientific name. This can have you walking out of the nursery with the wrong plant.

Latin names are descriptive of the plant’s appearance, or in some cases where it comes from. Mexicana in the name means it is from Mexico. Whitethorn acacia, one of our native plants, is called Acacia constricta. It is in the genus Acacia, and the species name, constricta, references the seed pods with deep constrictions between the seeds inside, separating each seed into a chamber.

Many Latin names give you an indication of flower color. For example, plant names with the word alba or albus means they have white flowers or other plant parts. Incanus means gray or hoary; like Poliomintha incanus, which is hoary mint, one of our desert native shrubs. Plants with yellow parts will have names such as citrinus, corceus and luteus.

It pays to know the Latin name over the common name especially when you are selecting plants a bit out of the ordinary. That way you are sure you are getting the exact species you think you are.

Do you really need to know those Latin plant names?

Acacia constricta (Whitethorn Acacia)

Have you ever wondered what those tongue twisting Latin plant names mean? Although they may look daunting to pronounce, they actually have a rhyme and reason. Here are a few examples of how to decipher the scientific name of plants and why it pays to know.

Plant names are based on genus and species, specifically referencing a certain plant and recognized everywhere as that plant. Common names are confusing and not accurate; a plant may have several different common names, but only one scientific name. This can have you walking out of the nursery with the wrong plant.

Latin names are descriptive of the plant’s appearance, or in some cases where it comes from. Mexicana in the name means it is from Mexico. Whitethorn acacia, one of our native plants, is called Acacia constricta. It is in the genus Acacia, and the species name, constricta, references the seed pods with deep constrictions between the seeds inside, separating each seed into a chamber.

Many Latin names give you an indication of flower color. For example, plant names with the word alba or albus means they have white flowers or other plant parts. Incanus means gray or hoary; like Poliomintha incanus, which is hoary mint, one of our desert native shrubs. Plants with yellow parts will have names such as citrinus, corceus and luteus.

It pays to know the Latin name over the common name especially when you are selecting plants a bit out of the ordinary. That way you are sure you are getting the exact species you think you are.

Are you under or over watering your landscape plants?

Growing plants in the desert is challenging all the way around; from the heat to cold to minimal rainfall, getting plants to thrive can be frustrating. If you are puzzled as to how to tell if you are over or under watering your landscaping in the desert southwest, here are some guidelines.

It is frustrating to try and figure out what your plants want, as by the time they show symptoms in many cases, it’s too late to save the plant. Do not wait too long, however, or you may lose most of your plants.

Under and over watering symptoms often overlap, creating even more frustration. Evaluating symptoms carefully, however, will guide you in the right direction.

Under watering symptoms include loss of plant vigor, wilting, yellow leaves, leaf curling or drop, pest attack, stem and branch dieback and eventual death. Over watering symptoms include leaves yellowing, leaves smaller than normal, chlorosis (both iron and nitrogen), slow decline, soil-borne pathogens, and eventual death.

If your home was built within the past few years, chances are pretty good your irrigation timer is set for initial planting. After the first few months, the irrigation system should have been rescheduled. In this case, almost guaranteed your plants are being over watered. If you are a minimalist and either don’t have an irrigation system or try to water by hand, chances are pretty good you are not watering enough or deep enough.

Although desert plants are drought and low water specialists, most do need some periodic irrigation to look their best. Just don’t kill them with kindness (water).

It's time to adjust your irrigation schedule

As we approach November, it’s getting close to time to reset irrigation controller. Why should you bother? Wasting water never makes sense. The average home in my community uses 200 gallons per day. It may not sound like much, but add that up over a year, and that’s 73,000 gallons. Forty percent of that is typically for outdoor watering. That’s nearly 30,000 gallons per year. With the water situation here at critical levels, it makes no sense to water plants when they don’t need it.

Days are getting shorter and cooler, so plants require less water. Irrigation of desert adapted and native plants can go to once a week starting in late October. For well-established native plants (at least 3 years old) you can back off to twice a month.

There is one caveat to this, however. The only way you can change your watering schedule is if you have been watering correctly from the start. This means deep watering so the entire root system gets a good soaking. If you have been engaged in shallow watering, the root system will not be as drought tolerant, and the plant may show signs of stress if you back off.

So how to change this? Start watering your plants deeply and slowly, and over a growing season (through next summer) you will be able to adjust your irrigation in the winter months to save water. The truth is, a vigorously growing landscape plant is not happier. Studies have proven moderately stressed plants, plants that are not watered and fertilized regularly, are less prone to insect pests and disease.

Planning a new garden: location, location, location!

So you want to start a garden. Congratulations!

First up, you’ll need to consider orientation, soil type and physical location. Preferably you want an area that is not too rocky and relatively flat. It should be near the house, but not too close as the garden is not always picturesque and can be odorous if you are using steer manure. You DO want it near enough that it is convenient to bring produce into the kitchen. The garden will need at least 6 hours of sunshine per day and afternoon shade, whether you take advantage of a tree or building, or are planning on putting up shade cloth.

The next consideration is size. If you are limited for space, make it as large as you possibly can as you will want to be able to rotate your crops; especially tomatoes and peppers, which are susceptible to multiple diseases and should not be planted in the same place for at least 3 years. 

Raised beds are an option if your soil is just too rocky, or if caliche is a problem in your area. Keep in mind several things. Raised beds dry out quicker so you will be watering more often, you will have to import top soil to fill them (and make sure it really is top soil as otherwise you will end up with excavated soil that has no nutritional value), you will have to be careful about using treated lumber for the edges as it contains arsenic. Concrete blocks will leach lime into the bed, and plants don’t like that either. You will also probably end up turning the soil by hand, as it is difficult to rototill inside a raised bed. My preference is to just work with what you have, but there are cases where raised beds are the only option.

The garden will need to be fenced against rodents and snakes, and if you are in a very rural area also javalina and deer. Even if you have a fence or wall, keep in mind that ground squirrels can climb walls and ground squirrels, rabbits and javalina will dig under fences to get after your garden bounty. Some snakes can climb fences and walls, so they need to be tall enough to discourage this. Snakes can slip through a 1” opening, so you will need to secure the gate openings as well.

If you live in an area where rabbits, ground squirrels and snakes have the potential for being a problem, you will need to erect a fence at least 4’ tall. Use fence with 2” x 4” openings, and add 3’ tall ¼” hardware cloth or ½” chicken wire to the fence, burying at least 12” underground, and bending at least a few inches of the bottom into an L shape, to deter rodents from digging under. If javalina are a potential problem, you will need to reinforce the bottom of the fence with barbed wire. If deer could be a problem, your fence will need to be 8’ tall.

Also keep in mind where you will be storing composting materials. If you plan on obtaining large quantities of animal manure or storing straw and other composting supplies, you will need a place where a vehicle can access, and close enough to the garden so you aren’t making tons of wheelbarrow trips. You also don’t want it to offend the neighbors, so try to keep it out of sight, if possible.

Planning a new garden: location, location, location!

So you want to start a garden. Congratulations!

First up, you’ll need to consider orientation, soil type and physical location. Preferably you want an area that is not too rocky and relatively flat. It should be near the house, but not too close as the garden is not always picturesque and can be odorous if you are using steer manure. You DO want it near enough that it is convenient to bring produce into the kitchen. The garden will need at least 6 hours of sunshine per day and afternoon shade, whether you take advantage of a tree or building, or are planning on putting up shade cloth.

The next consideration is size. If you are limited for space, make it as large as you possibly can as you will want to be able to rotate your crops; especially tomatoes and peppers, which are susceptible to multiple diseases and should not be planted in the same place for at least 3 years. 

Raised beds are an option if your soil is just too rocky, or if caliche is a problem in your area. Keep in mind several things. Raised beds dry out quicker so you will be watering more often, you will have to import top soil to fill them (and make sure it really is top soil as otherwise you will end up with excavated soil that has no nutritional value), you will have to be careful about using treated lumber for the edges as it contains arsenic. Concrete blocks will leach lime into the bed, and plants don’t like that either. You will also probably end up turning the soil by hand, as it is difficult to rototill inside a raised bed. My preference is to just work with what you have, but there are cases where raised beds are the only option.

The garden will need to be fenced against rodents and snakes, and if you are in a very rural area also javalina and deer. Even if you have a fence or wall, keep in mind that ground squirrels can climb walls and ground squirrels, rabbits and javalina will dig under fences to get after your garden bounty. Some snakes can climb fences and walls, so they need to be tall enough to discourage this. Snakes can slip through a 1” opening, so you will need to secure the gate openings as well.

If you live in an area where rabbits, ground squirrels and snakes have the potential for being a problem, you will need to erect a fence at least 4’ tall. Use fence with 2” x 4” openings, and add 3’ tall ¼” hardware cloth or ½” chicken wire to the fence, burying at least 12” underground, and bending at least a few inches of the bottom into an L shape, to deter rodents from digging under. If javalina are a potential problem, you will need to reinforce the bottom of the fence with barbed wire. If deer could be a problem, your fence will need to be 8’ tall.

Also keep in mind where you will be storing composting materials. If you plan on obtaining large quantities of animal manure or storing straw and other composting supplies, you will need a place where a vehicle can access, and close enough to the garden so you aren’t making tons of wheelbarrow trips. You also don’t want it to offend the neighbors, so try to keep it out of sight, if possible.

A primer on biological insect controls

Bt works wonders on the tomato hornworm

There are a number of products on the market that advertise they are biological insect controllers, and it is important to understand how some of these products work. Just because a product is made from natural ingredients, does not mean it is necessarily non-toxic or safe for the environment. 

For an organic garden, you need to keep in mind what your priorities are. If you do not want to use any pesticides what-so-ever, then handpicking bugs and barriers (such as floating row covers) may be your best options. There may come a point when you need some help, and there are products out there that can do that for you.

BACILLUS THURINGIENSIS

I am a big proponent of Bt (Bacillus thuringiensis and its counterparts) as it is totally biodegradable, non-toxic to humans, pets, fish and birds. It affects the digestive system of caterpillars when they eat the treated plant. Although it will also kill caterpillars of butterflies, they rarely feed on your vegetable garden plants. To be safe, don’t spray ornamental flowers that normally attract butterflies. Another reason I consider Bt a really good product is that you can use it as a preventative. It is a “non-contact” insect killer, which means the insects don’t have to be present and you don’t have to spray the actual bug. Bt can be used on products sold as organic.

ROTENONE

Although this insecticide is made from natural ingredients, is biodegradable, but it is not non-toxic. It is a contact insecticide (you have to actually spray the insect to kill it) and is not allowed to be used on produce to be sold as organic.

PYRETHRUM

This too is a synthetic insecticide even though it is made from Chrysanthemums.  It is highly toxic to fish and honey bees. It is a contact insecticide, and considered to have a low toxicity to humans. 

SAFER INSECTICIDAL SOAP

This product is made from natural oils and animal fats and is effective against aphids, scale and other soft bodied insects. It is considered non-toxic to humans and approved for use on organic produce. The downside is if you apply it in really hot weather in a sunny location you could damage your plants. 

Critter proofing your garden

My critter proof fence.

There is nothing worse than spending a lot of time and energy into preparing your garden soil, planting seeds and seedlings, and nurturing everything so you will have a good harvest only to have ground squirrels wreck havoc.

Birds are easier to deal with, since bird netting will keep most of them at bay. Fencing keeps out most animals like skunks and rabbits, especially if you bury the fence 8 to 12 inches so they can’t dig under. But ground squirrels, as cute as they are, are far more industrious and determined that most other problem critters.

Poisoning wildlife serves no real purpose other than upsetting the balance of nature. If you rely on poison you risk poisoning predators such as hawks, owls, coyotes and bobcats as well as the squirrels, and will spend a fortune. Squirrels are very prolific because they are darned low on the food chain.

There are also many repellents on the market touted to keep animals away from your plants. Some gardeners swear by pepper spray, Lifebuoy soap, certain aromatic plants, and mothballs, to name a few. However, my experience has been that nothing works other than a physical barrier. I’ve seen rabbits eat plants coated with cayenne pepper, so the fact is, you can’t rely on these products.

If you are just starting a garden and know ground squirrels live in your area, build a defense system early since once they figure out you have goodies planted, they try harder to get in. It does not matter how tiny the openings are in your fence, ground squirrels are not only adept at digging under fences, they also climb over fences. A 4 foot tall fence is nothing to these acrobats.

A non-climbable fence is a more expensive option than any wire fence, including chain link. What is considered non-climbable? Think something slick, such as corrugated metal or sheet metal. Yes, it will look ugly. But yes, it will work. You will need sturdy posts set in concrete, however, so it does not blow over in high winds.

Another option is to cut metal and attach to your existing fence, provided the openings on your metal fencing are no larger than ½ inch squares. The non-climbable portion should be placed at the top of the fence since they most likely will not be able to leap over the entire 4 feet.

Your fencing not only needs burying, but it should be in a L shape so they cannot dig under. An alternative is to lay 2 foot tall hardware cloth on the ground all the way around your fence, securing with U-pins or rocks.

Check your fencing regularly, since they are looking for weak spots every single day.

Sound like a lot of work? Yes it is. But having home-grown produce is worth every minute of it.