Come Join The Master Gardener Program

For years the Master Gardener program has provided a wonderful opportunity for people to help others learn and grow gardens and friendships. Please take a few minutes to listen to some of our Pinal County Master Gardener volunteers talk about what the program means to them.

For information on how to join the Master Gardener program contact the Pinal County extension office at: 520-836-5221

For more details about the Master Gardener program in Arizona visit our webpage.

Pruning Deciduous Fruit Trees

With the leaves off of deciduous fruit trees, it is time to prune.

There are two main systems of pruning and each has its place.  The open center system is commonly used for peach, plum and nectarine trees.  The modified central leader system works best for apricots, apples and pears.  Both systems help keep the plant short so that cultural and harvest practices can be more easily carried out. 

The modified central leader system requires the removal of the main stalk or stem during the first year of growth.  The following year will result in the growth of several side branches from which three or four evenly spaced branches can be selected for fruit production.  As the tree grows, a new grouping of lateral branches can be selected every thirty to thirty-six inches along the central leader.  New side branches can be encouraged by cutting back the central leader just above the point where new branches are desired.  Once the form is established, it is simply a matter each year of keeping the tree thinned of small branches in undesirable locations.  Apples, pears, and apricots are commonly pruned to this method.

Apple and pear fruit are mostly borne on spurs supported by wood that is two years old or more.  Pruning should maintain as many of these spurs as possible.   All cuts should be made to divert growth towards the outside growing points.  With the pear’s upright growth habit, this is a relatively simple procedure.  Thinning new growth forces the tree to produce new fruiting spurs.

The apricot produces most of its fruit on short-lived spurs.  The goal is to remove branches with old spurs and keep the trees producing good replacement wood.  This procedure weeds out unproductive wood and allows light to penetrate to the center of the tree.  This in return forces new spur production.

The open center method results in a vase or bowl shaped appearance to the tree.  It  allows sunlight to more easily penetrate the interior portion of the tree and encourages the development of strong branches that will support a large crop of fruit.  Nectarines, peaches, plums, and sometimes apricots are pruned to this method.

Peach and nectarine fruit are borne on the previous year’s growth and new fruiting wood must be produced each year.  Heavy annual pruning is the rule for these trees.  Remove at least one-half of last year’s growth by cutting back the growth to an outside bud.  Recent growth will be found at the tips of branches, have a different color, and will be above the previous year’s terminal bud scar. Make sure that the limbs which are retained are forced outward.  If numerous laterals are produced from pruning, thin to one or two branches.  While the center of the tree should remain open, it is not advisable to strip the center of all bearing wood.  If all the wood is removed, there will be nothing to protect the tree from sunburn later on.

Plum fruit are borne on spurs two years old or older.  Spurs should not be removed except when potential fruit thinning is desired.  Thin out about one-third of the previous season’s growth by cutting undesirable branches back to their point of origin. 

Citrus cultivars do not need pruning to maintain fruit production like apples, peaches and plums.  The fruit are mainly borne at the tips of the tender branches and removal of these tips will result in reduced fruit production the following year.  However, dead branches that have been shaded out in the interior of the tree can be removed at any time.

Some people desire to shape citrus to a certain form and are not overly concerned with fruit production.  When shaping citrus for ornamental purposes, do not cut so deeply that sunlight will be able to penetrate the canopy and strike the bark of the trunk and limbs.  The wood is extremely sensitive to sunburn and could result in serious damage to the plant.  Again, shaping will reduce fruit production.


If you have questions, call one of our Master Gardeners at 820 E. Cottonwood Lane 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.

Aleppo Pine Blight

About this time of year we begin to see browning of Aleppo pine branch tips on some trees. I hope to reassure you that, in most cases, there is nothing to worry about.

Aleppo pines can start to look pretty ragged during the colder parts of the year with brown patches scattered throughout the tree canopy.  In most cases, this is a reversible condition that should get better as the weather warms in the spring.  The effect can often be minimized by making sure that the tree gets good care.

The Aleppo pine is a good choice for the low desert areas of Southern Arizona because it is well adapted to our harsh climate and alkaline soils.  It attracts few, if any insect pests and it has no major diseases to shorten its life.  It is a fast-growing tree and it provides good shade for our hot, summer days.  It has been, and continues to be, a landscape stalwart in this area.

It does, however, have one disconcerting tendency.  The needles close to the tips of some branches during the cool winter months can turn an unsightly brown.  Sometimes the needles stay flexible and turn green again as the weather warms.  Sometimes the needles will actually die, turn brittle and fall off; but the twigs and branches that support the needles usually stay green and will eventually regrow new needles.

The browning condition is referred to as Aleppo pine blight.  The disease is not caused by fungi, bacteria or insects.  It is a weather-induced shock to tender, actively growing needles at the tips of the branches.  Since not every branch of the tree is affected, the browning effect gives the tree a part-green, part brown appearance that can lead one not familiar with the condition to believe that the tree is dying.  In reality trees rarely, if ever, die of Aleppo pine blight.

With all of the recent publicity given to the bark beetle devastation in Northern Arizona pine forests, it is logical to assume that the browning of Aleppo pines is somehow related to these beetles.  You can ease your minds on that matter. 

First of all, the bark beetles of Northern Arizona do not like the desert climate.  It is too hot here for them.  Second, if the damage now seen in Aleppo pines were caused by bark beetles, the twigs and branches would not remain green to produce new needles in the spring.  Third, the damage would not be spotty on the tree.  Bark beetles cause a rapid decline and eventual death of the entire tree. 

While the specific cause of Aleppo pine blight is still unclear, there are a couple of theories that have been proposed.  One states that the effect develops when there is not enough time between warm and cold weather in the fall and winter to allow sufficient winter dormancy to develop.  Certainly, the variable weather that we have been experiencing in past years lends support to this theory.  One week, the fall temperatures can be in the eighties and nineties; the next in the low forties and even in the thirties.  This transition is hard on plants.

Another theory blames the browning of the needles on a previous stress for water and nutrients.  Most plants under stress often shut down part or all of the plant for a time until conditions for growth and development are better.  A good example of this is the ocotillo.  When warm, dry weather arrives, the ocotillo sheds its tender leaves and goes to sleep.  Once  the rains come again, the plant reawakens, puts on new leaves and begins a new growth cycle.  Aleppo pine blight may be an example of a similar response by the Aleppo pine.  The tree may simply not have enough strength to support the many needles on all of the branches of the tree, and the browning may be a move by the tree to cut back to what it can sustain.

Symptoms of Aleppo pine blight are noticeably striking.  Affected foliage suddenly dehydrates, turns whitish green, then brown, usually in the cool months of the year.  A few green needles or parts of an individual needle may survive in the midst of the blighted ones.  Some defoliation may occur and tree sap may sometimes seep from the blighted twigs.  In the more severe cases, some twig die-back may actually result.

The blight may be triggered in part by night-day temperature extremes and drying winds, since the symptoms usually show up on the sun-exposed, windward tops and sides of the trees.  Most affected branches survive this peculiar affliction and readily replace the brown needles in late spring and early summer as the trees begin their new growing season.

A good way to diagnose this particular problem is to bend the affected needles and twigs.  If the needles and twigs are brown beneath the bark and become brittle so that they snap easily, it may be that the tree is experiencing dehydration and death of some of its parts due to severe water stress and heat injury.  If the needles are still flexible, or only a few are brittle, the problem may simply be the Blight. 

While the symptoms of Aleppo pine blight may never be completely eradicated, there are a few steps that can be taken to ease the problem in most trees.  Make sure that the tree gets at least a monthly deep irrigation throughout the entire root zone of the tree and apply  a nitrogen fertilizer at least twice a year to support new growth.  

There is a slight chance that browning of needles and death of twigs may be related to a more serious disorder, such as root rot generally associated with too much water, but that condition is rare.  It is important, whenever there is a condition of which we are not sure, to always be vigilant and watch for signs that the problem is getting worse.  The Aleppo, however, is a pretty resilient plant and usually does not give its owners too much to worry about.

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

Pruning Trees along Public Streets

If your tree is growing next to a public walkway or street, you will want to keep it pruned for the safety and protection of others.

Trees growing along streets, sidewalks, and other public areas are governed by city, county, and state codes that are created and put into force to protect the general public.  Trees growing in or along public areas can cause safety issues if they are not correctly maintained.  Acting as good citizens, it is important that we do our part to keep our homes and communities safe for others.

While pruning for public safety is essential, it must be done correctly for no other reason than to maintain the long life and health of the plant.  Improper pruning opens up channels for disease and insect infestation and destroys the natural form of the plant.  Perennial plants store their extra food supplies created through the process of photosynthesis not only in the roots but also in the wood of the trunk and branches.  Heavy pruning removes large quantities of wood and energy needed by the plant.  Weakened trees become more susceptible to insects and diseases.  All of these can cause safety issues in their own right.

Normal pruning techniques require the removal of dead, damaged, or misplaced branches in that order.  In so doing, we try to keep a tree or shrub uniform in appearance on all sides of the plant to mimic what the plant would look like if it were growing wild.  We strive to maintain its natural form.   

I would be the first to agree that pruning for safety might require a stretch of these normal rules of pruning.   Growing alongside a street or sidewalk, a tree or shrub might need to be altered on one side to accommodate pedestrian or vehicular traffic.  Hiding a stop sign, the plant may need to be thinned to allow visibility.  Please, even in these situations, there is no call to hack away at the plant willy-nilly and throw out completely the proven rules of pruning. 

Good pruning helps ensure good health.  If we are going to go through the expense of purchasing, planting, and caring for the plant in the first place, why throw all of that good hard cash out the window by massacring the poor thing?  There are ways to do the job without seriously damaging the plants.

Pruning for safety usually means cutting back trees and shrubs that may obscure the vision of drivers, scrape or scratch vehicles as they pass, or force pedestrians out into a street or road.  In these cases, selective cuts must be made to improve visibility and remove the chance of injury or damage.  Let’s review a few basic rules of pruning and how they might apply to situations where public safety might be an issue.

The easiest and best way to prevent problems later in the plant’s life is to begin the training process early.  Making cuts to young plants when the branches are pencil size and smaller is less stressful than cuts made to larger branches.  Allowing the canopy to develop naturally by removing entire branches that are growing in the wrong way early on will maintain the number of leaves necessary to store energy for the plant and at the same time push the growth in directions that will be less offensive to the public traveling nearby.  Then, as the plant matures, it is a simple matter to make small, less invasive, corrective cuts.

When working on mature trees, don’t just hack at the plant.  The most common but least advised way to meet height limits for trees is to simply hack off the branches at the desired height.  This is not a good idea because the stump ends of the branches are susceptible to insects and diseases.

One of the quickest ways to infect a tree with heart rot or provide an entry way for insects is to leave a blunt end of a cut branch.  Blunt ends and stubs, any cut end of a branch upon which one could hang a hat, almost always die back. Dead or dying wood emits an odor that attracts wood decaying insects like flat-headed wood borers and others.  Attracted to dead or dying wood, they enter in for a free lunch and then set up housekeeping, sometimes even penetrating down into healthy wood.  How can we avoid this?  Don’t leave blunt ends and stubs.

The correct procedure for making cuts is to follow the offending branch back to its point of attachment and make the cut there.  Any cut of a branch pencil size or greater should be made in this manner.  If possible try to force the remaining growth upward and out by retaining branches that grow in the proper direction above the mandated height limitations.  Don’t worry about applying a pruning sealant to the cut.  In our dry climate research has shown that they are not needed.

As you make your cuts it is important to remember to preserve the branch collar.  The branch collar is a swelling of tissue at the base of the branch or limb that is full of  actively dividing cells.  By leaving the collar, a pruning wound will cover and seal over faster than if the collar is cut away. 

We often refer to cuts that remove both the collar and the branch as a “flush cut.”  Flush cuts, or cuts that are made flush with the older branch or trunk, are unhealthy, weaken the branch, and should be avoided at all costs.  Where a branch collar cannot be identified, we look for the branch bark ridge, a ridge of bark between the two branches and then from the base line of that ridge estimate out a 45 degree angle and make our cut.  A cut at a 45 degree angle to the bark ridge should avoid a flush cut and not leave a stub.

So, let’s say that we have a fully mature tree with branches clearly hanging down too far into a roadway.  What do we do?  The first step is to take a good look at the tree and make a plan.  Start by looking at the top of the tree and work down.  Most trees have a central leader, a main trunk from which side branches emerge.  It is important to protect the leader because it will be the point of upward growth for the tree.  Next, study the lateral branches and especially those that hang out into the street.  Identify those branches that absolutely have to come out and those that with a little pruning can be retained and still meet the code limits.  Then, prune all offending branches back to their origin.

With all of this said however, many safety issues needing correction in the landscape can generally be traced back to improper plant selection and placement.  If we have done our homework, we will know that mesquite trees have the capacity to grow up to 30 feet tall and as many feet wide.  Knowing that, we can properly select a planting site where the tree will not later in life cause problems on rights-of-way.  While I hate to say it, a tree or shrub that cannot be trained properly for public safety may just have to be removed.

Human safety is of paramount importance in any landscape.  Correcting any situation that can lead to injury is important and helpful when done in the right 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, Arizona 85122.  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 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Feeding Damage on Agave sp.

The feeding damage on the agave leaf shown in the photo is the latest of several similar examples that have come into the Cooperative Extension office here in Casa Grande, Arizona, USA.  The leaf shows hollowed out sections on the inner surfaces and missing sections at the leaf's margins.

The temptation, of course, is to blame an insect for the damage, but there are no known insects that would cause this kind of damage to agave species here in the Sonoran desert.  The agave snout weevil larva is a known pest on agave here but it is an internal feeder and causes an entirely different set of problems.  Typical agave snout weevil damage causes the drying and collapse of the entire plant.

The damage shown here is probably caused by a small mammal, such as a ground squirrel or more likely a small plant feeding rodent.  While we have not been able to positively identify the animal causing the damage through direct observation, we are fairly sure that we are on the right track.

Plants showing this kind of damage are typically younger and smaller plants, so it may be that as a plant ages and matures, the leaves become less attractive.  If we can get some growth on the plants, we should obtain relief from the feeding.

One way to protect the plant from further damage is to build a frame over the plant and drape the frame with bird netting.  Wire fencing is sometimes recommended to protect plants from vertebrate damages, and it works particularly well with rabbits, but fencing seems to be less effective against smaller animals because they tend to climb over the barrier.  Bird netting appears to work better, perhaps because they fear becoming entangled in the clingy mesh. As the plant matures, the netting can be removed.

If you would like to discuss this further, call one of our Master Gardener volunteers at 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
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Ten Signs That A Tree Is Planted In the Wrong Place

Planting a tree in a location where it will fail to thrive, or where it will become a nuisance, can be a costly mistake.

Trees, shrubs and bedding plants provide many benefits to a residential landscape, including beauty, shade and a welcoming feel to outdoor living areas.  A handsome, functional landscape also adds value to the home and can put extra money in the pocket when the home is sold later on.  In order to maximize these benefits, it is important to properly plan, install and care for the landscape.

Unfortunately, far too many mistakes are made at planting.  In horticultural terms, it is a mistake to plant a tree where soil or environmental conditions will not favor good growth, where it will eventually need regular and heavy corrective pruning or where it may need to be completely removed within a few years.

Heavy corrective pruning destroys the natural form and beauty of the tree and opens it up to possible infection by plant disease organisms and insect pests.  Removing and replacing a tree results in the loss of the plant’s immediate value.  It also means a loss of the valuable time required to bring the tree to maturity.  By taking the time to do the project right the first time, the owner or manager of a valuable landscape can save both time and money.

Here are ten common signs that a tree has been planted in the wrong place.  If you are getting ready to install a landscape, a good first step would be to take a drive or walk into any residential or commercial area and learn to recognize these mistakes. Then, as you plan your landscape, make sure that they do not show up in your yard.

Sign number one: the tree is growing into a power line.  Tree limbs growing into electrical lines strung from power poles can be dangerous hazards to people and property.  Maintenance crews regularly trim out branches that grow into and around these lines.  Trees that have been trimmed for safety often have their natural form, and their value, either seriously damaged or destroyed.  Many times these trees end up being removed completely.  When siting a tree, place it in a location where it will can grow in its natural form without danger of growing into power lines.

Sign number two: the tree branches grow into the street.  Planting a tree too close to the street will cause the tree eventually to spread its branches into a place where bicycle, car, and truck traffic will either hit, or swerve around, the branches.  In either case, the tree becomes a safety hazard that will need to be severely pruned or removed.

Sign number three: the tree limbs and branches grow over the fence into the neighbor’s yard.  If the neighbor doesn’t mind the tree or the shade that the tree provides, this may not be a problem.  More frequently than not, however, the people next door would prefer that a tree not invade their space.  The hassles, problems and potential conflicts that could occur are easily avoided  by planting the tree in a location where it will not cross property boundaries.

Sign number four: the tree branches rub on the exterior walls or the roof of the house.  Branches blowing too and fro in the wind can scrape and damage brick, paneled, or stucco walls.  They can also rip asphalt shingles or break tiles on the roof.  Plant the tree away from the home to avoid expensive repairs.

Sign number five: the trees grow into each other.  Trees planted too close together compete for water, air, nutrients and sunlight.  A lack of proper nutrition or sunlight will often stunt plants and weaken their trunks and branches. Branches that cross and rub against each other can easily be damaged and ruined.

Sign number six: the tree is damaging water, sewer, or natural gas lines.  Some trees have aggressive, fast-growing roots that can overpower and damage underground utility lines.  Sewer pipes are particularly vulnerable, for example, to the invasion of mulberry tree roots.  Depending upon the type of line, the damage can range from a mere frustration to one of real danger.  It is important to know where the lines are on the property, and avoid them.

Sign number seven: the trees shade out lawns and flower beds and make them unproductive.   Dense shade from large trees will often prevent lawn grasses, bedding plants, shrubs, vines and other trees from properly growing as they shade out their smaller competitors. 

Sign number eight: the tree is in a place where it can heave and buckle sidewalks and fences.  The roots of large trees, if they grow too close to the surface of the soil, can push up sidewalks and fences.  This type of structural damage can be difficult, as well as expensive, to repair.

Sign number nine: a caliche layer or structural hard spot in the soil causes the roots of trees to grow up close to the surface of the soil.  Shallow, improperly rooted trees can more easily blow over in a windstorm.  This problem can be avoided by checking the percolation of water through the soil prior to planting and by properly preparing the planting hole.

Sign number ten: the tree cannot be properly irrigated in a timely manner because water on the property is unavailable or is too expensive for the budget of the person paying the water bill.  Trees will become seriously damaged, or even die, if they do not receive the proper amount of water during the growing season.

Planting a tree in the wrong location is one of the more obvious and expensive mistakes that is all too commonly made during landscape planning and installation.  By taking the time to plan and install trees properly, major landscape mistakes can be avoided.  This will result in savings of both time and money.

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 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 85122
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu

Mending Drip Irrigation Tubes

Ever cut through a drip irrigation line?  I have and it is not a good feeling.

There are few disconcerting, even sickening, feelings than to be shoveling merrily away in the garden and suddenly feel that distinctive “crunch” when you cut through a drip irrigation line.  When this happens you have three choices: 1) give up on gardening completely, walk away from the site of destruction, and find another hobby; 2) call someone to come fix the line, or 3) get out the tools and supplies and repair the damage.  Most of us, after having gone through the “Oh, no!  What have I just done!” stage, select number three and get it done.

Even if you are one of the lucky ones and have never sliced through a drip line, it is still a good idea to regularly make sure that all is working properly and, if not, conduct regular maintenance.  Because plants depend upon the irrigation system for life-giving water, the overall success and health of our plants is dependent upon how well the system functions.  Good maintenance is a key to garden and landscape success. Finding plugged emitters, broken lines, or clogged filters during the heat of summer is no fun, and regular maintenance during cooler weather will often prevent these mid-summer hassles.  Still, accidents happen and damage occurs.  With plastic drip irrigation systems, repairs are usually fairly simple. 

First, locate the exact site of the problem. If the tubes are underground, a sure fire test for cuts or tears in the delivery system is to look for water soaked areas on the surface of the soil.  Water escaping from a line under pressure will soak through to the soil surface and create a boggy area that is much more moist than other areas around it.  Excavate the irrigation line by digging carefully down to the tube and search for a cut or slice.  If you have an above ground system, look for geysers spraying into the air.

Once you have found the exact site, you next have to decide how best to repair it.  For simple slices or nicks, couplers are the best way to go.  To save time traveling back and forth to the store for the correct parts, it is a good idea to plan the repair job first and then assemble a parts list.  This is also the time to decide on what tools you will need.  Hunt them all up and have them ready to hand before starting the project. 

The biggest challenge to quick and easy repairs is to have the correct-sized parts on hand.  It does no good to have a three-eighths coupler to fit a half-inch line.  It just won’t work.  However, most drip tubing is of a uniform size which makes it easy to find the right parts.  It is always a good idea to double check everything before getting down on elbows and knees in the mud to do the actual repairs.

Once you have all the parts together, it is time to start the job.  At the point where the damage has occurred, use a sharp knife or small hand saw to make a straight up and down cut through the tubing.  This will make sure that all of the fittings will match evenly and seal tightly.  A cut that is uneven will leave a side with less plastic to plastic contact resulting in locations where leaks may occur.

Just about any plastic tubing can be easily repaired with slide on, or in, couplings that join the two ends of the tube in a water-tight fitting.  These couplings are available at any hardware or garden store that services drip irrigation systems. 

The barb coupling has concentric ridges on the outside and around each end of the coupling.  The barb coupling slides into the plastic tubing as far as the coupling will allow.  The barbs grasp the inside of the tube to provide the necessary tight fit.

A compression coupler is different in that it slides over the top of the plastic tubing.  Both compression and barb couplers take a little work to move them into the right position for a strong, water-tight fit.

Those who are experienced in making repairs generally agree that the compression coupler is the better way to go.  Even though they are almost double in cost over the inside-the-tube barb couplers, they seem to have a better track record of success.  This is probably due to the water pressure inside the tube.  As pressure builds, the tube expands or swells in diameter slightly.  For compression couplers, the increased pressure pushes the tube  even tighter against the coupler, and thus, creates a tighter fit.  On the other hand, the pressure tends to loosen the connection between the inside-the-tube barb couplers.

If the damage is in thicker-walled PVC pipe, slide-on PVC couplers will work for small breaks, but extensive damage may require the replacement of sections of pipe.  Remember that PVC must be glued together with an approved adhesive.

Damage to above-ground feeder lines or emitters are fairly easy to repair.  Most systems are designed to add or remove emitters easily.  Holes created for emitters or spaghetti tubing can be plugged by snapping in “goof plugs,” attachments that are designed to correct mistakes in the assembly process.

Sometimes drip system filters will become plugged with precipitated salts, algae, or sand.  Most filters can be removed and rinsed to ensure good service.  If the screen inside the filter is damaged, replace it. The filter is a critical part of the system and scrimping and “making do” can cause you many headaches down the road.

All drip irrigation systems need to be flushed out regularly to get rid of accumulated contaminants that might collect at the end of the tube.  At the end of each line, there should be an access point which can be opened to allow the water to flow freely.  Once opened, the water pressure should push out any contaminants that might be inside.

With a little know-how and some time, your labor-saving system can be back up and running just like new, that is, until you cut it again.

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, extensioin 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 85122
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu