COMMUNITY GARDEN CLUB, March 24, 2006
Presented by Kartar Singh Khalsa (Gurbani Kaur)
Written
and supplemented by Siri-Gian Kaur
DRIP IRRIGATION
Wow! What a lot Kartar Singh covered with us! Since there is so
much, I am dividing his “Fabulous Compost” information into another document.
He has also offered to put these drip irrigation systems in for us, or to help us plan them, or to deliver fabulous
compost—all as part of his great business! He is at 505-753-4516 and kartar@la-tierra.com.
He likes to get his 5
gal. per hour, non-pressure regulating emitters for trees at Home Depot in Santa Fe, and the rest of his equipment from the
wonderfully specialized store called The Firebird that is staffed by those who can give expert advice! It is at 1808 Espinacitas in Santa Fe,
off St. Michael’s Drive. They are at 505-983-5264 and www.thefirebird.com/irrigation.html. Kartar Singh also suggested
Dr. Siri Atma Singh’s favorite supplier www.dripworks.com who have a catalog as well. And
he felt that controllers made by Hardy are quite good. They can be programmed
for up to 12 stations or zones.
Lowe’s, Hacienda
and Cooks in Espanola also carry supplies for drip irrigation.
Also, Marshal McClees
who does gardening for a number of us can advise homeowners on how to set up their own systems. Or he can put in the whole thing. 505-795-1081 to set up a
visit time.
Quick Overview Drip Irrigation: main water sourceà
water outletà filterà division of the main water
flow into several different flowsà “on/off” mechanisms, whether
manual or automatedà pattern of feeder hoses over your yardà final water delivery through “emitters,” soaker hoses, sprinklers, etc. + continuing maintenance on the whole system.
WHY DRIP IRRIGATION?
The main purpose for putting
in drip irrigation is so that you don’t have to spend lots of time that you might not have, watering your garden or
yard, and dragging around the heavy hose to do it. Your system can be manual,
semi-automatic, or fully automatic. Although Kartar Singh did mention the joys
of zoning-out (meditating) while hand watering your yard with a single hose!
As we know, here
in this dry and often very hot desert area, where the native soil may not hold water, plants can dry up really quickly. And when that happens, of course they die quickly!
So simple.
So, our plants need regular,
appropriate watering. Here in NM, Kartar Singh told us that more water is usually
better than not enough water for our darlings. However our plants’ water
requirements change, such as over seasons, when rain comes—they need less of our watering, and when the sun is really
piercing—they need more. And different plants need different amounts and
timing of watering. Drip irrigation can more easily help us fulfill their varying
needs, without over doing, and so consere precious water here in the desert.
However, his basic advice
to us for setting up our irrigation systems is KISS—Keep It Simple, Stupid! The
fewer lines you have and the fewer gadgets that you put in, the fewer repairs that are needed.
He emphasized that it
is important to regularly check your plants—at least 1 to 3 times per week to see how “everyone” is doing,
apprising not only their water needs, but also bugs, diseases, need for nutrition, pruning, dead-heading, weeding, thinning,
cultivating, staking, etc. And even if you have automatic drip irrigation, you
may make changes or repairs as necessary. Kartar Singh let on that checking your
plants regularly is actually a great joy of gardening! That is to stay in contact
with your little growing guys, to stayed tuned to their needs, and to take care of them—husband them to beauty and ripening!
DRIP IRRIGATION DESCRIPTION
- A WATER SOURCE, e.g your well or city water (chlorine does
not significantly affect most plants). However, salt treated, and softened
water are not good for your plants through. Irrigation ditches are usually used
to supply “flood” irrigation—that is flooding a whole field or lawn, as opposed to drip irrigation. Although with an electric pump to access the water, a ditch may feed drip irrigation.
If you have a well,
find out how many gallons per minute your well refills. You may have this information
on your well drilling paper work because that information is required by state law to be filed by your well driller. Or you can call the NM State Engineers’ Office 505-827-6120 that hopefully will
have that information on file. Without that, you can get a well drilling business
to test that for you. A normal rate for your well to refill is 10 gal. per minute. Some do more, some less.
- A WATER OUTLET that comes from the source such as a spigot from
your house, or a freeze hydrant—those tall spigots whose rigid PVC water supply pipes are buried 2 ½ feet deep
so that they don’t freeze. Freeze hydrants may be located in or near your
garden. These may be fed from your well or from the plumbing that comes to your
house. Or pipes from your water source may directly feed a multiple valve
system.
- A FILTER to take particulate matter, e.g. sand and dirt out of the water
so that it will not stop up the tiny holes in the apparatuses that actually put water on your plants. These vulnerable watering dispersers (emitters, sprinklers and soaker hoses) are located at the terminals
of your watering system at the far other end of your water lines. This filter
may be installed at a point in your water delivery system that comes after your main water source, but before the division
of your main water flow as described next. It is usually done at the well. In this way, you only need one filter to protect of all your lines. And be sure to clean or replace your filter regularly.
- DIVISION OF THE MAIN WATER FLOW into several hose lines so that each line
feeds a different area or “zone” of your yard, or a zone may be a specific group of plants, lawn, trees
or shrubs that have similar water needs. But if you just want to water a small
garden, you may use only one line off your spigot or hydrant.
We learned
last fall that Tarn Taran Kaur screws an attachment onto her spigot or hydrant. It
divides the water flow into 2 or 3 “hose bibs” (where you screw your hose on), allowing her to get water
flow from multiple hoses which are all emanating from the same main outlet.
Or, you, or
someone that you hire may set up a valve system that separates your primary water flow through a compact pattern of
rigid piping that supplies a number of valves. A “header” or “manifold”
is comprised of multiple valves, perhaps 3 to 6 that may be installed about a foot below ground level in a protective plastic
“box” with a lid that opens to the surface. If you have a really
large yard, you may need additional headers.
Then the same number
of feeder hoses, each attached to a single valve carry the water flow from the other side of each valve, and then out to specific
zones of your yard and gardens. If you don’t want to create lines from
all of your valves just yet, you can plug the unused ones until you are ready for them.
This works to create an expandable irrigation system.
If the water flow
through each feeder hose can be turned on and off independently from the other hoses, you don’t have to send huge quantities
of water through your whole irrigation system all at once to all areas of your yard.
If you did, that could drain your well, lowering your water pressure and so cutting down on the amount of water that
can flow everywhere at the same time, including the water to your house. And
taking too much off your city water line at the same time may lower your water pressure as well.
So, if you
can turn each feeder hose on and off at specified times, thereby controlling watering times—varying the length of time,
days that you water, and time of day that you water, you can arrange to send varying, most appropriate amounts of water to
different plant areas at advantageous times. For instance, you can soak your
trees well with lots of water once or twice a week, and then let them dry out so their roots don’t rot as they might
if they were continually wet. And you could water lawns with a sprinkler everyday
before sunrise to cut down on evaporation as well as not cause the sun to burn the grass blades when shining through the water
drops (similar to making a fire when focusing sunlight through a magnifying glass).
And still other lines may dispense lighter amounts of water with less watering time, but be turned on more frequently
as the water is applied to the base of tender plants. This might be done at the
times of day that the plants are most thirsty, and doing this regimen daily.
On And Off Operations—Timers and Controllers:
Now obviously,
spigots and freeze hydrants are turned on and off by hand. You
can do that, or you can make their operation automatic, so you don’t have to spend a lot of your day, every day turning
your various feeder hoses on and off at different times.
You can automate
your spigot or hydrant based system by connecting a programmable timer to each hose bib (which may be a multiple hose
bib with multiple timers), then attach your hose(s) to the other side of the timer(s).
These timers can be battery operated or even solar powered, and will turn the water going to the hose attached to it
on and off at the times (and perhaps the days) that you program into it. Consequently, you leave the main tap on manually,
and let the timer(s) automatically turn the water on and off to each feeder hose.
There are also very
simple twist, wind-up action, countdown timers that work like a kitchen timer to turn the water off after the amount
of time that you set is spent. But you need to set them each time you water,
because they do not turn the water on.
A homeowner’s
valve system is based on an electronic, programmable “controller” that will give you a wonder of
options for turning each valve on and off independently. This is accomplished
by connecting electric wires from the controller to each valve, using DC current so there is no electric shock when they get
wet. The electric signals from the programmed controller command the “on”
and “off” switches on each valve. So, the electrically operated valves
act as gates that turn the water flow on or off. Therefore,
each valve controls the water flowing through the feeder hose that is connected to it, consequently controlling the water
supplied to a specified area of your yard or garden, or a group of plants with similar waters, each defined as a “zone.”
With the controller,
you can program each valve to automatically control its associated zone separately to: water a certain number of times per
day at particular times; water only on specified days of the week; you can keep some unused valves turned off until you install
feeder hoses to them; or you can switch to manual operation for a time so you can turn the whole system off and on by hand
if, for example you have a lot of rain and don’t need irrigation that day, or if it is particularly dry, you might want
to give extra jolts of water in addition to your programmed applications; and so on.
And to give
great coverage to your yard from a well—they all have limited water output, you can plan to run each zone at different
times so that your well can fully supply each your zones when done at alternating times.
You can even extend your watering day by setting a zone to water the base of some plants at night, not on the leaves
though. If you let water sit on the leaves most every night, you can encourage
mildew on your plant. Or, you can sprinkle your grass just before sunrise so
that it will dry off in the soft rising sunlight.
With this zone system
you can create a complex watering system that best suits each of your garden’s and plant group’s watering needs,
plus provide for your well’s optimum operation, and it will be automatic—decreasing stress and time spent, and
you can even take a vacation during the growing season without your whole yard turning crispy!
A controller has
a battery backup so that if you have an electric power failure, your programming is not lost.
So, be sure that you keep a fresh battery in it. Although most controllers
have a “fail-safe” back up so that if your battery is low, they will water each line for 10 minutes each day if
your controller is set in automatic mode.
However, the controller’s
actual operation of the valves is dependent on 110 Volt house current. So, if
your power goes off, you don’t have irrigation for that time. Your electric
well pump won’t work for that time either!
- SYSTEM AND PATTERN OF FEEDER LINE COVERAGE.
It is very important to plan out how you lay your feeder hoses.
First, the “upstream”
rigid pipes that carry water from your main water source TO your on/off mechanism—manual spigot, or automatic timer
or valve will be larger than, or the same size as your primary flexible poly plastic feeder hoses that move water AWAY FROM
your on/off controls. These first flexible feeder hoses in your system should
be the largest hoses that you use—usually ¾” to ½” in diameter.
Stepping down
the size of your hoses in your system as you move away from the source to the terminals keeps up the water pressure, insuring
that water flows out on your plants at optimum levels. If you do the opposite,
you won’t get water flow.
So, for example,
your first feeder hose in a line may be ¾” in diameter. But then you can
connect several smaller hoses, e.g. ½ ” diameter at different points in to the larger hose down-line. This way, you can create a pattern of hoses that will spread out to reach all your plants in a similar
location, or fan out to those that have very similar water needs while keeping the water pressure up.
Kartar Singh pointed
out that some irrigation systems are based on involved pressure differentials, but he sticks to the simple “volume”
method of drip irrigation, which will work great for us. This type alters the
amount of water you get from a consistent water pressure by the length of time the water runs, combined with the quantity
of water distributed by the final delivery apparatuses (described in the next bulleted section).
To keep your pressure
consistent in the length of your lines, you can put smaller volume emitters upstream on your line, with larger volume emitters
towards the end.
Feeder Hose Planning
Now, your
larger feeder hose lines that are each controlled by their own on/off mechanism can be extended out to serve your patterns
of same size and smaller “local” feeder hoses. These “local”
feeder hose patterns are laid to best accommodate watering to both near and far locations of your garden and lawn areas, as
well as serve the group water needs of your various plants. And too much pressure
in a line can cause it to crack. Put some thought on paper on how you might group
these. Then create defined hose patterns to best serve your specific requirements.
In addition, consider
equalizing your water distribution among all your zones. For instance you might
not want to overload some zone lines—especially if they run simultaneously, while other lines run far under their capacity. But use your best judgment to figure this out.
All these following descriptions are only examples to spur your creativity. Take
in the basics and make your own plan!
Kartar Singh says
that your irrigation system doesn’t have to be perfect, and that it is not rocket science! You can improve your system over time as you see how it works for your garden.
Feeder Hose Placement and Connections
All these feeder
hoses—both primary and local usually lie on top of the ground so that you can see them when you check their operation,
as well as dig around them. Although Rand Lee
suggested that they can be mulched over to protect them from deterioration by the sun.
If they are buried underground, you may forget where they are and accidentally dig into them. Woops!
On the other hand,
Siri Hari Kaur has a completely buried irrigation system where the plant roots are watered underground. No irrigation equipment is evident. However, this appears
to be more of a high-end, park-like approach that is unusual in this area.
To connect your
hoses, you can use appropriately sized rigid plastic hose “barbed fittings’” also called “connectors”
that are inserted into the cut ends of each hose that you want to connect. The
size of each end of these connectors that corresponds to the sizes of the hoses that you want to connect will be printed on
the package. So, for example you may have a ¾” nib on one side of the connector
and a ½” on the other side. Or each side of the connecter may be the same
size if you are simply extending the length of your same sized line. And although
these connectors make a pressure-tight bond with your hoses, you may also want to screw a metal strap clamp around the hose
where the connector is inserted to hold the connection firm over time.
Now, perhaps
you have created a rectangular vegetable garden with a number of rows running along the greater length. Then you might run your larger diameter feeder hose along a shorter side of your garden, and then connect
smaller hoses at right angles, placed so that each smaller hose is laid down the length of each row. That way, water can reach every plant (through terminal feeder apparatuses that are described in the next
bulleted section) in every row.
To hook this “row
pattern” up, you can use “T” shaped connectors in your line. In
this case, you cut the larger hose where you want to connect in a smaller hose at a right angle. Then you use your “T” shaped, appropriately sized connector to attach the 2 cut sections of
the larger hose in a straight line. Then attach the smaller hose to the right angle nib on the “T” connector. Plug the hoses into the connector as described two paragraphs above. Then, once you have covered your vegetable garden with smaller feeder hoses, and if you don’t want
this larger line to continue beyond to other parts of your yard, you would cap off that far end of the larger hose, as well
as cap the ends of each smaller “row” hose to prevent water from escaping where you don’t want it to flow.
Or, if you
have a line or area of plants that have similar water needs, you can run a feeder hose just to them, such as to a line of
trees, or connect soaker hoses winding through an area of ground cover or dense planting, or to all the sprinklers for a certain
lawn area. You can make any pattern that seems to distribute water in a logical
pattern for your plants’ requirements.
If you till your
garden every year, you can put in a non-permanent hose system, so that it can be removed every year in the fall and stored
in your garage. Then you can raise a “green manure” crop in your
garden in the winter, such as an annual grass like winter rye, oats or buckwheat. Then
till the crop under before it goes to seed. Or till only your rows where you
want to plant, leaving the grass crop between the rows to keep the weeds down.
Once you get
the feeder lines laid in your yard, perhaps concentrating on just one main feeder line system or zone at a time, then you
can begin to insert the apparatuses that will actually put water on your on your plants.
There are several different kinds as you will see below.
When planning
your various zones, consider how many of each kind of emitter you will use on each plant.
Then you can figure the actual water outlay for that zone. For instance,
if you have a quantity of 120 of 5 gal. per hour emitters on one zone, you are
putting out 600 gal. per hour. Divide that by 60 minutes in an hour, and you
are pulling 10 gal. per minute from your well, which is a normal refill rate for a well.
That is really simple math.
Also, the
length of the feeder hoses, the number of “gadgets” such as emitters, tiny tubing, elbow shaped connecters, etc.
tend to slow down the flow some through “friction loss,” so you can just intuitively figure that in.
I suspect that coming
up with this overall balance to create your water flow is what seems most puzzling about setting up an irrigation system,
but Kartar Singh is very encouraging about our working it out! And once you work
with it some and get a feel for it, it won’t seem so very mysterious. If
something doesn’t work, you can always change it! No big deal.
Emitters
These are
usually quite small plastic “things” that allow a certain amount of water—according to a particular emitter
design to escape from it when the water in the feeder hose is running. They are quite water efficient because your can control
the amount of water they emit, and you place the emitters so that they will put water just where you want it—directly
onto the plant roots. Consider that tree water-collecting roots are further from
the trunk than the roots of shrubs and smaller plants that may be closer in.
Since it is sometimes
impractical to place your feeder hose directly by every single plant, you can use tiny ¼” plastic tubing, also formally
named “spaghetti tubing” to move water from a fairly straight or curved feeder line an extra, rather short distance
to deliver water through the tiny tubing’s terminal emitter directly to your plant.
Or you may want to circle your plant or tree with a feeder hose and plug several emitters (with or without tiny tubing)
into it for greater water delivery.
So, emitters are
either plugged directly into your down-line “local” feeder hoses, or into one cut end of tiny tubing that has
been plugged into your local feeder hose on the other end.
To plug either
an emitter or tiny tubing into your feeder hose, you use a special tool to punch a hole into the side of your feeder hose
where you want to insert either kind of equipment.
Then to attach the
tiny tubing, first cut your tiny tubing to the length that you need. Next plug
one end of a tiny connector into the hole you made in the feeder hose, and plug the other end into a cut open end of your
tiny tubing. Then you can insert an emitter either into the other end of the
tiny tubing; or without using tiny tubing, you can plug an emitter directly into the hole you made in the feeder hose. Emitters have their connectors built in. Put
as many of these emitter set-ups on your feeder line as you need to adequately water each plant with one or several emitters.
There is a variety
of these emitters. Kartar Singh prefers non-pressure regulating, 2 to 5 gallon
emitters for large trees. This means that these emitters will allow 2 to 5 gallons
of water per hour to flow out of it to give a good soaking. He puts two or three
of these around each large tree. He likes this kind of emitters because when
they inevitably get clogged with white calcium minerals, he can take them apart and scrub them with a brush and soap and water,
or drop them into white vinegar to dissolve that calcium scale.
And he suggests
½ to 1 gallon emitters for flowers.
Some other
kinds of emitters are called “flag emitters” that have a tiny flag-like tab on the top that you can twist to change
the amount of water that flows from it., and you can also turn them off. You
might need to turn it off perhaps if that plant dies or you don’t plant anything by that emitter that season, but you
still need to plug that hole in your feeder hose. You can also break calcium
deposits with this twist action.
There is another
barrel looking kind attached its own tiny tubing that emits a small sprinkler action, and can again be twisted to emit varying
amounts of water. Another sort of emitter is set on top of a tube that is held
vertically about 6” inches above the earth surface. It emits a horizontal
spray in a half circle pattern to cover dense plantings on one side, but not spray your walkway or beyond your garden’s
border on the other side. And there are lots more special use types as well for
you to explore!
For a guide from the Santa Fe Botanical
Garden on what size emitters to use with various plants, and how to place them, please go to http://www.santafebotanicalgarden.org/subpages/garden%20drip%20irrigation.html.
Soaker Hoses
These are hoses
that allow water to escape along their length, but because you can’t control their water output very well, they use
a lot of water and so may be inefficient. They are particularly good for areas
that are packed with plants, a continuous line of shrubs, to wind through a patch of groundcover, or to encircle a large tree
or shrub.
Some soaker
hoses may be porous along their entire length, being made from recycled rubbers tires, and these are the same diameter as
a garden hose with the same kind of screw on connectors at both ends.
Or a soaker
hose may resemble either feeder hoses or tiny tubing but have tiny holes drilled in them at various intervals along their
length. For instance, one kind of soaker hose is 1/2” in diameter, with
a very small hole placed every foot. It may replace a specific portion of feeder
hose and circle a tree or shrub, snake through a garden, or feed a line of shrubs. The
whole feeder hose will continue to operate as well as it did before this soaker hose was inserted in its length.
Kartar Singh prefers
a kind of soaker hose that is made of ¼” tubing with laser cut holes every 4” to 6” inches, and may run
20 to 30 minutes per day. This can be attached to a feeder hose just the same
way you attach tiny tubing that is described above. It can meander through a
garden or groundcover area, or water a whole row of closely planted vegetables.
Sprinklers
These are the large
or medium sized apparatus that most of us from other locations are familiar with. They
spray water from a sprinkler head that can be set to either spay in a full circle with the sprinkler at the center, any width
of an arc of that circle, or the spray remains stationary to one location. Even
sprinklers that are attached to garden hoses have this range of capability. And
you can usually adjust the length or radius of their spray by setting the water pressure that flows through them.
Sprinklers around
here appear to be used primarily for lawn areas and perhaps for some fully packed gardens.
This is because lawns need full, even coverage over a fairly large area. The
drawback here in the desert is that when you use them, especially in our dry heat, a good percentage of the small sprayed
droplets evaporate into the air. And, of course, they put out a lot of precious
water. But there doesn’t seem to be any better way to water a lawn, which
is why many people in this area prefer to conserve water by using xeric (low water need, often native) plants, or other more
widely spaced plants that consume less water.
There are
different sizes and styles of sprinklers that you can use in your drip irrigation system, either singularly or several in
a pattern to gain the best coverage. One style is the “pop-up” variety. When no water is flowing through the feeder hose that it is attached to it, the dormant
sprinkler head sinks down below ground level into a tube that is inserted into the earth.
When water to the feeder hose is turned on, the sprinkler head pops-up, or raises a number of inches above the cut
grass to spray the area that you have set for it to water. So, you can either
place these pop-up sprinklers in the middle of your lawn so you get good coverage and don’t trip over them; or place
them around the lawn perimeter, also giving good coverage, and they are not unsightly when not doing their work.
You attach these
pop-ups to your feeder lines with connectors as already described. However, you
may need to bury these feeder hose connections if you put them out in your lawn, or mount them on stakes if you put them above
ground in non-traffic areas.
Another kind of
sprinkler is one familiar to agricultural irrigation—that is a “rain bird” or “impact head”
that ratchets back and forth as the head moves around on its center. This may
be a fairly small instrument and situated on the side of your lawn or garden so you don’t trip over it. Or it can be a high capacity sprinkler that is mounted on a several foot tall feeder pipe so that the sprinkler
head can clear the growing plants it sprays, and its powerful spray can reach wide areas.
- WINTER AND GROWING SEASON MAINTENANCE
Anytime during the
year, you can simply replace individual emitters, soaker hoses or sprinklers if they break or clog. You need to keep watch on those water delivery devices as well as on your hoses, hose connections and on/off
mechanisms regularly to be sure they stay connected, remain in tact and unclogged and sprinklers are unstuck over time. You will know that something has come apart if you hear heavy running water, or see
a single fountain of water squirting up, or you find a big puddle where it is not expected.
On the other hand, if you find plants wilting, check for broken or clogged irrigation connections.
And especially when
setting your system up again in the spring, the whole system needs to be checked and repaired.
In the fall, before
we have a real freeze, it is really important to cut the water to your irrigation system off at the source (valve systems
usually have a special turn off valve to the whole system). If the water in the
pipes or hoses freeze, the forced expansion may break or put holes in your equipment, and it can force connections apart,
so it is good to drain your hoses. However, flexible poly plastic feeder hoses
are freeze tolerant so they can stay in your garden. This is the time of year
that you also turn your swamp cooler water off and drain its line for the same reasons.
If your cooler line springs a leak that you don’t correct right away, it can create a huge iceberg on your roof
whose weight can finally crash through your ceiling!
If you have individual
timers connected to garden hoses, or removable soaker hoses you might like to store all these under shelter for the winter
to lengthen their lives. Otherwise, your valve system and array of feeder hoses,
tubing, emitters, more durable soaker hoses and fixed sprinklers will probably remain in position over the winter.
Or, as has been
mentioned, if you have a non-permanent system of hoses, and you intend to till that garden in the spring, you can remove your
hoses for the winter and store them inside. This will save the hoses better,
and you can till in the spring unimpeded.
Then when spring
comes, if you need to turn the water on early in the season to water dry plants, be sure to turn your system off and again
and drain the lines before nightfall when the temperatures drop. However, it
may be easier to simply hand water everything with a garden hose instead of going to all that trouble with your drip irrigation
during these possible freeze nighttimes with their growth promoting warm days. Or
pray hard for soaking rain as we had recently!
