Your guide to installing and maintaining  low-pressure  trickle drip irrigation parts and systems
 
     
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Here are answers to the
most frequently asked questions
about Drip Irrigation 



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TM8 Timer is reducing pressure

How do I install compression fittings easily?

How do I tell if my drippers are delivering the right amount of water?
My drippers are not delivering enough water. What now?
Will a little dirt hurt my drip system?
Can I turn my drip system on by hand each day?
Can I join pipe threads and hose threads together?
My TM8 timer won't shut off at the end of the cycle
Can you look over my order to see if I have missed anything?
Do I need to use teflon tape on the threads?
Is drip irrigation suitable for prairie farm shelterbelts?
How does a slight change in elevation affect a drip circuit?
How do soaker hoses compare to dripline?
Is drip irrigation OK for low-pressure gravity-fed water systems?

Will drip irrigation work on hillsides?

Can I increase crop yield with drip irrigation?

How much water can I save with drip irrigation?

How can I bury tubing under a sidewalk?

What are the disadvantages of drip irrigation?

How frequently should my drip irrigation be turned on?
How long should I keep the drip circuit turned on?

There is only a small wet area at each dripper, is it working OK?

Why do I need drip irrigation when there is enough rain?

My 1/2 inch tubing kinked when laying it out. Is that a problem?

Will my drip irrigation system take frost?

How long will my drip irrigation system last?

Can I use drip irrigation indoors?

How do I uncurl my roll of tubing?

How do I insert barbed connection fittings into tubing?

How do I get rid of hard water deposits?

My Deluxe Punch sometimes fails to cut a clean hole

When should I use sprayers instead of drippers?

There isn't enough room under the faucet to hang all the drip parts.

 

My TM8 Timer is reducing pressure in the system
3 If your drip system is running on reduced pressure when you add a TM8 Digital Timer, make sure that the timer is the first component attached to the bib faucet. If your V4HD anti-syphon valve is first and above the TM8, the screen in the inlet of the TM8 can press against the lever in the bottom of the V4HD, cutting pressure to the system. You can also turn the screen in the top of the TM8 over so that the screen will not interfere with the V4HD.
How do I install compression fittings easily?
3 Use heat. Pour some boiling water over the tubing and then twist the compression fitting back and forth to push it onto the tubing. It's difficult to install compression fittings if the tubing is cold and stiff. We pour some boiling water into an old vacuum thermos to take when installing. We loosen the lid and pour enough hot water on the end of the tubing to soften it. Make a mark with some chalk or crayon on the tubing so that you can see when the tubing is inserted about 3/4 inch into the fitting.
How do I tell if my drippers are delivering the right amount of water?
Leave the tubing in place and dig a hole in the soil under one dripper large enough to put a coffee can or something similar to catch the total flow from the dripper. Make sure that all the water from the dripper goes into the collection container and does not run down the tubing. You may have to twist the tubing to get the dripper pointed down. Measure the amount of water in the container after a specific length of time irrigating. You should have the same amount of water delivered as listed in the description of the dripper or dripline, for example one gallon for a D4 dripper which is rated at one gallon per hour.
My drippers are not delivering enough water. What now?
If you are losing pressure at the drippers, it can be dirt in the tubing, a kink or a break in tubing that is losing system pressure. It can also be too many drippers on one circuit. If you are installing a large extensive system, build the system one part at a time. Flush and test the first section or circuit before you go on to the next, especially if it's your first time installing. If you have installed a large system and have pressure problems, it's best to go back to basics. Isolate the first row, get it to work properly and then move on adding more rows. If you add too many rows to the circuit and the pressure drops, it's easy to back up in steps until the circuit is working properly.
Will a little dirt hurt my drip system?
Dirt is the enemy, it can plug drippers and sprinklers. When installing tubing, cover the open ends with tape until you are ready to join parts. Flush the head assembly after assembling the parts, flush the mainline when it's installed and flush the entire system before closing the ends and pressurizing the system. Each spring, open the ends and flush the system to get rid of fine sediment that accumulates. Keep drippers and the open ends of small diameter tubing above the mud or muddy water. If dirt gets in, it's hard work to get it out. If you keep dirt out of your system, you will have few problems.
Can I turn my drip system on by hand each day?
Yes, of course. Especially if you work in the garden every day and make it a part of your routine. But if you are like the rest of us who are busy enough to forget, we recommend adding an automatic digital timer. When you water by hand, if you forget to turn off the drip system, you may end up wasting water and inducing runoff while it runs for a day or more. If you forget to start it on a hot day, your plants may suffer the shock of not enough water. With an automatic timer, plants become acclimated to a precisely delivered drink of water on a regular schedule. Use a digital timer and you do not have to remember to start and stop the system, and your plants will grow at their maximum rate.
Can I join pipe threads and hose threads together?
No. If you try to join hose and pipe threads, one set of threads will strip and the connection will leak. If you have the two thread types in front of you, the coarser thread is the hose thread. The finer thread is the pipe thread. If you need to join them, use adaptors to make the conversion. We offer many adaptors in our online drip irrigation store under Fittings.
Hose threads are always 3/4". Pipe threads come in all sizes. You need to add teflon tape to pipe threads to keep them leak free. You don't need to add any teflon tape to hose threads since there should always be a rubber washer to seal the joint. An example is your garden hose which is always hose thread. In our online store, we mark each part with an icon to show whether it is pipe threads irrigation systems or hose threads irrigation systems.
My TM8 timer won't shut off at the end of a manual cycle
If the water pressure is greater than 80 PSI, the valve cannot close. The solution is to have your building staff or a plumber reduce the water pressure to 50 or 60 PSI at the faucet, closer to normal household pressure. Avoid trying to place the pressure regulator ahead of the timer to fix the problem. That would cause the regulator to wear out prematurely. Pressures higher than 80 PSI are common in hi-rise buildings. Another possible cause is having programmed cycles turned on at the same time that you have keyed in a manual cycle to open and close. Check your programmed start times by going through the setup procedure.
Can you look over my order to see if I have missed anything?
If you are not sure that you are ordering the right parts from our online store, mention to us in the Comment section of the Checkout that we should hold the order and check it. If you give us an idea of what you are trying to accomplish, we will look over the order and suggest parts that may be needed. Many times we can save you the time and expense of making a second order to complete the job.
Do I need to use teflon tape on the threads?
There are two types of threads on drip irrigation equipment, hose thread and pipe thread. Hose thread is the coarser of the two. If you try to join hose and pipe threads, one of them will strip out. On hose threads, no silicone tape and no sealants are required and almost all of our items are hose thread. There is usually a rubber washer with hose threads, a good example is your garden hose. You never need to use tools on our drip irrigation fittings. Hand-tighten only. Small leaks are common with drip irrigation fittings, no matter how tight, one reason they should never be used indoors. On items with pipe threads, use three wraps of teflon pipe thread tape from our online store for irrigation products.
Is drip irrigation suitable for prairie farm shelterbelts?
Drip irrigation is ideal for starting and growing shelterbelts. Once the trees are mature, drip may no longer be needed except in very dry regions. Wind has no effect on drip irrigation and you can save up to 50% water compared to sprinklers. Drip is easy to automate and divide into a number of circuits that turn on at different times of day. That takes the load off pumps and low-recovery wells. Drip irrigation also encourages deep roots necessary for shelterbelts.
How does a slight change in elevation affect a drip circuit?
Try to keep the supply tubing for a drip irrigation system at the high point of a slope. Any time that water has to be pushed uphill, water pressure is lost and the branch lines must be shorter to compensate. If water runs down a slope, you can extend the length of the circuit because gravity is compensating for some friction loss in the tubing. A 5 foot elevation change in a yard won't matter much but anything more will make a difference with irrigation systems. Always use pressure-compensating drippers if you have changes in elevation on the site over 5 feet.
How do soaker hoses compare to dripline?
Soaker hoses work but it's difficult to control the rate of flow. Dripline has a very slow and exact rate of flow for better penetration of the water to root depth. Soaker hoses come in fixed lengths that are difficult to fit to various garden beds. In contrast, it's easy to cut and fit dripline to any shape bed using fittings for corners and connections. Dripline can also be integrated with other drippers and sprayers on the same circuit. Dripline has a turbulent flow at each dripper that reduces clogging from silt. Soaker hose has no remedy for clogging and uneven distribution of water is the result.
Is drip irrigation OK for low-pressure gravity-fed water systems?
Yes, but choose non-compensating drippers and dripline if the water pressure is less than 10 PSI. Pressure-compensating drippers require about 8 PSI to open but our flag drippers (D2) will flow at 4 PSI and are best for low-pressure water systems. Our DL4 dripline is also non-pressure compensating and suitable for gravity systems. Experiment to see what your gravity system can irrigate. Attach up to 30 drippers on the system and note the flow from each. Attach another 30 and see if the flow rate is significantly lower. Adding and testing is the best way to see if the pressure is degrading, common to very low pressure systems.
Will drip irrigation work on hillsides?
Yes. Because drip irrigation delivers a slow trickle of water to the roots, problems with runoff, erosion and uneven distribution can be eliminated. Be sure to use pressure-compensating drippers such as our D4, D5, D6 or D7 that deliver a precise amount of water at the varying pressures found in a hillside system. Keep all drippers slightly uphill of the plants they serve. Air relief valves may be installed at high points to avoid suction of dirt into the system on shut down. Water should be supplied to the system at the top of the hill and allowed to flow through branch tubing on the way down the irrigation systems. See the How-To article for more.
Can I increase crop yield with drip irrigation?
Yes. Drip irrigation provides a consistent supply of water to the entire root area on a continuous basis so that "drench and dry-out" stresses are reduced. Root growth is encouraged and the result is a healthier plant at the fruiting stage and greater resistance to disease and pests. Drip irrigation keeps the leaves dry and can reduce fungus and mold problems. Consistent soil moisture maximizes growth at early stages and can result in early flowering.
How much water can I save with drip irrigation?
Drip irrigation saves up to 50% compared with sprinklers. The higher a sprinkler throws water, the greater the loss to evaporation and overspray. Sprinklers wet the surface quickly and when the soil surface is saturated, puddles form. As the puddles grow, water can flow downhill and cause runoff and erosion even though the subsurface may still be dry. Sprinklers often distribute the water unevenly with some areas too wet and others too dry. Drip irrigation solves the problem by delivering water slowly and under control to a precise area at the roots, with no appreciable loss to evaporation and none to overspray, runoff or erosion.
How can I bury tubing under a sidewalk?
Carefully strip the lawn back and dig a hole about 12" deep on both sides of the sidewalk where you wish to cross under. Slip the end of a garden hose inside a 36" length of rigid steel pipe a bit larger than the garden hose. Turn on the water and let the garden hose in the steel pipe flush a hole through the soil under the sidewalk using high water pressure. It's a messy job but all you need to do is apply steady pressure and the water will do the work. Work from both sides if you can. When the hole is complete, cap the tubing to keep out dirt and slide it through. Replace the dirt and lawn with the turf you removed.
What are the disadvantages of drip irrigation?
Drip irrigation is not suitable for watering large areas such as lawns. It operates so quietly that you have to check drippers to see if it is on. Small openings in dripline and drippers can clog with algae, silt or mineral deposits if there is insufficient filtration or a dirty water source. If the system is not buried, vandalism or damage by animals can be a problem.
How frequently should my drip irrigation be turned on?
That will depend on your soil. Sandy soils drain quickly, you will need to water more frequently and at a higher rate of flow so that the water wets the largest possible horizontal area. Clay soils need a slower rate of flow so that the water can penetrate down to the roots. Clay soils hold moisture longer so that you may only have to turn the circuit on every other day. Greenhouse operators turn on small quantities of water as often as every hour during the middle of the day. In all cases, do not allow the soil to dry out. The soil around the roots should always be slightly damp for maximum growth and fruit. See the How-To article
How long should I keep the drip circuit turned on?
For most plants, 45 minutes to one hour is time enough. If you keep the circuit turned on longer than that, gravity's pull on the water will make it flow down below the roots and the water is wasted. Of course, if you are watering trees with deep roots, it may take longer to wet the entire root area. Dig down to see. In hot weather, drip irrigate more often rather than for a longer period of time.
There is only a small wet area at each dripper, is it working OK?
Yes, that's the beauty of drip irrigation. The surface of the soil stays relatively dry, but if you dig down, you will see that an entire soil area from 18" to 36" wide and up to 24" deep will be wet. The drip irrigation water flows down and out by capillary action. And at such a slow rate that air is maintained in the soil unlike other irrigation methods that saturate the soil. Plant roots can be stressed if the soil is completely saturated with water. An added benefit of the dry surface is that you are not watering all the weeds nearby.
Why do I need drip irrigation when there is enough rain?
If you live in a coastal area with regular rain through the growing season, rain may be enough. But for all the rest of us, we have rainy periods and dry periods and it only takes a couple of dry spells to stress our plants. Plants prefer a regular drink of water, especially during early root and leaf growth and again while setting fruit. Plants irrigated by drip develop deeper, stronger roots, grow faster and develop more fruit than plants that suffer the drench and dryout cycle of seasonal rains. It's all a matter of giving the plants what they need, a regular and dependable drink of water at the roots.
My 1/2 inch tubing kinked when laying it out. Is that a problem?
No problem. We have tested our 1/2 inch tubing by kinking it 180 degrees at the same spot for 200 times with no visible weakening or splitting. So you could kink it repeatedly without a break. The only thing you have to do is make sure that the kink is straightened out before you turn on the water. Water will not pass through a kink in the tubing. Especially important if you are burying the tubing. Always use elbow or tee fittings when going around sharp corners with tubing.
Will my drip irrigation system take frost?
The tubing is not harmed by frost - it can stretch. But all the timers, fittings and connectors are rigid plastic and if water remains at the fittings when it freezes, the expansion of the water (ice) can break them. The best method is to drain all drip irrigation lines before frost. Battery operated timers should be brought indoors over the winter and the batteries removed. You can leave all tubing and fittings in place in the garden during freezing weather. Just make sure that the system is completely drained.
How long will my drip irrigation system last?
The service life of drip irrigation parts is determined by exposure to UV radiation from the sun. All the parts we offer are commercial grade and are designed to stay outdoors all year round. Our heavywall tubing has UV blocking ingredients and should last at least five to seven years in the most severe sunlight and twice as long if covered with mulch. Fittings and drippers should last at least as long. Snow cover in the winter can shield parts from the sun. Plant growth in the summer can shade parts and extend their life. There are small passageways in drippers, sprinklers and dripline. Always use a filter to keep sediment from clogging parts and avoid extremely hard water that may leave deposits in the system.
Can I use drip irrigation indoors?
No, drip irrigation parts are only meant to be used outdoors where a small leak will do no harm. Any indoor watering system should be installed by a licensed plumber and may require building permits and inspections as well as pressure testing at rates too high for drip irrigation equipment.
How do I uncurl my roll of tubing?
Leave the entire coil in the sun to warm up before you try to unroll it. Trap one end of the tubing under a fence or a heavy object and roll out the tubing on your lawn in the same way that the tubing was rolled in the factory. Leave any curls and avoid trying to straighten the tubing until it sits in the sun for a while. It will relax and begin to straighten. You may have to use shepard stakes to keep it in place in the garden but within a few days, the tubing will relax and conform to the shape of the ground. If the tubing kinks as you try to straighten it, don't worry, kinks will not harm the tubing. Squeeze any kink out with your hand. Water will not flow through a kink so be sure to use elbows or tee fittings to go around corners.
How do I insert barbed connection fittings into tubing?
In cool weather, pour hot water (140 degrees F) on the end of the tubing to soften it. Then the barbed insert will be easy to insert. We use an old thermos full of hot water but an old bucket would work well. As soon as the cold water flows through the connection, the tubing will shrink to a fit so tight that you should not be able to pull it apart. Push the fitting into the tubing past all barbs for maximum strength.
How do I get rid of hard water deposits?
Avoid very hard water if you can. Mineral deposits can build up in the small openings in drippers and other parts. Otherwise, you can soak parts in vinegar or a similar acid to remove hard water deposits. Leave overnight and rinse clean. Hard water deposits form when water dries. If you keep the drip parts shaded and wet continuously, deposits have less chance to form. Mulch can help keep the parts wet.
My Deluxe Punch sometimes fails to cut a clean hole
If you try to cut a hole slowly, the tubing sometimes has time to distort and flatten under the pressure. The secret is to squeeze the handle quickly. Try it on a scrap piece of tubing first. Practice makes perfect. You'll notice that the cutter removes each cut plug of tubing and passes it out the top of the punch - very ingenious and keeps the waste plug out of the tubing.
When should I use sprayers instead of drippers?
irrigation products Use drippers if you can. They are more efficient and don't wet the leaves. But if you need to keep the surface of the soil damp or if you wish to keep the foliage wet, use sprayers. Or if the plants are planted very close in a bed, sometimes a sprayer is easier to add than dripline. Our sprayers are easy to move and they are quiet. It's easy to irrigate odd-shaped beds accurately and the radius of spray can be adjusted. The droplets are smaller than those from a regular high-pressure yard sprinkler and will absorb easily into the soil.
There isn't enough room under the faucet to hang all the drip parts.
irrigation products You can add a length of garden hose to the faucet and then add the drip irrigation parts to the end of the hose, close to where the circuit will start. You could simply lay the assembled drip parts on the ground but usually it's better to make a standpipe to attach the parts and keep them off the ground. We have a tutorial on building a standpipe in the How-To pages.

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