Consider Adding a Pomegranate to Your Home Orchard

The bright flowers and zingy taste of the pomegranate make it an ideal fruit tree for desert gardens.

Introduced into California by Spanish missionaries over two hundred years ago, pomegranate has long been a favorite in Arizona for its hardiness, color and fruit.  Pomegranates work well in desert landscapes because they are not finicky when it comes to soils and climate.

Native of the Middle East, from Iran to the Himalayan Mountains, pomegranates  thrive in  semi-arid, mild-temperate to subtropical climates throughout the world.  They are naturally adapted to regions with cool winters and hot summers.  Pomegranates will live for many years. There are specimens in Europe that are known to be over two hundred years of age. 

High humidity seems to adversely affect fruit formation.  Because of this, our arid, usually low humidity climate is perfect for the pomegranate.  The tree can be severely injured by temperatures below 12° F.

Properly cared for, pomegranate trees can reach heights of fifteen to twenty feet and as many feet wide, but most trees in the desert, for one reason or another, rarely exceed ten feet in height and width.  Dwarf varieties are available to fit smaller areas.

The pomegranate is usually deciduous, but the leaves will remain on the tree year round in warmer areas.  The trunk is covered by a red-brown bark changing to gray as the tree gets older.  You can also tell a pomegranate tree by looking at the leaves.  The glossy, leathery leaves are narrow and shaped like a lance tip.  There is a strong tendency for the plant to send out sucker shoots from the base of the plant.  These should always be kept pruned off.

Attractive scarlet, white, or multi-colored flowers lead to nearly round, two and one-half to five inch-wide fruit.  The pomegranate is self fruitful, meaning that it does not need another tree for pollination, and the flowers will accept pollen from themselves or from other flowers brought to them by insects. Cross-pollination increases the fruit set.  Wind does not play an important role in pomegranate pollination.

The fruit is surrounded by a tough, leathery skin or rind which is typically yellow inside and light or deep pink or rich red outside. The interior of the fruit is separated by white, spongy, bitter tissue into compartments packed with sacs filled with sweetly acid, juicy, red, pink or whitish pulp. In each sac there is one angular seed. High summer temperatures are essential during the fruiting period to get the best flavor.

The fruit of the ‘Wonderful’ variety, the variety most often planted in Arizona, matures and is ready for harvest in the fall, usually in November, although some other varieties may mature sooner.  The fruits are ripe when they have developed a distinctive color and make a metallic sound when tapped.  If you are in doubt of the ripeness of the fruit, pick one and test it before harvesting the rest of the fruit from the tree.

Once off the tree, the pomegranate can be stored at a temperature of 32°to 41°F.  Some have been able to keep the fruit in storage for up to seven months within this temperature range and at 80 to 85% relative humidity without shrinking or spoiling. The fruits improve in storage, becoming juicier and more flavorful so don’t be in a hurry to use them up. Be sure and save some for later.

The fruit can be eaten right off the tree by deeply scoring the shell several times vertically and then breaking it apart. The clusters of juice sacs are then lifted out from the rind and eaten. The sacs also make an attractive garnish when sprinkled on various dishes.

Pomegranate fruits are often used for juice.   After removing the sacs, run them through a basket press or by reaming the halved fruits on an ordinary orange juice squeezer. Another option  begins with warming the fruit slightly and rolling it between the hands to soften the interior.  A hole is then cut in the stem end and the fruit is placed on a glass to capture the juice as it runs out. Squeeze the fruit from time to time to get all the juice. The juice can be used as a fresh juice, to make jellies, sorbets or cold or hot sauces, and to flavor cakes, baked apples, and other specialties.  Pomegranate syrup is sold commercially as grenadine.  Pomegranate has been found to be relatively high in antioxidants, compounds that help protect the body from disease. 

The pomegranate does best in well-drained ordinary soil, but also thrives in saline soils or even rock strewn gravel.   In Arizona, the trees should be lightly fertilized with two to four ounces of ammonium sulfate or other nitrogen fertilizer once during each of the first two springs after planting. At maturity, the tree will do well with three applications of nitrogen fertilizer spread out over the growing season.  Fertilize it the same as you would a citrus tree.  The trees also respond to an annual mulch of rotted manure or compost.
                   
Once established, pomegranates will take considerable drought, but for good fruit production they must be irrigated regularly. Inconsistent irrigations will cause the fruit rind to split open and allow the entry of insects and diseases.  The optimal watering cycle for pomegranates is once a month in the cooler time of year. Once daytime temperatures are consistently above 85 degrees Fahrenheit, then the trees need to be irrigated every 10 to14 days. A good deep watering needs to wet the soil at a depth of two to three feet.

Trees planted during the hot months should be watered every day for the first two weeks to encourage root growth.  Afterwards, particularly after new leaf growth begins, the irrigation cycle can gradually be cut back to the normal rotation.

New plants should be pruned back when they are about two feet high. From this point you should allow four or five shoots to develop, but make sure that they are evenly distributed around the stem to keep the plant well balanced. These shoots will develop into scaffold branches that will bear the fruiting wood.  Scaffold branches should never be lower than one foot above the ground.  Any shoots or branches below this should be considered suckers and removed.

As new branches develop from off the main scaffold branches, make sure to shorten them during January or February each year for the first three years to encourage the maximum number of new shoots on all sides, prevent straggly development, and achieve a strong well framed plant. After the third year, only suckers and dead branches are removed. Since the fruits are borne only at the tips of new growth these extra branches will increase the fruit yield.

The pomegranate can be raised from seed but the plant that results may not have the same characteristics of its parent. For that reason, most new plants are made from cuttings.  Pomegranate cuttings root easily and plants from them bear fruit after about three years.

To take cuttings, cut sections of mature, one-year old wood twelve to twenty inches long and remove all of the leaves.  Treat the bottom end of the cuttings with rooting hormone and insert about two-thirds their length into the soil or into some other warm rooting medium. Plants can also be air-layered but grafting is seldom successful.  Keep the medium well watered and warm and soon roots will form.  These cuttings can then be transplanted into place.

When transplanting a pomegranate tree, choose a location with full sun with soil that drains well. The optimal times to transplant trees are in March or October.

Pomegranates are relatively free of most pests and diseases. Minor problems are leaf and fruit spot and foliar damage by white flies, thrips, mealybugs and scale insects, but the roots are seldom bothered by gophers.

Pomegranates can be planted close together for windbreaks, hedges and screens or planted by itself to make a highly decorative accent plant in the landscape.  Pomegranates should be placed in the sunniest, warmest part of the yard or orchard for the best fruit, although they will grow and flower in part shade.

The unique taste of the pomegranate fruit, along with its hardiness and attractive flowers, make this plant a good choice for any desert landscape.
                               
If you have questions, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204. 

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85122
Voice:    (520) 836-5221, 227
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Home Landscapes: Are They Really Important?

A garden or landscape costs time and money to install.  They can be a hassle to properly maintain.  Do we really need one? Should we just let the yard go, save the water, and avoid the time and effort required to keep it in shape?

More and more people are asking these questions of themselves as they weigh the costs of installing and maintaining home landscapes.  Water, fertilizers, and other inputs can be quite expensive and the work involved in maintaining an attractive, functional landscape can take up time and energy that could well be spent in leisure or other pursuits.  In times of economic downturn, these challenges can push the desire for a home landscape way down the list of things to do each day.  Unfortunately, in making the decision to ignore or neglect the landscape, they may actually be charging themselves other hidden costs.

Property values are one of these hidden costs.  When a home is sold, not only is the condition of house evaluated, but also the outdoor living spaces associated with the home.  The presence of trees and shrubs, and their overall health, could be key to placing a “sold” sign on the property.  The total value of the property, the amount that the home is sold for, often improves with an attractive landscape.

Another hidden cost can be found in the monthly power bill.  The desert Southwest receives more sunshine than any other part of the United States.  Pinal County receives more than 80 percent of possible sunshine each year.  While the winter sun provides enough warmth to make outdoor activities pleasant and helps heat the interior of buildings, the brilliant summer sunshine quickly brings indoor temperatures to intolerable levels.  When that happens, we turn on the cooler.  Cooling buildings in the desert is always an expensive process.

Interior temperatures result not only from direct solar gain to the building itself, but also from the accumulation of external heat in the surrounding outdoor areas.  The warmer the ambient environment surrounding a building, the warmer will be the interior temperature.  Heat radiated from outdoor hard surfaces, such as concrete, roofing, paved streets, and patio surfaces are part of the problem.  External temperatures are only made worse when unshaded soil is covered with stone mulch or cobblestone.  Even bare soil can present a problem.

Heat gain around our homes can be counteracted by installing and correctly maintaining good outdoor landscapes.  Plants cool by reflecting the sun’s rays away from buildings and shading outdoor living areas.  While unshaded walls absorb heat from the sun’s rays and transmit the heat to the interior of the building, landscape plants can intercept the sunlight and put it to good use.  In this way plants can help keep our homes and outdoor living spaces cool.  Wise placement of shade trees and vines can result in significant reductions in the high cost of cooling homes and commercial buildings. 

Consider these facts.  A dense shade canopy will screen out at least 80 percent of the solar radiation that falls on a human being, outdoor living area, or buildings in our area.  A wall in full sun transmits three times the heat of a shaded wall while an unshaded roof adds twice the heat of a shaded one to the interior of the structure.  Shading can reduce maximum high temperatures inside a typical house by 20 percent.  A quality landscape will be designed and maintained to provide maximum shading.

Another hidden cost is air quality.  As more and more people have found the wonderful qualities associated with living in Pinal County, air quality in many areas has taken a nose dive.  The pending action by the federal Environmental Protection Agency to address air quality problems in western and southern Pinal County is a good example of this problem.  As we evaluate the overall air quality problems, high on the list of particulate matter found in our air are particles of dust blown into the air by our occasionally nasty winds and traffic on bare soil. 

Dust in our air does indeed come from many sources, but homes without landscaping, particularly those with bare exposed soils, can have a staggering effect on air quality, at least in the micro environment.  Bare soils are particularly bad when they carry traffic, such as vehicles driving on bare soil.  Properly designed and maintained landscapes can minimize the loss of loose soil from the surface of the ground and help control dust around our homes.

Finally, homes that are not maintained and/or have landscapes that are either nonexistent or ignored for can indicate a lack of interest in our living environment.  Where lack of interest prevails, crime seems to follow.  So, indirectly, well maintained homes and landscapes can help reduce crime in an area.  This, in part, occurs because a sense of pride and ownership in our homes, even in rentals, tends to make us less tolerant of crime.  The increased neighborhood good will and community pride engendered by nice looking homes indoors and out increases a sense of belonging that often times results in a corresponding drop in crime statistics in an area.

No doubt we will find other “hidden costs” associated with abandoned or non-existent landscaping as we begin to search for them.  The choice is ours, however, whether or not we will allow those costs to accrue against us and our property.  Can’t we take a few minutes and assess the condition of our landscapes?  If there are areas where work is needed, let’s invest some time and money to improve the living conditions for us and our neighbors.

In summary then, we ask ourselves the question: “Is it possible to have a low cost, attractive landscape without taking a lot of time, money, and effort?”  Yes, there indeed there are options.  Dust control and a finished look can be achieved simply by laying down a simple crushed rock mulch on the surface of the soil.  Some people have chosen this route and have found that it suits their needs.  That is option one.

Adding shade and esthetics will require the presence of plants, generally trees, shrubs, and other plants.  Since water is always an issue in desert areas, and especially during drought conditions, we ought to select these plants from desert-adapted low water use plants.  That is option two. 
If you choose this option, please make sure that you give your plants good care and frequent irrigations to keep them healthy and productive.

In today’s environment, and for the good of the community, urban landscapes do matter.  With some input and initial labor, a functional landscape can be created and enjoyed not only by ourselves, but by the community at large.

If you have questions, or need more information, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture, Pinal County
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85122
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Growing Plants in a Desert Environment

It is a common lament made by those who are trying to grow plants in the desert for the very first time.

“Where I lived before, I could just throw out the seeds and everything would grow, but here, in the desert, the plants die, no matter what I do!” 

I know many people are frustrated in their attempts to grow healthy, vigorous plants, because I hear from them on a regular basis.  You may be one of them.

You plant, water, fertilize, and kindly talk to your plants even, but they do not seem to respond, no matter what you do.  Unfortunately, it is a true but sad state of affairs. Newcomers to desert gardening, and many old-timers, often find frustration before they find success.

I want to tell you, though, there is hope! Once you become accustomed to the rules governing desert gardening, there is no reason why you cannot join the ranks of those who find growing plants in Southern Arizona an extremely rewarding experience. 

The desert is an ideal place to raise fruits, vegetables and ornamental plants.  Successful desert gardeners enjoy lush, thriving landscapes and beautiful flower beds.  Others enjoy producing much of their own food in successful, healthy gardens.  There are three reasons why gardening in the desert can be a satisfying experience.

First, the environmental factors that make Southern Arizona a desert are the same factors that allow a wide variety of plants to be grown in our area.  Fruits from apples to lemons and ornamentals from pines to palms can be successfully cultivated.  The almost unlimited possibilities have produced landscapes of great variety and interest.

Second, the exact same environmental conditions also allow a year-long growing season.  With the correct cultural practices, fresh vegetables can be harvested all year long; beautiful, fresh cut flowers can grace an indoor table every month of the year and turf areas can be green and lush twelve months out of the year.  Many area gardeners find the unlimited possibilities both challenging and satisfying. 

Finally, the cultural practices necessary to successfully grow garden and landscape plants have been worked out and published for all to know.  By learning how to deal with the environmental conditions and by carefully adhering to correct gardening principles, most people should have little trouble enjoying the fruits of their labors.

Assuming that you have bought into believing that success is possible, we are ready to address some of the more important factors that sometimes get in the way of healthy gardens and landscapes.  These factors generally revolve around climate and soil.

Southern Arizona’s climate is determined by its latitude, elevation and geography.  The latitude, or the distance from the earth’s poles, determines the amount of solar radiation, or sunlight, that a location receives.  Solar radiation is critical because it drives photosynthesis, the life process that is so necessary for plant growth.  The more solar radiation, the more vigorous the growth of plants. Since we are closer to the equator than many parts of the country and because of our generally bright, cloudless days, we receive more solar radiation.

Elevation has a great effect upon our climate.  Take temperature, for example.  Generally, the higher the elevation in Arizona, the lower the average temperatures, both during the day and night.  At our relatively low elevations, warm temperatures create a year round growing season. 

Every plant has an upper limit and a lower temperature limit.  In our desert, both extremes can affect plant health and growth.  It is just as important to protect our plants from the high temperatures of summer by watering correctly as it is to protect tender young plants from frosts in the winter.  Plants cool themselves by releasing evaporated water through tiny pores on the bottom of their leaves and the release has the same effect as a swamp cooler in our homes.  If plants run short of water, they die.

Nighttime temperatures also influence the growth of plants.  Some plants, such as our winter vegetables, do best when night temperatures are around 50 degrees F., while others do best when the temperatures are 60 degrees F. or higher.  Bermudagrass, for example, usually does not start to grow well in the spring until night temperatures reach 60 degrees F.

Rainfall, another climatic factor, is almost always insufficient to grow plants.  Many make this mistake, even with supposedly desert hardy low water use plants.  To maintain good plant health, rainfall almost always must be supplemented with irrigation, especially when plants are young and just getting started.  Proper irrigation is essential for good plant health.

Humidity affects the health of plants in may ways.  On the positive side, low humidity stifles the growth and development of many plant diseases.  For this reason, plants growing in the desert are often disease free as compared with similar plants growing in a more humid environment.  On the down side, the low humidity of June and July means that plants must be irrigated more frequently and with greater amounts during those months in order to keep them healthy. 

Wind can definitely be a factor.  The strong, dry winds of the desert can quickly dry out tender plants and send them into a tailspin of leaf injury and dessication.  In addition, most people have seen the flotsam and jetsam of broken branches and tipped over trees after our summer storms. Proper irrigation, correct staking and good pruning techniques will take care of most wind issues.

Geography, the features of the land such as mountains and valleys, affects microclimates as well as soil.  Microclimates are pockets and places where climatic conditions vary somewhat from the norms of the desert climate.  Planting strawberries on the north side of a home or fence will often allow them to grow through the summer where a south facing exposure would probably kill them off during the warm months. 

Our geography also determines many of the soil factors that impact plant growth.  The broad, flat valley floors where most people live were developed though many years of erosion that brought soil particles down from the surrounding mountains to fill the low lying basins.  Because of this, there is a wide variety of soil types that affect plants differently and these must be understood to successfully manage the growth and development of plants.  Alkali, salinity, low nitrogen fertility, pH, caliche and compaction all find their roots in the dry climate of the desert.

While there is not time, nor space, to talk about all of the factors in detail, it is important to be aware of them and to take the time to know how to deal with them.  Let’s continue to talk about them in the future.
                   
Success is possible in growing healthy and productive landscape and garden plants.  The most important rule of desert gardening and landscaping is to learn how to work with the environment instead of against it.

If you have questions, or you would like more information on any of these topics, visit with one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture, Pinal County
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Growing Cacti in Raised Beds

Growing Cacti in Raised Beds

Rick Gibson

Cooperative Extension Agent, Agriculture

Pinal County, Arizona

If you would like to enjoy the colors and textures brought by the many species of cacti but dread the spines, consider a raised bed garden for these prickly plants.

A cactus garden can be a wonderful way to enjoy the colors and textures of cacti in the home landscape, but working around the plants, especially prickly pear and cholla, can be a painful experience.  A raised bed cactus garden is a good way to keep hands, arms and feet away from the spines and still experience the many beautiful species of cacti that will grow in this area. 

The familiar saguaro, barrel, hedgehog, Mammillaria, prickly pear and cholla cacti are all native to the Sonoran Desert and are well adapted for landscape use in our area.  Their presence in a landscape can give that authentic touch of native dignity that seems to legitimize and complement Arizona desert landscapes.

In addition to the native species, there are many non-native species that also do well in the desert environment.  Compass barrel cactus, Ferocactus cylindraceus, and the“old man cactus”, Cephalocerus senilis, are examples of species from other areas.  A landscape decorated with a mix of these exotic cacti and species from our own Sonoran Desert can be quite interesting and unique.

Because of the way that they are built, and the way that they carry out their life processes, cacti are well adapted to desert living and make good low water use plants.  The thick, wax-coated stems of cacti, for example, are quite resistant to moisture evaporation.  This ability to protect themselves from significant water loss through their tissues gives them considerable drought tolerance.

Cacti are leafless, but almost all of them have modified stems called spines.  These spines can be straight and needle sharp, such as in the hedgehogs, or curved and broadly pointed like the barrel.  These modified stems give a measure of protection from the feeding of animals that might be looking for a source of water.  They can also cause a painful experience if one gets too close.

The prickly pear and cholla species have the straight defensive spines, but these particular cacti are especially painful because they have a second type of spine.  These tiny spines, called glochids, are hair-like whiskers with barbed structures on their surfaces.  Almost invisible to the eye, they can be quite painful and troublesome.  Many who have experienced these tiny spines have come to appreciate the value of sticky tape and tweezers as they have struggled to remove them from their skin.

It is the presence of spines, especially these glochids, that lead many to shy away from planting cacti in the landscape.  A misstep off the path in a cactus garden can lead to a painful encounter with cacti.  Dragging hoses to water other landscape plants almost always results in spines becoming attached to the hose.  Invariably, these spines will be transferred from the hose to the hands, arms, and legs of whoever might later be coiling the hose for storage. 

One way to help prevent these types of encounters and to help keep the proper distance between people and plants is to place the cacti in raised beds.  The framework that creates the raised bed  will automatically set the limits between space set aside for people and space that is set aside for cacti.  The raised bed sends a strong message to all: venture beyond at your own risk. 

Besides physically limiting the possibility of people and pets to move into the garden space, the raised bed structure itself creates a barrier that will prevent a hose from being dragged into the cacti and serves as a boundary limit that will protect wheel barrows, electrical cords and other garden tools from coming in contact with the spines.  It provides an extra layer of safety.

The raised bed garden also makes an ideal showcase for viewing the cacti.  By locating the cacti closer to eye level, it places them in a position where their good points can be more easily seen. 

To create a raised bed for cacti, consider using railroad ties placed side by side and end down to create a strong barrier.  The ties should be buried about eighteen inches deep into the soil to prevent the weight of the soil inside the bed from pushing out the framework.  The height of the bed can vary but probably should not be taller than twenty-four inches or less than twelve.  The framework for the bed can be built square for a formal look, or with softened corners for a more natural feel. 

Other materials can be used for a raised bed.  Decorative or standard concrete blocks, lumber or even old, worn out tires can be painted and stacked in various arrangements to provide an interesting, but effective arrangement.

Soil used inside the garden should drain well.  For this reason, it is recommended that soils should contain large amounts of sand.  Place the soil in mounds and plant the cacti at the peak of the mound so that water will drain away from the base of the plant.  Water accumulating around these plants can cause the base to rot and eventually lead to the death of the plant.

Weeds can cause a huge problem for those working in cactus gardens.  Weeds growing in close proximity to spines will be difficult to remove by hand.  Locate the garden well away from Bermuda grass lawns to prevent the invasion of this tough weed, and make sure the soil inside the garden is free of nutsedge tubers and other perennial weeds. 

Most weeds in a cactus garden can be prevented by placing a one to two inch layer of rock mulch around the plant.  Larger rock, such as 1.5 inch leach rock, makes the best mulch, but other sizes and colors will also work.  The use of plastic on the surface of the soil under the rock mulch is not recommended.  It prevents surface water from sinking into the root zone and with each passing dust storm supports the accumulation of an artificial zone of soil on top of the plastic in which weed seeds can germinate.

With a little time, energy and know how, a raised bed garden will define the safe boundary between people and cacti and, at the same time, show off the various species in an attractive way.

If you have questions, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Container Gardening Offers Many Benefits

Container Gardening Offers Many Benefits

Rick Gibson
 Cooperative Extension Agent, Agriculture

Pinal County, Arizona

As residential lots get smaller and smaller, there seems to be a growing interest in using containers to grow plants outdoors.
 
I can see why.  Trees, shrubs, flowers, vegetables and vining plants all do well in containers.  Containers can be moved around, within reason, to accommodate changing needs and to create different landscape moods.  Container gardening creates opportunities where people of all ages can mix and mingle in wholesome activities.  Children, as well as adults, often find great satisfaction in mixing soils, potting plants and watching new life begin.

Container gardening is similar in many ways to regular gardening in native soils, but it also is very  different.  It is these differences that offers challenges, and sometimes failures, to those who attempt to grow plants in containers.

Obvious benefits of gardening in containers are many.  One of the greatest is the amount of gardening  space required.  Because container-grown plants are often kept smaller in size by  reduced root volume,  less space need be dedicated to plants.  Container gardening lends itself well to those living in apartments and to those with small outdoor living space.  However, the joy of gardening in containers can be enjoyed by all.

Another great benefit of container gardening is that it avoids all of the problems and pitfalls of gardening in our alkaline desert soils.  Because container gardening allows us the opportunity to select our own potting mixture, we can control the nature and chemistry of the root environment and avoid the common problems of salt, caliche, and low fertility found in our native soils.

Container plants also provide great flexibility in decorating for special events and for special needs.  Many have discovered the potential provided by container plants for enhancing the appearance of outdoor property for weddings, outdoor parties and other activities.  Many also find it easy to add attractive color and variety to the property when a home is up for sale.  

A final benefit of container-grown plants is the potential protection that containers can provide from gophers, ground squirrels and rabbits that sometimes ravage soil-grown plants in outlying areas near non-developed areas.

Just about any plant, even trees with the correct-sized pot, can be grown in containers.  Plants that grow rapidly actually seem to do best.  Tomatoes, eggplant, peppers, melons, and leafy vegetables are some of the edible plants that can flourish in containers.

With the exception of metal, any container will do.   Metal containers get too hot during the summer and damage tender roots and lower shoots.   Make sure that the container is deep enough to hold sufficient potting soil to support plant growth.  It really doesn’t matter how attractive the container is.  Less attractive containers can be hidden behind more attractive pots as plants are grouped together.

Use a standard potting soil.  Regular desert soil, dug right out of the garden, will carry weed seeds and disease pathogens and these problems will be magnified in pots.  Most potting soils purchased commercially have either been well composted to eliminate weed seeds and disease organisms or have been sterilized.  A good potting mix would combine equal amounts of compost, peat moss or vermiculite and pumice.  While expensive, pumice is useful because it  holds water well and helps provide drainage and aeration. It also can help prevent compaction as the mix dries.   Regular sand can take the place of pumice, but make sure that it is well washed before use. 

Every container should have good drainage out the bottom.  Drainage is essential because of the root’s need for air.  A good mix will be about 50% solid material and 50% water and air.  The spaces between the solid matter is where the water and air are found.  Obviously, when we water,  most of the air in the mix is driven out.  As the plant uses the water in the soil or as the water evaporates from the surface of the mix, air will follow down through the spaces.  Ideally, there will be both water and air sufficient to maintain the good health of plants.  Match the size of the pot with the size of the plant.

Drainage holes in the container can be covered with a shard of pottery, a stone, or a piece of  plastic or metal screening to keep the potting soil from dribbling out the bottom.

When selecting plants for container culture, select plants for different colors, types and textures.  Plant a trailing vine to an upright stalk.  Mix in herbs and perhaps vegetables with grasses and ground covers.  Plant annuals together with perennials for an interesting change .  Build a trellis for vining plants like beans, cats claw or sweet peas.  Experiment with different arrangements and plant types to see what works best for your situation.

Potted plants dry out more quickly than those planted in the ground.  Proper timing of irrigations is critical.  It helps to group plants of similar need together and then hook up a drip system on a timer to deliver the amount of water at the frequency necessary to maintain good plant health.  Many problems associated with container plants can be solved by careful management of water. 

Plants in containers also need adequate fertilization.  Because the root system is confined to soil within the pot, available nutrients are more frequently mined from the relatively small area. With the exception of cacti and succulents, such as the agaves, add a diluted water soluble fertilizer with each irrigation.  The constant but light application will provide the plant with the necessary nutritional needs required for good growth in the containers.

Make sure that the fertilizer applied contains all three of the major nutrients commonly provided by commercial fertilizers.  These are nitrogen, phosphorus and potassium.  Artificial container soils will not provide large amounts of nutrient and the use of a complete fertilizer will be necessary.  The label of the product will tell exactly what nutrients are provided.

When beginning to garden in containers for the first time, it is advisable to start small and work up.  There is a knack to growing good plants in containers.  To avoid major failures, it is a good idea to work with one or two pots until you are confident that you maintain the plants in good condition.

Container gardening can be an exciting experience for all who love plants.  Following a few basic rules will help bring success.

For more information on how to garden in containers, ask for a copy of the Cooperative Extension leaflet, “Growing Vegetables in Containers”.  If you have questions, you can reach a Master Gardener at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Ironwood Trees in the Landscape

Ironwood Trees in the Landscape

Rick Gibson

Cooperative Extension Agent, Agriculture

Pinal County, Arizona

Let me give you a common scenario that I see way too often. 

A homeowner wants to lower his or her monthly water bill and decides to do it by cutting back on outdoor landscaping.  In a moment of decision, the outdoor irrigation system is shut off and, just like that, the water bill begins to drop.  Unfortunately, a few weeks or months later, the plants begin to turn yellow and die. 

As the plants begin to shed leaves, the amount of shade provided by the plants begins to diminish and sunlight begins to break through onto graveled yard surfaces and structural walls.  The increased sunlight raises the temperature of these hard surfaces.  With increasing heat radiating back into the environment, the home owner begins to notice an increase in the power bill as the air conditioning unit works overtime to keep the home cool.  Seeing the electricity bill, the homeowner recognizes the problem, taps the head and says, “What was I thinking!”

Trade offs between water and power bills are not uncommon as we struggle to balance between our need to conserve precious resources and the rigors of every day life.  However, we do not have to settle for a bare, unattractive yard just to save money.  By using plants that get by with a minimum of water, we can lower water and electricity bills and still have pleasing outdoor living areas.

Because of their size, trees use a large percentage of the water in a landscape so one area where we can cut back on water is to choose  water stingy trees for landscape use.  One of the stingiest of low water use trees is the local desert ironwood, Olneya tesota.  It is a hardy, well-adapted, handsome plant that works exceptionally well in a low water use landscape.  It takes full sun, has many landscape uses, and gets by on very little water.

A member of the legume family, it has the typical compound leaves of the mesquite and palo verde family.  A compound leaf is one that has a central stalk, called a rachis, and along the stalk are little leaflets that together form the leaf.  These leaflets are a striking gray-green color and are typically larger than the mesquite leaflets.  The dense canopy gives the ironwood top billing in my book as a screening and shade tree in the landscape.  Be careful, though.  At the base of each leaf, not leaflet, there are two sharp-pointed spines that can easily prick a finger.

The tree flowers in the late spring in a showy display of pinkish-lavender sweet pea-shaped flowers, each about one-half inch long.  I think the tree is absolutely gorgeous in full bloom.  Just before flowering, the tree will give you heart failure as it sheds most of its leaflets.  You would think that the tree is dying just to look at it, but not to worry, it is a normal part of the growth pattern for the tree.

The flowers turn into dark brown, fuzzy, two inch-long pods that split open at maturity and let the seeds fall to the ground.  The seeds are highly prized by small mammals in the desert for food.  They have also in times past been collected and used for food by humans.

Ironwood trees, depending upon soil and water conditions, will grow to between fifteen and thirty feet tall and the same dimensions wide, so in landscape situations it is important to give them enough room to grow.  The spines, like many desert trees, can make them formidable so do not plant them next to walkways or other high traffic areas. 

The wood in the center of the branch or trunk, as aptly described by its common name, is extremely hard.  The wood has been used in the past for arrow heads and other tools.  The cured wood is also highly prized as a cooking fuel.  It burns hot and Dutch oven enthusiasts appreciate the hot, long lasting coals.  The wood is also used by artisans for carving and other uses.  The Seri Indians of Mexico have developed quite an art form for their carvings.  The wood is heavy, weighing up to 66 pounds per cubic foot.  I know of an ironwood dining room table, over eighty years old, that is so heavy that it took a crew of men to move it into place. It has never been moved since!

As a landscape tree, the ironwood has many uses.  Because it can be either a single or multi-trunk plant, it can be developed to fit into that special spot made difficult because of angles or corners. It is possible to plant a whole forest of ironwood trees and no two would be the same.  It may take some careful pruning, especially early on, to develop and maintain a desired form, but it will be worth the effort later on.  Don’t worry if the branches tend to grow up while the tree is young, they will begin to spread as the tree matures.

In the wild, ironwood trees grow near washes or dry stream beds where deep water is usually available.  This means that it will require some water to do well, a deep irrigation once or twice a year at maturity will probably be enough, but the naturally slow growing tree will hasten its growth with more frequent irrigations, especially during the summer.

Beside its trunk shape, the ironwood also has other characteristics that make it valuable as a landscape plant.  Its dense canopy of leaves makes it ideal for screening, background, and shade uses.  Its flowers provide spring color.  It is excellent as a thorny barrier to reduce traffic flows or for security, and its striking appearance makes it valuable as a specimen plant.

The tree requires full to reflected sunlight so it should be placed in a location where it will not be shaded by other plants.  It performs well under harsh growing conditions but it is frost and freeze sensitive so it should be planted in regions where winters are warm enough for citrus.  Since it prefers a soil with good drainage, it is not a good choice when you are dealing with a clay or caliche soil.  

If you intend to plant your ironwood tree from seed, it will be important to scarify the seed either by running them through a rock tumbler filled with sand or by using a file to cut through the hard seed coat.  Insects usually are not a problem but mistletoe infestations can distort and weaken branches.  Mistletoe seeds are usually spread from tree to tree on the feet of birds so most infestations occur most frequently on larger trees that are apparently more attractive to the animals.  Watch for signs of mistletoe plants and cut them out early.

The ironwood tree offers many benefits as a low water use landscape tree and can provide color, texture, shade, and screening to any landscape.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, AZ 85222
(520) 836-5221 ext. 227
(520) 836-1750 - Fax
gibsonrd@ag.arizona.edu

Spring Wildflowers

Rick Gibson

University of Arizona Cooperative Extension

Pinal County

Winter rains this year created a good display of wildflowers.  I hope you were able to get out and enjoy them while they lasted.

A spectacular year for wildflowers means that the desert is awash in color. The flanks of desert mountains, such as Picacho Peak, are colored gold, blue and yellow.  The desert floors, not just the sides of highways, are colonized by flows of color.  In poor years, there are few if any blossoms to enjoy.  While we did not get to see the truly spectacular in 2013 it was still a pretty good year.

Pinal County is a great place to see desert wildflowers. The best displays are usually found on the slopes of rocky hillsides and along paved roads.  Rocks, pebbles and gravel help mulch the desert soils and slow evaporation.  Paved roads shed water to the sides and irrigate young seedlings. The extra moisture works to the advantage of the wildflowers which need regular moisture to carry them through to maturity.  Highway 79 from Florence Junction to Oracle Junction is often a great place to see wildflowers.  You sometimes can also find a decent display along US 60 from Apache Junction to Superior, and along other paved roads in the county.  Boyce Thompson Arboretum in Superior and Picacho Peak State Park between Eloy and Redrock are great places to see the flowers up close and personal.

How do you know if it is going to be a good wildflower year?  Ample and timely winter rains that begin in November and come at two week intervals during the winters months almost always bring about a lavish display of desert wildflowers in the spring.  Here are a few tips to prepare for finding and enjoying wildflowers.

First, make the experience more enjoyable by learning the names and a little basic information about the flowers you see.  Unless you are really into botany, it will be hard to know them all, but start with the more common flowers and work from there.  Take some kind of a reference book with you to help you identify and learn about that particular flower.  A good field guide, preferably with color pictures, will prove to be an invaluable friend.   Botanical gardens and arboretums often have educational displays that describe these plants.  They might even have sections on display where nameplates identify wildflower plants.  Another choice would be to join in on a tag-along tour guided by a native plant expert.  I like to learn as much about the plant as I can.

Second, don’t just look at color alone.  Be aware also of the various arrays of textures, the interaction of the flowers with the natural environment and how the various colors intermingle with one another to present a full, broad picture.  Look also at the structure of the flower; how the petals are arranged and if they have more than one color in the bloom.  Artists have long known that to truly replicate the scene on canvas, they have to pay attention to the way light filters through the plant parts, particularly the petals.  Wildflower blooms are often intricate mixtures of colors and textures that often go unnoticed when we focus on only one piece of the puzzle.

For added enjoyment, I recommend that you also pay attention to how the flower fits into its native environment.  Why did it attract your attention?.  What is it that made you look at it, and how did you feel when you did?  For example, a desert marigold along the side of a road attracts the eye, gives a sense of color and fits into a larger plant community.  A single desert marigold growing next to a large granite boulder may give a totally different feel or view.  Your first thought may be one of isolation, or solitude and quiet.  A pocket notebook is a handy place to jot down your observations so that you can go back during the heat of the summer and remember a great Arizona experience.

Finally, learn a new flower each time you go out.  Over one hundred different species of wildflowers have been identified in our area alone and the search is always on for new and different varieties.  Many flower enthusiasts keep a record of the species that they see each year.  They consider this as part of the fun of searching for and identifying these beautiful plants.  They compare their lists from year to year to see what has changed and then share what they have found with friends and acquaintances.  This interchange of ideas from season to season not only makes for good conversation, it also helps to truly begin to understand the fragile, intricate web of life in the desert.

Of the many species that can be found locally, some become old friends because they are seen just about every year.  Others may be new acquaintances.  The more common varieties include the gold-colored California poppy, the deep blue lupine, the yellow desert marigold, the purple filaree and the orange globemallow.  We expect to see these flowers whenever there is even a hint of effective moisture.  However, it is fun to also look for the less common species like the rock purslane, evening primrose and scarlet pimpernel. 

Many people capture the beauty of the desert in their own yards by planting wildflowers in desert landscapes and then giving them extra water during dry winters to ensure that the flowers will germinate, grow and produce seed for the next year.  There are many yards that have spectacular displays even during the driest of years.

Most wildflowers can be planted from seed and are fairly easy to grow.  They do not need fertilizer or special care other than regular and frequent irrigations.  Seed of some of the more common varieties, such as the California poppy, can be purchased from nurseries, but it is too late this year to plant them.  Wildflower mixes are usually planted in November for a spring bloom. 

Some seed companies specialize in native plants.  Seed for individual species as well blends can be ordered through their catalogues.  Again, extra irrigation, beginning in the late fall and continuing through the flower season, will produce a bumper crop even in low rainfall years.

Wildflowers are fleeting, at best.  Soon the rains stop, the summer heat returns, the desert enters its summer dormant state and the displays are finished until the next time the winter rains come early and frequent.  No one can predict when that will be so be ready to enjoy them when you can. 

If you have questions, you can reach a Master Gardener at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu